Minnesota has 6 million acres of peatlands, storing 30% of Earth's terrestrial carbon, but drainage for agriculture and forestry has caused significant emissions; restoring peatlands could mitigate over 1 million tonnes/year of carbon

MINNEAPOLIS, Minn. – A new scientific report by The Nature Conservancy in Minnesota (TNC) presents an analysis of Minnesota’s peatlands and a collaborative approach to protecting and restoring peatlands as a method to mitigate the effects of climate change.

Minnesota is home to 6 million acres of peatlands, more than any other state in the contiguous U.S. These unique, waterlogged ecosystems are made up of partially decayed plant materials—effectively trapping carbon underground. Although they cover only 3% of the Earth’s surface, they store around 30% of all the carbon on land.

“Peatlands act like a sponge, both for water and carbon, making them incredible natural climate solutions,” says Maya Swope, climate project manager for TNC in Minnesota. Beyond their carbon benefits, peatlands support plant biodiversity, provide wildlife habitat, offer flood protection and ensure access to fresh water for people and nature.

However, up to one-sixth of Minnesota’s peatlands were ditched and drained for agriculture, forestry and other land uses in the early 20^th century. Even ditches that are no longer actively used to support agriculture or forestry continue to degrade these wetlands by draining water and releasing stored carbon. According to the report, ditched and drained peatlands are causing significant climate impacts.

“Drained peatlands are a major source of carbon emissions, both globally and in Minnesota," says Kristen Blann, freshwater ecologist at TNC. “A recent study by our research partners estimated that previously ditched peatlands alone are contributing about 38,000 metric tons of carbon emissions per year.”

But greater protection and restoration could maximize these landscapes’ ability to reduce emissions and store carbon. The report compiles existing research and new scientific analysis to quantify the potential benefits of restoration. It estimates that restoring and re-wetting farmed and partially-drained peatlands could mitigate more than 1 million metric tons of carbon per year—equivalent to removing 233,000 gasoline-powered cars from the road each year. 

A summary of comprehensive peatlands mapping in the playbook shows that the bulk of partially-drained peatlands identified as candidates for restoration are on public lands, while most of the fully-drained peat areas are privately owned. The approach to peatland restoration must be collaborative and bring the perspectives of all landowners and other interested parties to the table. 

This report is a first step to bring practitioners, agencies and organizations together to work on a shared peatlands conservation strategy in Minnesota and continue to refine the science. It recommends a three-pronged approach to protecting peatlands for the greatest climate and nature benefits:

1. Protect carbon stocks in existing intact peatlands.
2. Re-wet partially drained peatlands to avoid additional carbon loss and restore carbon stocks.
3. Restore fully drained peatlands based on the potential for multiple benefits.

“We hope that a better understanding of peatland ecosystems and their climate benefits will enable organizations, agencies and communities to better manage and restore these special places,” says Swope.

View the full Playbook for Minnesota PeatlandsAuthors and Acknowledgments Authors: Kristen Blann, Christian Lenhart, Mark to peatland protection in Minnesota for centuries, Felice, Maya Swope, Ailene Ettinger, Peter especially at times when white settlers were working Benham hard to ditch and drain these landscapes. Contributors: Megan Wilcots, Anna Kottkamp, The Nature Conservancy is committed to creating Sara Leavitt, Meredith Cornett, Nina Hill a future in which nature and people thrive, and achieving our mission must encompass inclusion, Reviewers: Suzanne Rhees, Anna Rockne collaboration, and supporting Indigenous Peoples. We recognize that as an organization that owns Designers: Lunaris Creative and manages land, the systems and regulations of private property, protection, and lands and waters Graphics: Puntoaparte Editores management that have been core to our work came at a dire cost to Indigenous Peoples. With these Acknowledgements: This guide was developed with words, we acknowledge the traditional stewards, the financial support of The Nature Conservancy’s past, present, and emerging, and recognize our Natural Climate Solutions Prototyping Network, institutional history, responsibility, and commitment. the Bezos Earth Fund, Pew Charitable Trusts, RBC We are committed to gaining deeper awareness of Foundation, Carl Newman and Kelly Larson, and the history and enduring impacts of colonialism— other private donors. including our own contributions to this history as an organization—and resulting responsibilities, including This work would not be possible without the building partnerships based on respect, equity, open impactful work and collaborations from our many dialogue, integrity, and mutual accountability. partners across Minnesota and around the world, including but not limited to: Adapted from TNC’s Voice, Choice, Action Framework: • Pew Charitable Trusts tncvoicechoiceaction.org • Minnesota Department of Natural Resources • Minnesota Board of Water and Soil Resources Cover photo: © Derek Montgomery • Minnesota Pollution Control Agency • Michigan Technological University • United States Forest Service • Friends of Sax-Zim Bog • Ecosystem Investment Partners • SEH Inc. • University of Minnesota We would also like to acknowledge that all of the lands and waters discussed in this Playbook are the homelands of the Ojibwe and Dakota peoples, who are the historic and current stewards of this land. As discussed in the Playbook, tribes have been central TABLE OF CONTENTS Summary 4 Background: Minnesota’s Peatlands 7 Key Takeaways 12 Historic Conversion and Drainage: 13 A Lasting Legacy Legal Protections and Indigenous Conservation Efforts 18 Research-backed Strategies for Restoring and Protecting Peatlands 20 Key Takeaways 21 Quantifying the Benefits and Exploring Opportunities for Peatland Restoration 22 Peatland and Peat Soil Inventory 24 Key Takeaways 30 Estimated peatland soil carbon stocks for Minnesota based on SSURGO 31 Peatland area and carbon stocks by public ownership 33 and administration Estimated extent of drained (fully converted) peatlands 38 Estimated extent of partially drained peatlands 39 Key Takeaways 43 Estimating Carbon Mitigation Potential 44 of Peatland Restoration in Minnesota Emissions avoided from re-wetting and restoring peatlands 45 drained for agriculture Assessing carbon mitigation potential of restoring partially 46 drained peatlands Key Takeaways 52 Scaling Up Implementation 53 Biophysical feasibility 53 Economic feasibility: Costs 60 Economic feasibility: Funding opportunities 62 Sociopolitical feasibility 68 Institutional feasibility 69 Key Takeaways 72 Scaling peat interventions to achieve measurable impacts 74 Healthy peatlands bolster climate change resilience, adaptation, and mitigation 76 Conclusion 77 Funding Acknowledgement 78 Acronyms 78 References 81 PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION Photograph © Derek Montgomery Protecting & Restoring Minnesota’s Peatlands as a Natural Climate Solution Keeping Minnesota’s peatlands healthy is critical for achieving climate goals, but a legacy of drainage has compounded the challenge. Summary al., 2021). Peatland soils represent a huge source of irrecoverable carbon that is at risk Globally and in Minnesota, natural ecosystems of being released due to warming and drying are key to the climate and carbon cycle and play under land use conversion and projected high a critical role in achieving climate mitigation carbon emissions climate change scenarios. goals. This is especially true of peatlands, a type For this reason, both protecting and restoring of carbon-rich wetland ecosystem estimated to peatlands have been identified as potentially store more than 30% of the world’s terrestrial critical Natural Climate Solutions (NCS). These soil carbon while occupying just 3% of the land restoration, conservation, and land management surface. Most of this carbon is stored below activities can increase carbon storage or reduce ground in deep, organic-matter-rich peat soil carbon/greenhouse gas emissions (GHG) from layers. Peatlands begin to release carbon once ecosystems to help mitigate global average they are drained or disturbed. Many peatlands temperature rise. The potential accelerated loss have already been lost or degraded through of carbon from peatlands due to warming is, at drainage for forestry, grazing, agriculture, the same time, one reason why it is so critical to and other forms of land use conversion, and keep global warming as close as possible to 1.5° rising temperatures threaten to flip many C above pre-Industrial averages (Griscom et al., remaining peatlands from carbon sinks to 2017; Roe et al., 2019). sources (Humpenöder et al., 2020; Loisel et Natural Climate Solutions 4 Playbook for Minnesota Peatlands PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION Minnesota contains more peatlands—at least 6 Given the critical role that protecting and million acres—than any other of the contiguous restoring peatlands plays in the global carbon 48 United States. Peatlands cover more than cycle, the Minnesota, North Dakota, and 10% of the state by area and account for at least South Dakota Chapter (Tri-State Chapter) of 37% of the stored terrestrial carbon (Walker, The Nature Conservancy (TNC) is working 2011). Most of Minnesota’s intact peatlands with partners to develop a strategy to protect occur as large open bogs, extensive lowland and restore peatlands in Minnesota as an conifer forested peatlands, and groundwater- important component of an overall climate fed fens. Historical drainage and conversion of change mitigation strategy. This Peatland peatlands to cropland and other land uses has Playbook describes those science-based caused persistent shifts in the carbon balance of Minnesota’s peatlands. Ongoing carbon efforts to estimate the potential climate stock losses from partially drained peatlands in benefits of peatland protection and restoration Minnesota—a legacy of extensive ditching and in Minnesota, identify promising targets drainage efforts in the early 20th century—have for restoration, and propose strategies for been estimated at ~38,000 metric tons (MT) continuing these efforts. per year (Krause et al., 2021); however, some estimates in the literature suggest that re-wetting peat could potentially save even more than that per year. Re-wetting drained peatlands may also provide additional carbon sequestration benefits. Minnesota Figure 1. Minnesota peatlands in context of global and North American peatlands extent. (Data from Hugelius et al. 2020; inset from Global Peatlands Assessment, UNEP 2022) Natural Climate Solutions 5 Playbook for Minnesota Peatlands PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION Figure 2. Peat landforms and ecological land type associations in relation to extent of glacial lake basins (map compiled from MN ECS land type association data layer and Quaternary Geology lobes from Minnesota Geological Survey (MGS, Lusardi, 1994). Natural Climate Solutions 6 Playbook for Minnesota Peatlands PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION Photo: TNC Background: Minnesota’s They predominantly developed during the Holocene epoch (the past 6,000–8,000 years), when favorable peatlands peat-forming conditions persisted due to cool, wet climate periods combined with poor drainage in the Peat is partially decayed plant material that depressions left behind by Ice Age glaciers. accumulates in soil under moist and often cool climates, where waterlogged conditions prevent In Minnesota, most of our peatlands formed microbes from breaking down dead plant material either by lake in-filling or by “paludification.” In the and leaves. In the process, the carbon dioxide first case, peatlands formed as lakes and ponds (CO2) that plants remove from the atmosphere left behind by the retreating glaciers, and which becomes sequestered underground so long as gradually filled in around the edges with floating waterlogged conditions are maintained. While mats of sedges and other plants while organic all peatlands are wetlands, not all wetlands are matter accumulated at their bottoms. In the second peatlands. A peatland is typically defined as process, flat or gently sloping ground developed a wetland that accumulates peat, or partially into raised bogs formed by mosses and sedges decayed plant matter. Peatlands are also generally that accumulated organic matter faster than the referred to as fens, bogs, and swamps, though rate of decomposition, cutting them off from local peatland definitions can vary widely (Lourenco et groundwater. The most extensive peatlands in al., 2022).(see Box 1). Minnesota formed in the remnant glacial lake basin Upham in Aitkin and St. Louis counties (including Minnesota’s true peatlands are largely an extension the Sax-Zim Bog as well as Toivola Bog and of a band of northern temperate peatlands stretching Wawina Peatlands) and Glacial Lake Agassiz (Red across Canada into the Great Lakes region (Figure 1). Lake, northern Minnesota and Ontario Peatlands). Natural Climate Solutions 7 Playbook for Minnesota Peatlands PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION Box 1. Peat and Peatland Types Bog vs fen vs swamp Bogs receive their moisture from rainwater and runoff low in dissolved minerals. Only a small number of specialized plant species can survive these acidic and nutrient-poor conditions. Bogs have undulating terrain covered by Sphagnum moss as well as low shrubs, cottongrass, and sparse stunted spruces and tamarack. Bogs tend to have a surface layer of minimally decomposed fibric peat. Fens are influenced by groundwater with near-neutral to basic pH and carrying dissolved minerals supporting higher plant diversity than bogs. Calcareous fens are a rare and distinctive type of fen; they depend on a constant supply of upwelling groundwater rich in calcium and other minerals and support diverse and unique rare plants. Fen plant communities are dominated by low shrubs and fine- leaved sedges, with brown mossses and Sphagnum mosses common. Peat in fens tends to be more highly decomposed (hemicsapric) than in bogs. Swamps are forested wetlands often adjacent to lakes or streams. They may be fed by surface or groundwater but are saturated or flooded for many weeks or months each year. Not all swamps are peatlands: Minnesota’s lowland conifer swamps, dominated by black spruce and/or tamarack, may be bogs or fens, but white cedar, black ash, shrub swamps, and bottomland hardwoods typically have lower soil carbon and therefore less often meet the definition for peat soils. Peat vs Histosol Peat is a general term for soils formed from partially decayed plant matter and can include the barely decomposed fabric Sphagnum peat common in northern bogs to the highly decomposed capric sedge/reed mucks of wet meadows. Histosol is an older term in the USDA’s soil taxonomy classification system, and is characterized by a thick layer of organic soil. Histosols must have a layer of organic soil material at least 40-60 cm deep. In many cases, peat and histosols are synonymous, and histosols, which are extensively mapped in the United States, can be used as a proxy for peatlands. Sphagnum vs sedge peat Sphagnum peat is formed from partially decomposed Sphagnum moss, which is resistant to decomposition and abundant in nutrient-poor acidic bogs. It tends to be less decomposed (fibric), with very low bulk density and high hydraulic conductivity. Reed/sedge peat is formed from partially decomposed reeds, sedges, grasses, and other herbaceous vascular plants, which are less resistant to decomposition than Sphagnum and abundant in more mineral-rich, neutral pH environments, resulting in higher rates of decomposition. Reed/sedge peat is often more decomposed (hemic or sapric), with higher bulk density and lower hydraulic conductivity. Natural Climate Solutions 8 Playbook for Minnesota Peatlands PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION BOX 2. Peatland Systems according to the Minnesota Native Plant Community classification The Minnesota Department of Natural Resources’ Native Plant Community Classification system recognizes 3 peatland types at the system level: acid peatlands, open rich peatlands, and forested rich peatlands. Broadly speaking, acid peatlands include the more nutrient-poor bogs and fens, which are also called “ombrotrophic” in reference to the fact that they receive their moisture and nutrients primarily from precipitation or runoff, and which are largely disconnected from local groundwater. These highly acidic and nutrient-poor conditions are only suitable for a small number of specialized plants, but those that have adapted to these harsh conditions tend to be widely distributed globally across the boreal peatlands. Ground cover is dominated by hummocks and hollows of Sphagnum moss with cottongrass and low ericaceous shrubs, such as bog laurel, bog rosemary, leatherleaf, and labrador tea. Acid peatlands may be completely open or forested with sparse stands of stunted spruce and tamarack trees. Carnivorous plants, such as pitcher plant and sundew are common and have adapted to the nutrient-poor conditions by trapping and digesting insects. Due to the acidic conditions and recalcitrant litter from sphagnum, the soils in these systems tend to be minimally decomposed fibric peat. Natural Climate Solutions 9 Playbook for Minnesota Peatlands PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION BOX 2. Continued hummocks and brown mosses in hollows. High water tables prevent tree growth, leaving these Open rich peatlands have some influence systems open. from groundwater, which provides a source of minerals, but are still generally low in nitrogen Open rich peatlands may eventually transition and phosphorus. These systems host higher to acid peatlands as peat accumulation plant diversity, dominated by low shrubs, such leads to separation from groundwater and as leatherleaf, bog rosemary, and bog birch, Sphagnum mosses increase the system’s and fine-leaved sedge. Hummock-hollow acidity. Moderately decomposed hemic soils topography is common, with Sphagnum on are common in these systems. Similar to open rich peatlands, forested rich peatlands also receive groundwater inputs, allowing for greater plant diversity than acid peatlands. However, fluctuating water tables allow for denser canopies of coniferous trees, favoring shade-tolerant understory species with extensive cover of feathermosses and brown mosses, as well as abundant shrub and forb cover. The soils of these forested rich peatlands are often also hemic or even more decomposed sapric peats. Natural Climate Solutions 10 Playbook for Minnesota Peatlands PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION BOX 2. Continued Highly disturbed, degraded, or recently rewetted peatlands may also feature vegetation more typical of wet meadow/carr wetland type. For more information about Minnesota’s peatlands, see:  Minnesota’s Peatland Scientific & Natural Areas dnr.state.mn.us/snas/peatlands.html   Restoring Minnesota’s Peatlands for Climate & Water nature.org/en-us/about-us/where-we-work/united-states/minnesota/stories-in-minnesota/ peatland-restoration-study/  Peatland Restoration in northern Minnesota ncsprototypingnetwork.naturebase.org/en/projects/united-states-peatlands  Natural Climate Solutions 11 Playbook for Minnesota Peatlands PROTECTING & RESTORING MINNESOTA’S PEATLANDS AS A NATURAL CLIMATE SOLUTION Key Takeaways • Peatlands are wetlands characterized by the long-term accumulation of partially decayed plant material known as peat, which sequesters carbon underground due to waterlogged conditions. • Minnesota’s peatlands are part of a northern temperate peatland band formed in the Holocene era around 6,000–10,000 years ago because of melting glaciers and a cool, wet climate paired with poor drainage. • The formation of Minnesota’s peatlands is mainly attributed to lake in-filling, where shallow ponds and lakes gradually filled in with organic matter, or where flat grounds developed into raised bogs formed by mosses and sedges accumulating peat faster than the rate of decomposition. Natural Climate Solutions 12 Playbook for Minnesota Peatlands HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY Photograph © Derek Montgomery Historic conversion and drainage: a lasting legacy Until the late 19th century, the place now known everyone supported these large-scale drainage as Minnesota was a landscape dominated efforts, as much as 90% of historic wetlands in by wetlands of various types including bogs, southern and western Minnesota were drained. fens, marshes, swamps, and wet prairies. These efforts enabled the intensive row crop The Indigenous people who stewarded agricultural production systems that dominate these landscapes valued the peatlands as those parts of the state today. intact ecosystems that furnished them with food, medicines, furs, and other necessities. Based on the updated 2018 Statewide Altered However, when European settlers moved Watercourse mapping project, more than 41,000 into the landscape, they viewed these poorly miles of streams in Minnesota have been altered drained areas as wastelands, and made massive or modified in some way—representing nearly half drainage investments to make land available for the total, and nearly double previous estimates. “productive” agriculture and forestry uses. In Of this, at least 7,000 miles cross areas with support of this project, the federal government peatlands. Restoring peat in these areas, therefore, passed a series of Swamp Acts starting in the has the potential to generate both climate benefits 19th century to encourage draining wetlands and restore more natural waterways. throughout the Great Lakes States (Dahl and Allord, 1996). Peatland areas that have been completely drained and converted represent a significant loss of State and local governments in Minnesota took up stored carbon, in addition to ongoing losses. In the charge in earnest throughout the early 1900s, 2018, the Minnesota Pollution Control Agency dredging long trenches and using explosives to (MPCA) listed cultivated histosols—thick, drain millions of acres of wetlands. While not organic-rich soils indicative of potential peat Natural Climate Solutions 13 Playbook for Minnesota Peatlands HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY Carbon Cycle In Intact vs. Drained Peatlands Figure 3. By definition, intact peatlands are net sinks for carbon; this is true in the long run even when accounting for the higher short-term radiative forcing of CH4. By lowering the water table, drainage exposes Carbon stored in the peat. This ultimately leads to increased CO2 emissions while having variable impacts on CH4 production, with slow-moving ditches even serving as hot spots for methane release at times. soil forms—as the fourth largest source of GHG Even in these partially drained northern emissions statewide, just behind light trucks peatlands, the legacy of ditching still (MPCA 2023.) Historically, the state’s largest contributes to ongoing carbon stock losses areas of complete peatland loss and conversion and peat degradation. were in central, southern, and western Minnesota. Despite being partially or fully drained, many of Peatland ecology is largely governed by these areas still have peat soil characteristics, hydrology—the patterns governing water quality, often in conjunction with landscape position and water chemistry, water flow, and water table topographic modeling indicative of wetlands dynamics. Disrupting these dynamics has had (Natural Resources Research Institute, 2019). profound impacts on the accumulation of peat, landforms, vegetation, and carbon. Ditches dug In contrast, large peatlands— both intact and through peatlands lower the water table, leading partially-drained— persist in northeastern to oxidation (decomposition) of organic matter Minnesota and north of Upper and Lower Red and the release of CO2 and other greenhouse Lakes. In these more extensive northern peatland gases (Krause et al., 2021), as shown in Figure 3. areas, many drainage efforts were economically Although many ditches have not been maintained unsuccessful, and millions of acres reverted to in decades, they are often still part of active public state and county administration via tax forfeit, ditch networks upstream and downstream and beginning largely during the Great Depression. continue to provide a preferential flow path for Today these lands are managed primarily as surface waters through the peatlands. Without county and state lands. active intervention, many of these systems may Natural Climate Solutions 14 Playbook for Minnesota Peatlands HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY Lateral Drainage Effect in Peatlands Figure 4. Lateral drainage effect in a northern Minnesota ditch. The light grey outline shows the approximate soil and water surface prior to drainage ditch construction in the early 1900s. The water table line in the left foreground shows the predicted lateral effect from the drainage ditch. Restoration of Minnesota’s partially drained peatlands through ditch filling and re-wetting therefore potentially involves both peatland NCS pathways: peatland protection (avoided conversion by stopping ongoing stock loss) and peatland restoration (carbon storage and sequestration by reversing and re-starting the accumulation of peat based on re-wetting of the peat and restoring the water table elevation). not recover hydrologically for many more decades, potential drainage impact of a ditch, where not though some may be capable of healing on their all the peat and muck has yet been fully oxidized own, given adequate time. and mobilized to the atmosphere, releasing greenhouse gases. These lateral effects can Recent mapping and modeling show about extend 100 meters or more to either side of the one-sixth of total peatlands in northern ditch depending on slope, ditch depth, soil type, Minnesota may be experiencing ongoing carbon and other properties (MN BWSR, 2013). Recent stock losses as legacy impacts from ditching, estimates in Minnesota indicate that this water contributing an estimated 38,000 metric tons table impact also causes ongoing carbon losses (MT) of carbon emissions per year. that extend laterally about 100-150 meters from the ditch, with decreasing impacts further from The original intent and purpose of drainage the ditch (Krause et al., 2021; Reagan, 2023). ditches was to lower the water table in saturated or wet areas of the landscape by providing In general, re-wetting drained peatlands greatly channelized outlets. Drainage ditches impact reduces loss of carbon as CO2 via decomposition wetland hydrology by drawing down the adjacent by restoring anaerobic, saturated conditions water table, with lateral effects extending favorable to peatland vegetation and long-term out perpendicularly. Figure 4 shows a cross- peat accumulation (Wille et al., 2023). However, sectional conceptual diagram of the remaining wetter conditions may increase methane (CH4) Natural Climate Solutions 15 Playbook for Minnesota Peatlands HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY production in the short term. (approximately 28x dissolved organic carbon (DOC). the DOC carried the global warming potential (GWP) of CO2 over in ditches results in significant overestimation 100s). However, CH4 has a short atmospheric of the carbon sink strength of many wetlands lifetime, and emissions do not have a cumulative (Dinsmore et al., 2010; Leach et al., 2016). impact on warming like CO2. The overall weight DOC also plays a role in the mobilization and of evidence in the literature on re-wetting bioaccumulation of methylmercury in fish and peatlands strongly suggests the longer-term CO2 other animal tissue, a major water quality issue emission reduction benefits and reestablished in many Minnesota watersheds. By restoring organic matter accumulation far outweigh the peatlands, closing ditches, and increasing climate impacts of increased CH4 emissions. residence time, there is potential to reduce Thus, the long-term net carbon benefits of DOC export downstream and potentially restoring drained peatlands via re-wetting are methylmercury export as well (Kolka et al., 2011; substantial and increase the sooner peatlands Waddington et al., 2008). However, although are restored (Figure 5). current research is examining the effects of restoration on DOC and mercury transport in Drainage ditches also export large quantities of Minnesota, the processes involved are complex carbon to downstream ecosystems in the form of and we need a better understanding of them. Natural Climate Solutions 16 Playbook for Minnesota Peatlands HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY Figure 5. Restoring the sink: implications of short-term tradeoffs between CH4 and CO2. Radiative forcing (RF) is the difference between the solar energy coming into the Earth’s atmosphere and the amount reflected back to space; it is a key measure of the greenhouse effect. The graphs show radiative forcing and global climatic warming effects of global peatland management without (left) and with (right) an initial 10-times-larger-CH4-peak for 5 years after re-wetting, under various scenarios. Drain_ More: Assumes that the area of drained peatland continues to increase from 2020 to 2100 at the same rate as between 1990 and 2017; No_ Change: The area of drained peatland remains at the 2018 level; Re-wet_All_Now: All drained peatlands are re- wetted in the period 2020–2040; Re-wet_Half_Now: Half of all drained peatlands are re-wetted in the period 2020–2040; Re- wet_All_Later: All drained peatlands are re-wetted in the period 2050–2070 (Günther et al. (2020). Nature Communications 11:1644; Figure reprinted from Figure 2 of RAMSAR Policy Brief) Natural Climate Solutions 17 Playbook for Minnesota Peatlands HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY Photograph © Derek Montgomery or a wetland mitigation bank. However, there Legal protections are numerous de minimus exemptions under and Indigenous the WCA that allow some excavation of minimal size and depth without a wetland permit for uses conservation efforts such as horticultural peat, as well as a silvicultural exemption (relevant to drainage on state and After earlier eras promoting drainage, public private forested peatlands). Additionally, although perception of the importance of wetlands and mitigation wetlands are supposed to replace the peatlands began to shift in the late 1980s, partly in same types of wetlands and wetland services in response to growing efforts from conservationists, the same watersheds, this is not always possible scientists, Tribal Nations, and others to articulate in practice. While WCA acknowledges that the value of protecting them in their natural carbon sequestration is a service that wetlands state. The Minnesota Wetlands Conservation provide, mitigation requirements do not explicitly Act (WCA), passed in 1991, established a goal of require carbon accounting or monitoring at this “no net loss” of wetland functions and services, time. Furthermore, regardless of the quality of the and multiple peatland areas were designated restoration, there is still a lag time in the recovery in the 1990s under the Scientific and Natural of wetland hydrology, vegetation/biodiversity, Areas Program administered by the Minnesota restoration of carbon dynamics, and other Department of Natural Resources (DNR). Since benefits. In part to account for these drawbacks, these changes came into effect, Minnesota has credits for replacement wetlands are typically maintained relatively strong legal protections offered at mitigation ratios ranging from 2:1 to 8:1, for peatlands. Wetlands in general are subject an aspect of mitigation law that does provides to the WCA and several other regulatory some opportunity to increase peatland acreage programs, most of which are implemented and beyond “no net loss.” coordinated at the local level but overseen and administered by the Board of Water and Soil Tribal Nations and Indigenous communities in Resources (BWSR). Drainage or impacts due to Minnesota have also contributed significantly infrastructure, development, mining, or other to peatland conservation and stewardship. In purposes generally require a wetland permit that particular, the Red Lake Nation actively opposed requires mitigation through wetland restoration county, state, and federal efforts to drain and Natural Climate Solutions 18 Playbook for Minnesota Peatlands HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY develop northern Minnesota peatlands for decades, both on- and off-reservation, recognizing their intrinsic values as well as their provision of habitat for wildlife and cultural resources such as medicinal plants, contributions to water quality and storage, and the other services they provided (Meyer, 1992). This culminated in the 1970s with a resolution by Red Lake tribal leaders to preserve the peatlands untouched in response to a large proposed peat mine energy development in the peatlands north of Red Lake Nation that was, fortunately, ultimately abandoned. To this day, some of the larger areas of undrained, intact peatlands in Minnesota occur within the Red Lake reservation boundaries, as part of the larger expanse of the Red Lake peatlands. Other Tribal Nations with significant peatland areas on-reservation include Fond du Lac, White Earth, Bois Forte, Mille Lacs, and the Leech Lake Band of Ojibwe. However, in many cases, treaty resources such as wild rice lakes, wetlands, and flowages have been and continue to be impacted by drainage activities on adjacent public and private lands. for Minnesota science and policy is to keep pace On state- and county-owned land, peatlands with emerging threats and challenges to ensure are managed according to their designation as we continue to manage our peatlands in ways public wildlife management areas, forestry lands, that benefit people, water, wildlife, biodiversity, conservation or recreation areas, as well as based and climate. on mining regulations and other obligations under statute. These varied interests are not always in accordance with peatland conservation and restoration. There is growing demand for Research-backed strategies copper, nickel, and rare earth materials driven for restoring and protecting by expanded production of electric vehicles and other products deemed necessary for the clean peatlands energy transition, and many mining companies are eyeing northern Minnesota’s mineral resources. For several years, The Nature Conservancy in Several new mining projects in this region are Minnesota has identified wetland and floodplain proposed or in the pipeline. Although the acreage restoration as a major element of our overall of remaining peatlands at risk of complete freshwater strategy under our Resilient Waters drainage or conversion is relatively limited, these program. To that end, we have been implementing peat areas play an outsize role in terms of at- wetland restoration projects for multiple benefits risk carbon stocks, potential implications for in central Minnesota since 2017 or earlier, water quantity and quality, connected and intact including many peatlands. However, this report wildlife habitat, and biodiversity. The challenge details our initial efforts to identify peatland-specific Natural Climate Solutions 19 Playbook for Minnesota Peatlands Photograph © Mark Godfrey HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY restoration opportunities and to characterize the biophysical, social, institutional, and economic In order to achieve our carbon feasibility of peatland protection, management, and mitigation and sequestration goals and restoration across the overall landscape. align with stakeholder needs, we consider the following peatland protection The focus of our analysis in this document is and restoration strategies. They take largely expanding this strategy to prioritize into account cost, carbon mitigation restoration of partially-drained peatlands in effectiveness, and geographic extent of northern Minnesota, particularly on public the need and opportunity: lands, as part of our climate mitigation strategy. Expanding our ability to assess carbon benefits 1. Protect intact peatlands from of restoring drained organic-soil wetlands in southern Minnesota provides additional ability to further degradation as well as direct prioritize, target, and assess benefits of floodplain conversion threats such as agriculture, and wetland restoration. mining, and development. Although the focus of this document is on 2. Restore and re-wet partially restoration opportunities and feasibility, we drained peatlands. emphasize that protection—i.e., avoiding irreversible carbon loss from additional 3. Completely restore fully drained and conversion, drainage, or other avoidable impacts converted peatlands. to peatlands, wherever possible—is the most critical priority for peatlands in Minnesota and globally, due to their large carbon stores that have accumulated over millennia. Photograph © Derek Montgomery Natural Climate Solutions 20 Playbook for Minnesota Peatlands HISTORIC CONVERSION AND DRAINAGE: A LASTING LEGACY Key Takeaways Historical Wetland Loss and Drainage Efforts: • In the late 19th century and early 20th century, federal, state, and local governments undertook efforts to drain wetlands, impacting millions of acres of wetlands and peatlands in Minnesota. Carbon Loss and Restoration Challenges: • Draining peatlands contributes significantly to greenhouse gas emissions. Even partially drained peatlands experience ongoing carbon stock losses due to historic ditching, contributing an estimated 38,000 MT of carbon emissions to the atmosphere annually. • Re-wetting drained peatlands is crucial for long-term carbon benefits, despite short-term CH4 emissions, and can also reduce downstream carbon export. Legal Protections and Indigenous Conservation Efforts: • The Minnesota Wetlands Conservation Act in 1991 inaugurated relatively strong legal protections for peatlands in the state. In addition, Tribal Nations including Red Lake Nation have actively opposed drainage efforts, recognizing peatlands’ intrinsic values, cultural resources, and importance for wildlife and biodiversity. • Additional forms of protection, including designation of peatland SNAs and calcareous fen protections in statute, have been added more recently. • However, challenges persist such as exemptions for horticultural peat and ongoing threats from agriculture, forestry, mining, and climate change. Peatland Strategy: • The Nature Conservancy proposes a three-pronged peatland strategy: protect large standing carbon stocks, re-wet partially drained peatlands in the north, and restore fully drained peat wetlands for multiple benefits. • This document will focus on opportunities and strategies for peatland restoration on partially drained peatlands. Natural Climate Solutions 21 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION Photograph © Derek Montgomery Quantifying the benefits of and exploring opportunities for peatland restoration We began our science-based approach for We then combined peatland extent with quantifying the potential climate mitigation empirical estimates of avoided carbon stock benefits of peatland protection and restoration loss and carbon sequestration rates associated pathways by identifying the current and historical with different peatland protection and extent of peatlands in Minnesota. restoration strategies. We worked to assess existing carbon stocks, determined where peatlands have been most affected by drainage ditches and other hydrologic alterations, and compiled estimates of long- term carbon accumulation rates and shorter- term emissions factors associated with different peatland types and conditions. We also derived maps of historical peatland extent by compiling publicly available data layers for soil properties, existing wetland inventories, historical vegetation, and existing native plant communities. Natural Climate Solutions 22 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION Figure 6. Minnesota peatland extent as represented by overlay of NWI simplified plant community types (MNDNR, 2019) with mapped histosols (USFS 2024). Natural Climate Solutions 23 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION Peatland and peat soil extent of remaining intact and partially-drained peatlands as well as fully drained and converted inventory peat soils. Globally and in Minnesota there is considerable variation in how peatlands can be defined and To view these data layers online, see the mapped, depending on the availability and quality of data, the scientific discipline involved, and Potentially Restorable Peatlands Mapping whether the primary interest is in vegetation, Tool developed by BWSR concurrently soil, or economic properties of the peat, etc. Contradictions in definitions often relate to the with the development of this Playbook minimum depth or percent of organic matter http://bit.ly/4hyum8Q required for a soil to be considered as peat, and whether carbon content is based on mass or volume (Lourenco et al., 2022). Minnesota actually has an abundance of available Peat soils are classified as histosols, based data on soils, vegetative communities, and primarily on depth and organic carbon content existing peatland inventory work done by our (Kolka et al., 2016). To estimate carbon and peat state natural resource agency, the DNR, and volume loss from ditched peatlands in Minnesota, others. This includes a statewide Peat Inventory Krause and 16 colleagues (2020; 2021) developed Project conducted from 1976-1982 to assess the a peatland layer for Minnesota based on the energy and horticultural potential for the state’s updated Minnesota National Wetland Inventory peat resources as well as inform a comprehensive (NWI), a Minnesota-specific update to the policy on peatland management. NWI, completed by the Minnesota DNR in 2019 (MNDNR, 2019) The NWI was intersected with Early peat inventories actually estimated the histosols as mapped at the level of taxonomic statewide extent of peat at over 7 million acres; order by the National Resources Conservation larger than recently cited figures of 5-6 million Service’s (NRCS) digital Soil Survey Geographic (Minnesota Soper 1919; MNDNR 1981a, Glaser (SSURGO) database (USFS 2024). Krause 1987). These datasets vary in their accuracy et al. (2021) limited their analysis to areas of and spatial resolution, as well as how complete equal to or greater than 85% histosol content they are statewide. Although peatlands can be that intersected NWI wetlands, irrespective of identified, mapped, and/or classified by a variety whether peat was indicated in the NWI wetland of attributes (soil types, plant communities, classification. However, this approach resulted hydrogeomorphic wetland categories, etc.), a in the inclusion of only 86% of the area of all single complete statewide coverage of drained wetland features classified as peatlands based on and remaining peatlands did not exist prior to this hydrogeomorphic class in the updated NWI. project, although efforts have recently begun to update the state’s peat maps and data layers. Building on the Krause et al. (2021) approach to ensure the broadest possible inclusion of To assess both intact and potentially drainage- potential peat, we compiled a comprehensive set impacted peat wetlands in Minnesota, we used of statewide layers of peat soils and wetland types multiple geospatial data layers to assess the in Minnesota by cross-walking the statewide Natural Climate Solutions 24 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION Figure 7. Statewide acres by percent histosol content. (Total 7.8 million acres) SSURGO soils data1—expanded to include soils having 10% or more histosol content in soils. The with 10% or more histosol content, as well as other vast majority of these areas are characterized relevant SSURGO variables relating to peatland as in natural, native, or perennial land cover, in types including carbon content, nutrient status, spite of the extensive artificial drainage networks texture, and chemistry—with the NWI, the 2019 that remain. 6.7 million acres intersect with the National Land Cover Dataset (NLCD), and several updated NWI (Table 1, Figure 8). An additional other vegetation models developed to characterize 490,000 acres of these histosols are not mapped native wetland plant communities and potential. in the NWI, but classified as woody or emergent wetlands in the 2019 NLCD. Excluding lakes Based on this newly compiled SSURGO histosol and open water, about 60% of the total NWI layer, 7.8 million acres statewide are mapped as wetland acreage has soils classified as histosols 1Histosols are defined by the NRCS as “soils that are dominantly organic … commonly called bogs, moors, or peats and mucks. A soil is classified as a Histosol if it does not have permafrost and is dominated by organic soil materials.” SSURGO categorizes “histosols” as one of the soil taxonomic orders using the “taxorder” variable in the component attribute table. This layer is derived from a nationwide analysis compiled by the USFS based on the USDA-NRCS gSSURGO (gridded Soil Survey Geographic) database, in which the “component” additional table was joined and queried by a custom Python script, and from taxorder and taxclname (Seq 83 and 84 in the table found here) a dataset was derived showing histosols in 10% brackets based on the percentage of histosols within the components for the map unit. Analysis was conducted on all soils with 10% or more histosols. Natural Climate Solutions 25 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION (Table 1). Wetland types most likely to be More than half the state’s northern peatlands are mapped as peatlands are conifer bogs and open in state or county ownership. Since the era when bogs. Wetland types less likely to be mapped as most northern peatlands reverted to state or county histosols are deep marsh, shallow open water, and ownership, the main economic use of peatlands by non-vegetated aquatic communities. While these area has been for forestry, though mineral leases wetland types do often occur on mineral soils (including peat mined for horticulture as well rather than peat, this could also indicate some as other mineral resources) provide the bulk of potential mismatch or error in mapping. revenue (see discussion in next session). Figure 8. Crosswalk of NWI simplified Plant Community Class (SPCC) with histosols. Natural Climate Solutions 26 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION Photograph © Derek Montgomery Table 1. Crosswalk of soils containing 10% or more histosols with the simplified plant community class from Minnesota updated National Wetland Inventory. Natural Climate Solutions 27 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION Box 3. Sources of Geospatial Data on Peatlands Minnesota’s peatlands range from the lowland conifer forests, swamps, bogs, and patterned peatlands of northern and northeastern Minnesota to smaller bogs and fens in the south and west. However, at the outset of this project, there was no comprehensive statewide data layer characterizing vegetation, hydrology, and soil characteristics for all of Minnesota’s “peat lands.” We used the following data layers and sources to describe peatland extent and characteristics: The Soil Survey Geographic (SSURGO) Database generally has the most detailed level of soil geographic data developed by the National Cooperative Soil Survey (NCSS) in accordance with NCSS mapping standards. The tabular data represent the soil attributes and are derived from properties and characteristics stored in the National Soil Information System (NASIS). Histosols are identified as a taxonomic order using the “taxorder” variable in the component attribute table. Other variables in SSURGO tabular datasets can be used to characterize soil organic content, taxonomic reaction class (an indicator of pH), texture, etc. Minnesota Wetland Inventory (Kloiber et al. 2019). The Minnesota Wetland Inventory is a publicly available GIS database based on the original National Wetlands Inventory (NWI) as completed for Minnesota by USFWS and updated by MNDNR, Ducks Unlimited, and St. Mary’s University from 2008-2013. In addition to the principal wetland classification scheme adopted for the NWI (Cowardin et al. 1979), the MWI classifies wetlands using the Circular 39 wetland type system often referenced in Minnesota wetland statutes (Shaw and Fredine 1956) as well as a simplified hydrogeomorphic (HGM) classification based on landscape position, landform, waterbody type, and water flow path, adapted from a system developed by Brinson (1993) for the U.S. Army Corps of Engineers and adapted by Tiner (2014) for inclusion in remote-sensing-based wetland inventories. Although none of these classification systems explicitly and consistently distinguishes between peatland versus mineral wetlands, crosswalking them against the histosol soil layer provides a relatively complete picture of peatland hydrologic and vegetation types. MNDNR Native Plant Communities is a database published on Minnesota’s Geospatial Commons based on field survey data collected by MNDNR Division of Ecological and Water Resources through the Minnesota Biological Survey (MBS). It is conducted by county, extracted and attributed through a rigorous internal process based in part on the Minnesota Ecological Classification System developed for native plant community complexes used by the EWR. Data are complete only for state parks and counties that have completed surveys, and partially complete for state forests and WMAs. Potential Native Plant Communities of northern Minnesota: a geospatial model of potential peatland systems developed at the University of MN-Duluth’s Natural Resources Research Institute (NRRI) as part of an effort to map potential Native Plant Communities (NPCs) across the major forested ecological subsections of northeastern and north-central Minnesota (Brown et al. 2013). The peatland layer developed by NRRI includes three different peatland system types Natural Climate Solutions 28 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION Box 3. Continued (i.e., Acid Peatlands, Forested Peatlands, and Open Peatlands) mapped across the three ecological sections that make up the Laurentian forests of Northeastern and north-central Minnesota. Other datasets used to characterize existing and potential vegetation and land cover included the Cropland Data Layer (NLCD). Additional datasets we considered but ultimately did not make significant use of included the MNDOT Historic Vegetation Potential model and the Marschner map of pre- settlement vegetation. Additional analysis including these and more recently obtained datasets is included in an Appendix. (Brinson and others, 1993; Brown et al., 2014; Cowardin, 1979; Kloiber et al., 2019; Shaw and Fredine, 1956; Tiner, 2014) Photograph © Derek Montgomery Natural Climate Solutions 29 Playbook for Minnesota Peatlands QUANTIFYING THE BENEFITS OF AND EXPLORING OPPORTUNITIES FOR PEATLAND RESTORATION Key Takeaways • We mapped peat soils based on 10% or more histosol components in order to estimate re-wetting opportunity on both drained and partially drained lands (see later section in document). • 7.8 million acres of land in Minnesota has 10% or more histosol content. 6.7 million acres of this is accounted for as wetland area in the state. Natural Climate Solutions 30 Playbook for Minnesota Peatlands Photograph © Derek Montgomery ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Photograph © Derek Montgomery Estimated peatland soil carbon stocks for Minnesota based on SSURGO Minnesota peatlands are sometimes referred USDA-NRCS STATSGO and NASIS database, and to as “boreal peatlands” (included as part of the 1990 LMIC land cover data. Carbon stock the southern extent of North American boreal estimates from that analysis were generally peatlands), or as part of a band of “temperate” accurate for northern Minnesota counties, as the (non-permafrost) peatlands extending into 1980s Minnesota DNR peatland inventory was Minnesota from Canada. Peat deposits of this based on extensive soil sampling and soil cores region, including northern Minnesota, tend that included information on peat depth, profiles, to be deeper than those of the subarctic, with botanical origin, and Von Post decomposition. The higher long-term net carbon accumulation rates 5.7-million-acre area estimate, however, did not (Bridgham et al., 2006; Gorham, 1991; Grigal et include many of the organic-soil wetlands in the al., 2011; Kolka et al., 2016; Ovenden, 1990). central and southern part of the state classified as wet meadows, shrub swamps, or forested Assessing the overall potential for terrestrial swamps, many of which have peat or muck soils. carbon sequestration in Minnesota, Anderson and colleagues (2008) estimated that 5.7 For the purposes of summarizing peatland carbon million acres of peatland in the state contain stocks spatially, we created a statewide raster 4,250 million metric tons (MMT) of carbon, or map of soil organic carbon (SOC) in the top 100 approximately 745 metric tons of stored carbon cm of soils as derived from the NRCS digital soil per acre. This estimate used data from the database SSURGO (SOC0_100). 1980s Minnesota DNR peatland inventory, the Natural Climate Solutions 31 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO The amount of carbon stored in soils— We also note that in the decades since SSURGO and STATSGO data was originally mapped and particularly in the top layer most digitized, there likely has been additional loss of likely to be exposed or impacted by peat from oxidation and decomposition. conversion, erosion, drainage, drought, or other water table impacts—also represents the amount of carbon that can be lost to the atmosphere as CO2, if wetland systems are degraded through drainage or natural disturbances such as peatland fires. Summing that layer statewide, we estimated total carbon in the top one meter at 4.49 Petagrams (Pg), or 4.49 billion metric tons. Soil organic carbon in the soil layer mapped as 10% or more histosol component totaled 1.99 Pg, representing 44% of total soil carbon in the top one meter while making up just 15% of the state by area. Repeating this analysis for estimated SOC at 100- 150 cm and 150-999 cm and summing the results from all three depth profiles, histosols account for 3.1 of a total of 6.1 Pg of carbon statewide, or more than half of all soil organic carbon. This estimate is smaller than the 4.25 Pg estimate reported by Anderson et al (2008), and is likely an underestimate, as SSURGO estimates and accuracy vary by county and are increasingly incomplete or inaccurate at greater depths. Furthermore, our compiled digital soil maps are incomplete for three of the highest peatland- containing counties: Cook, Lake, and Pine (although very recent updates to SSURGO have filled in some of these gaps, these updates were not available at the time of this analysis). Natural Climate Solutions 32 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Peatland area and carbon stocks by public ownership and administration Of the approximate 51 million acres of total land (not including more than 3 million acres of open water) within the borders of Minnesota, approximately 12.5 million acres (around 25%) are currently owned and/or administered by federal, state, or county authorities. Another 0.7 million acres are tribally owned.2 Of the 7.8 million acres of land identified as having peat soils (10% or more histosol content), roughly 4.5 million (~60%) are in public ownership. The majority of these peatland areas are state- owned, particularly in northern Minnesota. Historically, wetlands, including peatlands, were more likely to stay in or revert to state ownership. In general, the peat soils that are in private ownership occur in smaller, less extensive patches (and often include lower percent histosols), whereas the larger peat landscapes are much more likely to be in public ownership. They are managed under a variety of different state administrative and surface interest categories, depending on how they were acquired and for what purposes they have most recently been designated, which has important implications for strategy and opportunities for carbon management, as described later in this section. Photograph © Derek Montgomery Natural Climate Solutions 33 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Federal Lands Across Minnesota, approximately 3.8 million acres are federally owned and managed. This includes United States Forest Service (USFS) lands (primarily the Chippewa and Superior National Forests), National Parks (Voyageurs National Park), and other federal lands (including the Boundary Waters Canoe Area Wilderness, BWCAW). Of this, peat soils have been mapped on about 671,000 acres, primarily in the Superior and Chippewa National Forests. USFS is actively developing research, strategies, and guidance on peatland carbon management and restoration as well as improved forest management techniques for managing the carbon stored in these peatland soils. Major initiatives include developing improved mapping of peatlands and peat soils, especially forested wetlands that may not be adequately mapped by NRCS SSURGO. Perhaps most significantly, there are multiple research initiatives aimed at better understanding fire in peatlands. Although many peatland communities, particularly certain Sphagnum types, can be both resistant to and adapted to natural fire School Trust Lands (STL) and Consolidated regimes, there is a growing need to understand Conservation (Con-Con) lands (discussed below) forest management and other strategies that can are subject to different obligations in statute as minimize the risk of peat carbon loss due to fire, compared with lands acquired directly to meet particularly the more intense fires increasingly specific conservation or natural resource goals. common with climate change. Based on analysis These categories are not mutually exclusive: for of the SSURGO Soil Organic Carbon in the top 100 example, the majority of School Trust Lands are cm layer (Soc0_100), federal lands have a total also designated as State Forest, comprising more carbon stock of at least 302 MMT. than half of the approximately 4 million acres of State Forest lands overall. In addition, the state State Lands owns nearly 3 million acres of county-managed Statewide, the DNR manages a total land lands acquired via tax forfeit, managed by the portfolio of at least 5.6 million acres. This counties where they are located. The majority includes management units designated for a of tax forfeit lands are located in St. Louis, variety of natural resource goals, administered by Koochiching, Aitkin, Itasca, Cass, and Beltrami. different DNR divisions, including State Forests, These are also the counties with the most county- State Parks, Scientific and Natural Areas, and administered peatlands. Wildlife Management Areas. Surface interests and management obligations across these lands School Trust Lands differ according to how the land was acquired More than half of state DNR managed lands are throughout the state’s history. For example, managed on behalf of the Office of School Trust Natural Climate Solutions 34 Playbook for Minnesota Peatlands Photograph © Derek Montgomery ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Land (OSTL), representing almost half of the soils (1.4 million acres, or 55% of total surface DNR’s total managed forest acres (Fernholz et interests) includes the majority of “stagnant” al., 2021). Today this includes 2.5 million acres of (low-lying, wet peatlands) generally not managed surface interests and an additional 1 million acres for timber. However, some forested peatlands or of severed mineral rights. With the establishment lowland conifer systems are considered to have of statehood in 1858, the U.S. Congress originally “productive” stands of black spruce, tamarack, granted Minnesota lands equivalent to sections and northern white cedar. These generally occur 16 and 36 of every township “for the use of on hemic or sapric peat, as opposed to fibric peat schools.” Through a series of “Swamp Acts” (St. Louis County peat inventory, 1980s.) Congress added to these lands, eventually granting Minnesota up to 8.1 million acres. By Approximately 600,000 acres of School Trust the early 20th century, however, much of this Lands are considered “non-productive” in terms land had been exchanged or sold, including most of forestry, but may be subject to mineral leases, of the lands in the southern part of the state most of which correspond to peatland areas. that were considered suitable for agriculture. Currently, active mineral leases on School Trust The remaining lands were largely consolidated Lands peatlands include ~8,700 acres leased for in northern Minnesota as School Trust Lands. peat harvesting and more than 30,000 acres Largely thanks to the inclusion of Swamp Act for industrial minerals, the bulk of which (nearly lands and the process by which less productive 28,000 acres) is for non-ferrous minerals (i.e., northern lands were exchanged for agricultural the lease relating to the proposed Talon Copper- lands in southern Minnesota, more than 60% of Nickel mine near Tamarack, MN). Mineral leases current School Trust Lands (1.4 million acres) are provide the majority of the revenue to the Trust. mapped as having 10% or more histosols. Under the Minnesota Constitution, these are required to Based on analysis of the SSURGO Soil Organic be managed for income to the permanent School Carbon in the top 100 cm layer (Soc0_100), 2.44 Trust, which is primarily generated from mineral million acres of School Trust peatlands statewide royalties, timber, and land sales. have a carbon stock of 400 MMT of carbon just in the top one meter. The top 10 counties for STL Today, all 2.5 million acres of Minnesota School (Koochiching, St Louis, Itasca, Aitkin, Cass, Lake, Trust lands are located within ceded territories Beltrami, Roseau, Cook, and Clearwater) have a with a small subset situated within tribal total stock of 375 MMT and account for 94% of reservations boundaries. More than two million the total SOC in the top 1m. Mean SOC per acre acres, or 92%, of Minnesota’s School Trust Lands on STL in those top 10 counties is at least 161 are located in 10 northern Minnesota counties. MT/acre. School Trust Lands are a substantial share of the total land base in a number of these counties. Consolidated Conservation Lands The remaining School Trust Lands are dispersed Another 1.55 million acres of state-owned throughout other parts of the state, with less land in Minnesota are known as Consolidated- than 500 acres remaining in the southern third Conservation (Con-Con) lands. These lands of the state. represent the bulk of non-School-Trust-Land state-owned peatlands, and stem directly from Of the 2.5 million acres of School Trust Lands, the the attempts to drain the peatlands that ultimately majority are designated as State Forests. The total failed. Accordingly, 64% of these lands—nearly 1 area of overlap between Trust Lands and peat million acres—intersect the histosol layer. The late Natural Climate Solutions 35 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Photograph © Mark Godfrey 1800s and early 1900s saw a peak of drainage engaged in direct land acquisition to meet natural activities when many ditches were being built by resource goals, such as conservation, recreation, local drainage districts in northern Minnesota and economic development. 1.49 million acres in an attempt to convert wetlands to productive have been acquired by the state through purchase, agricultural lands. When many of these projects county board action, gift, condemnation at the failed to meet their financial obligations in the seller’s request, or transfer of custodial control. 1920s and 1930s, these lands were abandoned DNR can only purchase land from willing due to debt or tax delinquency. Many counties sellers. Non-profit land trust organizations can that had assumed responsibility for these debts also choose to purchase lands and then gift also found themselves unable to service them, so property to the state, typically for the purpose of in the late 1990s (in the wake of the Minnesota conservation or recreation designations such as Wetland Conservation Act), ownership was Wildlife Management Areas (WMA), Aquatic consolidated and transferred to the state as Con- Management Areas (AMA), or Scientific and Con lands. Today, income generated from DNR Natural Areas (SNA). management on these lands is split evenly with the counties. While most are managed as state Wildlife Management Areas forestry lands, a significant portion are designated Minnesota’s WMA system started in 1951, when as state wildlife management areas (WMAs). The the State established its “Save the Wetlands” majority of Con-Con lands are in counties that program to buy wetlands and other habitats from also have extensive peatlands: Aitkin, Beltrami, willing sellers to address the alarming loss of Koochiching, Lake of the Woods, Mahnomen, wildlife habitat in the state. Established to protect Marshall, and Roseau. Based on SSURGO, Con- lands and waters that have a high potential for Con lands have a total carbon stock in the top wildlife production, public hunting, trapping, meter of soil of 339 MMT. fishing, and other compatible recreational uses, a large proportion of the state’s ~1.4 million acres Acquired Lands of WMA lands are wetlands (71% intersect the In recent decades, the state of Minnesota has also updated NWI), including peatlands (~40% with Natural Climate Solutions 36 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO mapped histosols). Many of these were acquired as Con-Con lands explicitly because they were largely wetland and therefore not productive for forestry. The largest of these is Red Lake WMA, with approximately 80% of the 324,677-acre WMA having some mapped histosols. Scientific and Natural Areas Minnesota’s SNA program was established to protect natural features of exceptional scientific or educational value including native plant communities, habitats, rare species, and geologic features. As of 2023, Minnesota has designated at least 169 public Scientific and Natural Areas across 216,000 acres, including the 18 original peatland SNAs established by the legislature, in recognition of their special significance to the state. The majority of the state’s largest SNAs are peatlands, including the largest, Red Lake Peatland, at nearly 88,000 acres. Over 177,000 acres of SNAs are mapped as histosols. With a total carbon stock in the top 100 cm of at least 46 MMT, Minnesota’s SNAs already protect some of the highest average carbon stock. Tax Forfeited Lands In addition to the 5.6 million acres of state-owned lands administered by DNR, an additional 2.83 million acres of “tax forfeited lands” (of which nearly one-third are located in St. Louis County) are technically state-owned but administered by the county where they are located. The DNR has oversight and approvals for some timber sales, certain leasing activities, and some sales of the land, but most management is done by the county where the land is located. The title to the lands is held by the state in trust for the respective taxing districts. As with Con-Con lands, many of these lands were abandoned because they were unsuitable for agriculture or forestry. Tax forfeit lands have an estimated total carbon stock in the top 100 cm of 313 MMT, and roughly 1/3 (1 million acres) have peat soils (i.e., mapped histosols). Natural Climate Solutions 37 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Photograph © ColdSnap Photography Estimated extent of drained (fully converted) peatlands In their 2019 GHG inventory, the MPCA listed Unsurprisingly, the majority of peat areas that “cultivated histosols” as the 4th largest statewide have been fully drained and converted are source of GHG emissions. To develop an estimate concentrated south and west of a band that runs of the extent of peatlands and peat soils that have diagonally across the state from northwest to been completely drained and converted to urban, southeast, corresponding to the prairie forest agricultural, or other land uses, we intersected border. These histosol wetlands in the southern soils with 10% or greater histosol content with and western half of Minnesota were almost areas in urban or agricultural land cover (NLCD) entirely drained for agriculture in the late 19th to (See Table 2, Figure 9). early 20th century. Natural Climate Solutions 38 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Estimated extent of partially drained peatlands Previous analyses estimated that up to one- Minnesota: (1) the Red Lake peatlands and sixth of Minnesota’s remaining peatlands are adjacent Rainy River and Lake of the Woods potentially affected by legacy drainage (Ahlering drainages in northern Minnesota and (2) eastern et al., 2021). To refine our estimate of carbon Aitkin and southwestern St. Louis County, mitigation potential from the restoration of including portions of the Mississippi River and partially drained peatlands, we focused our St. Louis River drainages (Figure 9). analysis on peatlands that are impacted by ditches but which have not been fully converted There are many additional smaller patches of (i.e., remaining in natural or perennial cover). We peatlands or peat soils that are only partially then characterized these areas based on soil and impacted by drainage, where publicly or privately other physical properties identified as important maintained ditches occur adjacent to relatively in the literature, as well as layers characterizing intact peatland vegetation located throughout the public land ownership and administration. state, particularly in central Minnesota. Lateral effects reported in the literature range from For the purposes of our peatlands strategy, we 20 m to more than 200 m, and depend on factors summarize peatland ownership categorized such as slope, ditch depth, and properties of the based on the major needs and implications for peat soil (i.e. how quickly water is able to move our feasible strategies: private lands, county tax through the subsurface). BWSR setback guidance forfeit lands, federal and state managed forest for peatlands therefore suggests lateral effects of lands, state WMAs, as well as surface interests 150 m or more for peatlands. To assess the carbon discussed in the previous section such as School mitigation potential of restoring partially drained Trust Lands and Con-Con lands. Nearly one-third peatlands in Minnesota, we intersected the peat of a million of the ditch-impacted histosols occur soil layer with the 150 m lateral effects buffer on publicly administered lands (Tables 3 and 4). around altered watercourses based on BWSR This includes 133,000 acres of ditch-impacted setback guidance and lateral effects reported in the peatlands on state forest lands, more than 84,000 literature (Gerla, 2019; Krause et al., 2021). Using on WMAs, and ~72,000 acres on School Trust information on ditches and altered water courses Lands (Table 4). from the Minnesota state Altered Watercourse Layer, intersected with the SSURGO histosol layer, Finally, we summarize soil organic carbon and and assuming a potential hydrologic impact zone histosols in relation to data on active mineral of 150 m on either side of the ditch, our analysis and peat leases (Table 5) maintained by shows a total footprint of ditched peat soils of MNDNR and available via the public Minnesota 846,000 acres. Limiting the analysis to include geospatial commons. Mining operations impact only acres in wetland or other natural perennial peatlands both through the direct impact of the vegetation results in a statewide opportunity area mine footprint, as well as through alteration of 642,000 acres (Table 2). of downstream hydrology, water quality, and chemistry caused by drainage, subsurface The majority of partially-drained peatlands dewatering, and downstream surcharged releases. are concentrated in two areas of northern Water that has passed through mine tailings also Natural Climate Solutions 39 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Figure 9. Fully drained (converted and/or farmed) and partially drained peatlands in northern Minnesota. Natural Climate Solutions 40 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Table 2. Summarized estimates of partially drained and fully converted peatlands and peat soils in Minnesota based on land cover and intersection with peat soil. NLCD intersection with histosols Partially drained Total drained peat (converted) (within 150 m ditch buffer) Developed (roads, etc) barren land 32,300 116,00 Cropland + 52,775 326,600 Pasture 119,134 151,900 = “Cultivated histosols” 478,000 Perennial cover 642,000 na (wetland, forest, grass, etc) Total (rounded) 846K 594K Table 3. Peat soils and partially drained peat in Minnesota by major ownership/administration. Total Total C stock to Peat acreage Ditched acreage 100cm (MMT) (histosols > 10%) (partially drained) peat Federal 3.5 M 302 671 K 21 K State 5.7 M 910 2.79 M 254 K Tax forfeit (state-owned, 3.0 M 313 1.004 M 56,740 county administered) Reservation / 2.8 M 277 679,650 30,850 Tribal Trust Land Private (implied) 40+ M >2000 >3M acres >300 K Total Statewide 54 M 4487 7.8 M 674 K Table 4. State-owned and administered peat soils and partially drained peat by major designation and surface interest. State designation type: Total Total C stock to Peat acreage Ditched acreage 100cm (MMT) (histosols > 10%) (partially drained) peat State Forest 3.8 M 669 1.67 M 132,550 Wildlife Management Areas 1.38 M 243 615 K 84,240 Scientific & Natural Areas 216 K 46 177 K 17,040 State surface interest/ obligations Consolidated Conservation 1.55 M 339 995 K 138,500 lands School Trust Land 2.5 M 398 1.4 M 72,400 Acquired 2.4 M 178 413 K 1,300 *Totals for state land categories do not match Table 2 as they include just the largest land categories, but are not mutually exclusive. Natural Climate Solutions 41 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Table 5. Peat soils and carbon stocks on lands under active mineral or peat mining lease. carries leached material such as sulfates that can be directly toxic to downstream ecosystems, and/ or accelerate the mobilization of pollutants such as methylmercury (Myrbo et al., 2017). All of these impacts have implications for peat carbon storage, as well as downstream water quality and habitat. The majority of the 27,000 peat soil acres intersecting with “non-ferrous” mining leases occur within the large active lease proposed by Talon for a nickel-copper-cobalt mine near Tamarack, Minnesota, which is currently under environmental review. Data also shows more than 8,000 acres of active peat mining leases, primarily on School Trust Lands, county tax forfeit, and state forestry lands. Many of these leases have lease terms ranging from 15-25 years, with terms running through 2043 or later. Data on historic leases also indicates approximately 4,000 acres of historic, no-longer-active peat leases. Photograph © Derek Montgomery Natural Climate Solutions 42 Playbook for Minnesota Peatlands ESTIMATED PEATLAND SOIL CARBON STOCKS FOR MINNESOTA BASED ON SSURGO Key Takeaways Estimated peatland soil carbon stocks. Previous peat carbon stock estimates of Minnesota did not account for wetlands in the central/south part of the state that also contain high percentages of peat soils. • The amount of carbon stored in soils–particularly in the top layer most likely to be exposed or impacted by conversion, erosion, drainage, drought, or other water table impacts—also represents the amount of carbon that can be lost to the atmosphere as CO2, if wetland systems are degraded through drainage or natural disturbances such as peatland fires. • We created a statewide map of soil organic carbon (SOC) in the top 100 cm of soils, and estimated total carbon in the top one meter statewide at 4.49 Petagrams (Pg). Of that, about 44% of total soil carbon was in histosols. Land Ownership and Carbon Stocks. Of the 7.8 million acres of land identified as having peat soils (10% or more histosol content), roughly 4.5 million (~60%) are in public ownership. This includes: federal (approximately 3.8 million acres) and state lands (about 5.6 million acres). Fully Converted Peatland. The majority of peat areas that have been fully drained and converted are concentrated south and west of a band that runs diagonally across the state from northwest to southeast, corresponding to the prairie forest border. For summaries, see Table 2. Estimated Extent of Partially Drained Peatlands. We estimated the impacts of “Legacy Draining,” or areas that have been ditched in the past but remain in natural vegetation cover, using a 150 m buffer around altered watercourses. For summaries, see Table 3. • The majority of partially-drained peatlands are concentrated in two areas of northern Minnesota: (1) the Red Lake peatlands and adjacent Rainy River and Lake of the Woods drainages in northern Minnesota and (2) eastern Aitkin and southwestern St. Louis County, including portions of the Mississippi River and St. Louis River drainages (Figure 9). Natural Climate Solutions 43 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA Photograph © Corey Brouwer Estimating Carbon Mitigation Potential of Peatland Restoration in Minnesota The climate mitigation benefit of any specific land water table to restore inundated conditions, re- use change, restoration or management practice wetting drained/degraded peatlands generally (i.e. “NCS pathway”) is often calculated as the sum reduces CO2 emissions but increases CH4 of the changes in GHG emissions by gas for each of emissions. This tradeoff is not straightforward, the individual emissions sources under the avoided as CH4 is a near-term climate forcer, with a conversion or restoration scenario, as compared with large radiative efficiency but a short atmospheric the ‘counterfactual’, i.e. baseline scenario without lifetime. CO2 however, is a long-term climate intervention, over some relevant time period. forcer, with a smaller radiative efficiency but a long atmospheric lifetime. Quantifying the climate mitigation potential of peatland restoration is particularly challenging Increasingly, methodologies for estimating climate for many reasons. The factors and processes that impacts from different scenarios recommend govern carbon inputs and outputs (collectively aggregating short-lived climate pollutants “fluxes”) are highly variable and inconsistent at (e.g. CH4) separately from long-lived, stable multiple spatial and temporal scales (Bedard- climate pollutants (e.g. CO2). To account for Haughn et al., 2006; Phillips and Beeri, 2008; the higher short-term warming potential of Tangen et al., 2015; Tangen and Bansal, 2019). CH4, flux values for CH4 are often multiplied by a factor of 28-35 to express them as CO2 As discussed earlier, because restoration of equivalent (CO2e). Wherever CH4 fluxes are drained peatlands typically requires raising the within an order of magnitude of CO2 fluxes, the Natural Climate Solutions 44 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA accuracy of estimates of GHG flux expressed emissions using a single scaling factor are overly as CO2e, particularly in the short-term, will be simplistic and can be misleading particularly over highly sensitive to CH4 flux, for which published longer time scales. values from Minnesota peatlands are limited Recent guidance produced by MPCA (2022) and highly variable. At the same time, because reported avoided GHG emission from retirement the atmospheric lifetime of GHGs such as and re-wetting of farmed peatlands based on CH4 and CO2 differ significantly, their relative the difference between emissions from drained radiative forcing expressed as CO2-e also differ cropped peatland soils (i.e., histosols) and re- over time, because the warming effect of CH4 wetted, restored histosols. GHG emissions dissipates to zero over time, whereas the warming reductions accounted for in calculating the effect of long-lived pollutants is cumulative and baseline (pre-restoration) were comprehensive largely perpetual. Therefore, metrics that equate and included CO2 emissions from drainage Table 6. Estimated climate mitigation potential from re-wetting and restoring peatlands on cropped and pastured histosols Scenario Restoration Change in emissions Total Mt CO2e/year potential (acres) from avoided loss + restored sequestration (Mt CO2e/ac/yr) Re-wet cropped histosols 326,600 1.34 437,600 Re-wet pastured histosols 151,900 0.95 144,300 Total 581,900 Emissions avoided from re-wetting and restoring peatlands drained for agriculture (mineralization) plus tillage and nitrogen summed as per the recommended approach fertilization, N2O and CO2 emissions from for national emissions reporting. The implied fuel used in crop production and during the annual emissions reductions from re-wetting are manufacture of synthetic agricultural fertilizers, shown in Table 6 for both cropped and pastured pesticides, and fuels used on-farm. For the histosols. Based on our estimate of the area restoration scenario, the estimate accounted of cropped and pastured histosols, our revised for CH4 release post re-wetting, using the 28x estimate of carbon emissions avoided from multiplier for CH4 warming potential. Avoided restoration and re-wetting of farmed histosols is emissions were averaged over 20 years and ~582K Mt CO2e/year. Natural Climate Solutions 45 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA Assessing carbon mitigation potential of restoring partially drained peatlands In our initial statewide NCS analysis (Ahlering et al., 2021), we reported combined avoided carbon emissions from avoided peatland conversion and peatland restoration at 450,000 Mt CO2e per year. This was based on applying a single avoided emissions factor—expressed in CO2 equivalents, CO2e—to one estimate of annual area at risk of conversion, and another single emissions factor for annual sequestration potential from peatland restoration and re-wetting, multiplied by our initial area estimate of half a million acres of restorable peatlands statewide. For estimating change in emissions from re-wetting partially drained peatlands, we used a relatively mid-range estimate based on a wide range of values reported in the literature for annual peatland sequestration potential. This was not, however, compared to a specific counterfactual, and was oversimplified with respect to CO2 versus CH4. For the purposes of this Peatland Playbook, our intent is not just to improve our areal estimates of restoration and re-wetting opportunity, but also to refine our estimates of avoided loss and sequestration potential subdivided by peatland type, land cover, restoration status, and other important biophysical variables reported in the literature. We had also hoped to assess the relative importance over time of the tradeoff between CO2 and CH4 emissions from different restoration approaches, and to incorporate initial results from our greenhouse gas (GHG) monitoring at restoration sites. However, those results will instead be included in future publications. There is no shortage of relevant or representative estimates of annual sequestration and/or emissions reported in the literature for both Photograph © Derek Montgomery Natural Climate Solutions 46 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA CO2 and CH4 from different peatland and in temperature, soil pH, water table, vegetation land cover types in Minnesota, as summarized composition, and seasonal growth patterns. here. However, there is considerable overlap in the range of estimates reported for each. Peatland vegetation, nutrient status, depth to Furthermore, although research is ongoing, there water table, mean annual temperature, and pH are no completed comparable studies of GHG flux are all important factors (Abdalla et al., 2016), from re-wetted peatlands in Minnesota, on either but depth to water table and nutrient status/pH fully or partially-drained sites. are generally reported to be the most significant (Turetsky et al., 2014). Based on these observed There is a growing body of studies from Canada relationships, and the relative simplicity of relevant to the restoration of fully drained monitoring vegetation compared with GHG flux, peatlands that were previously converted some researchers propose and pilot methods to for agriculture or peat mining, including a index emissions factors based on vegetation type few approaches that do develop separate or water table (Bona et al., 2020; Couwenberg et comprehensive estimates accounting for al., 2011) . individual differences in radiative forcing and atmospheric lifetimes for CO2 and CH4 across In 2023, carbon advisory firm Terracarbon different peatland types. Relevant estimates come conducted a pilot analysis for TNC, assessing from an extensive literature review conducted the potential for carbon markets to finance by Wilson and colleagues (2016), evaluating peatland re-wetting projects under the approved emissions factors associated with re-wetting, Verra VM0036 carbon standard (Verra VCS expanding on the 2013 Wetlands Supplement Carbon methodology standard, 2016). Although to the IPCC (Drösler et al., 2013). Their work the standard was developed and approved for confirmed the general trend of decreasing CO2 projects generating climate benefits via avoided emissions from re-wetting of drained organic emissions of peatlands that have been drained soils, as well as the strong link between water for forestry, peat extraction, or agriculture, to table depth and both CO2 and CH4 emissions. date we are unaware of any projects that have They also reported separate emissions reductions been fully piloted using this standard. The estimates, incorporating all components of GHG VM0036 methodology allows two methods for emissions (CO2, DOC, CH4, N2O), for re-wetting estimating GHG emissions due to peat drainage of drained nutrient poor versus nutrient rich in the baseline scenario: the GEST approach, forested peatlands (0.49 and 0.64 Mt CO2e/ which estimates GHG fluxes based on indicator ac /yr, respectively (Wilson et al., 2016). A vegetation types, or the use of water table levels selection of relevant flux values reported in the as a proxy. However, because we have not fully literature for CO2 and CH4 from Minnesota, established significant models for indexing neighboring regions, or similar peatland systems fluxes from Minnesota peatlands to mapped is summarized in Table 7. The published values indicator vegetation types, TerraCarbon used reveal a considerable range in CO2 flux, from the water table proxy approach based on the -0.76 to 0.04 t CO2e/ac/yr, and highlight regression model developed by Couwenberg et uncertainties in developing climate mitigation al. (2011) using CO4 and CH4 emissions data estimates appropriate for our region. In general, from 10 different studies in northern temperate/ variability in annual average estimates relates to hemi-boreal climates. Using an assumption for the fact that emissions and fluxes are dynamic a hypothetical project area based loosely on an across the seasons in response to fluctuations existing WMA and water level logger data from Natural Climate Solutions 47 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA the Sax- Zim Bog restoration, they estimated an the Canadian emissions modeling approach for area-wide impact for ditch restoration on the peatlands described in Webster et al. (2018) and water table of 5 cm, i.e., raising the water table Bona et al. (2020). from -20 cm to -15 cm. They applied a linear regression model for comparing pre- (drained) In the context of carbon finance, re-wetting vs. post-restoration (plugging and filling ditches) scenarios involving a reduction in emissions fluxes based on the predicted increase in water rather than restoration of a net carbon sink, table x across the restored site: are subject to the concept of “peat depletion” time, i.e., the amount of time until a drained peat soil is fully oxidized, recognizing there is a CO2: y = -752 * (x – 4750) limit on the number of years that a project can unit: x1,000 kg CO2 per hectare per year claim emissions reductions from re-wetting. Regardless, the appropriate comparison for estimating climate mitigation benefits of CH4: y = 16.7 * (x + 20) re-wetting and restoration is the difference unit: kg CH4 per hectare per year between the baseline (no action) scenario and the restoration scenario, as summarized by the Using the above equations, they derived an “CO2e emissions avoided” in Table 8. estimated net difference in baseline versus post- restoration-project scenarios of 0.57 Mt CO2e/ Although we are continuing to develop more ac/yr (1.4 Mg/ha/year), which is within the range refined methods for estimating climate mitigation of emission factors (EFs) from restored peatlands benefits of peatland restoration, we include here a in Table 7. revised range of estimates based on the potential climate mitigation impact reported by Krause et al. Although the Couwenberg regression estimates (2021). Based on updated estimates of the extent used for the above analysis were preliminary of histosol soils and other high carbon stock soil and oversimplified, the approach does offer types statewide that are within the lateral effects the potential for developing region-specific zone of altered drainage channels, we estimate relationships for scaling as well as eventual the total potential climate mitigation benefits of project reporting and verification. Furthermore, restoring all partially-drained peatland statewide Couwenberg also presented a regression for at more than one-half million Mt per year. The indexing the density of aerenchymous leaves potential for peatland restoration on public land containing specialized structures for providing alone would be 282,000 Mt (Table 9). oxygen to submerged roots within peat vegetation, which serves as the basis for the Our estimates assume, as did Krause and GEST approach outlined in VM0036. Using the colleagues, that gains from avoided loss of existing vegetative assessment of the GEST approach in carbon from partially drained peatlands and the conjunction with improved statewide vegetation potential sequestration of carbon at restored mapping and/or modeling may allow for a sites would be linearly additive (Krause et al., more accurate, spatially explicit, or dynamic 2021; USFWS, 2010). Although this is likely a statewide assessment of climate benefits from valid assumption over longer periods of time, we restoration over time and in response to changing acknowledge that the bulk of carbon losses likely climate and vegetation conditions, similar to occurred in the initial decades following drainage. Natural Climate Solutions 48 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA Table 7. Review of carbon dioxide fluxes reported from published studies of peatlands in Minnesota and other relevant northern peatlands compared to Tier 1 IPCC default EF (IPCC, 2014). a Negative values indicate sequestration; positive values represent emissions or loss to the atmosphere b Marcell Experimental Forest located in northern Minnesota c Summarized in Kolka et al. (2018) d Summarized in Strack l (2023) Natural Climate Solutions 49 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA Table 8. Review of GHG emissions avoided (expressed as CO2 equivalents, including C as CO2 and CH4 and N2O) reported for re-wetting and restoration of partially drained peatlands in Minnesota a Mean values for peatland restoration reported in Appendix II, converted from g C m2/yr b Positive number indicates source to atmosphere; negative indicates net uptake from atmosphere or net increase in sink) In closing, it is worth reiterating that multiple considered essential to reverse, slow or avoid recent comprehensive reviews have concluded irreversible carbon losses from these enormous that wetlands are a long-term natural climate global carbon stores (Humpenöder et al., solution, and that even when accounting for 2020; Nugent et al., 2019); with the caveat that the higher short-term warming effect of CH4, research evaluation and adaptive monitoring are the cumulative radiative forcing from CO2 (and also critical to resolve uncertainties and expedite sometimes N2O emissions) from unrestored learning around successful techniques (Loisel wetlands far exceeds the temporary warming and Gallego-Sala, 2022). effect from CH4 emissions of restored wetlands, including peat lands (see Figure 3; Günther et al., 2020; Julie Loisel et al., 2021; Neubauer and Verhoeven, 2019; Nyberg et al., 2022; Strack et al., 2022). Thus, both protection and immediate active restoration of peatlands are still Natural Climate Solutions 50 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA Table 9. Estimated climate mitigation potential of restoring partially drained peatlands through ditch restoration and peatland re-wetting. Estimates: Restorable ditch Avoided Potential Avoided loss Total Mt impacted peat, ongoing loss sequestration + restored CO2e /year acres (ha) rate (Mt rate (Mt CO2e sequestration CO2e ac/yr) ac/yr) (Mt CO2e /ac/ yr) Public land 332,000 0.46 0.39 0.85 282,200 Minnesota 642,000 0.46 0.39 0.85 545,700 Total *compare to 306,532 0.46 0.39 0.85 260,500 Krause et al (124,102) 2021 Photograph © Derek Montgomery Natural Climate Solutions 51 Playbook for Minnesota Peatlands ESTIMATING CARBON MITIGATION POTENTIAL OF PEATLAND RESTORATION IN MINNESOTA Key Takeaways • Previous academic literature confirms a strong link between both re-wetting of drained organic soils and increasing the water table to a long-term reduction in CO2 emissions, but a short-term increase in CH4 emissions. • Estimating which one has a stronger impact is difficult because of variation in carbon fluxes. However, general evidence indicates the long-term benefits of CO2 reduction outweighs the short-term impacts from CH4 emission and that re-wetting peatlands will result in a net carbon sink. • Based on updated estimates of the extent of histosol soils and other high carbon stock soil types statewide that are within the lateral effects zone of altered drainage channels, we estimate the total potential climate mitigation benefits of restoring all partially-drained peatland statewide at more than one-half million Mt per year. The potential for peatland restoration on public land alone would be 282,000 Mt (Table 9). • Re-wetting of partially drained northern temperate peatlands represents a significant NCS pathway in Minnesota due to the presence of high remaining carbon stocks, the ongoing threat of degradation from legacy drainage, and net positive GHG dynamics of restoring ditched peat. Photograph © Derek Montgomery Natural Climate Solutions 52 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION Photograph © Derek Montgomery Scaling Up Implementation: Exploring the Biophysical, Economic, and Socio-political Feasibility of Peatland Restoration Many factors affect the feasibility of peatland peatland restoration, we are continuing to refine restoration, including ecological type, our understanding of carbon mitigation potential, biophysical and landscape setting, technical biophysical feasibility, and co-benefits from ditch complexity, and social, economic, institutional, plugging and peatland re-wetting across the and governance practices. state’s peatland ownership mix. In addition to identifying priority areas for restoration, TNC is learning from past research Biophysical feasibility and restoration efforts to improve the outcomes of future restoration projects. As part of this, Biophysical feasibility refers to the influence of we are working to synthesize lessons learned biological, landscape, chemical, and other physical from initial field data from the TNC-led study conditions and settings on the potential for and other research projects. This will help to restoration success. Success in this case refers to design and implement an effective monitoring restoring peatland ecosystems as a carbon sink, and evaluation study to address key remaining or at least substantially reducing net emissions. uncertainties associated with hydrologic Peatland restoration is often centered around restoration of restored peatlands in Minnesota restoring hydrology and can be as simple and (see Restoration Effectiveness Study). To improve straightforward as plugging a ditch (something our estimate of the potential climate benefits of that might even happen naturally due to beaver activity or lack of maintenance). There are many Natural Climate Solutions 53 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION examples of successful peatland restoration in reestablishing the hydrology and chemistry projects globally, including some in Minnesota, that supported the pre-altered wetland vegetation that have led to both technical guidance and a communities. Because peatland vegetation type growing body of experience. These range from the is structured by the interaction of water source, simple restoration of partially drained peatlands chemical properties, hydrologic regime, and peat where most of the peatland is intact to the characteristics, it can be difficult to restore the extremely complicated technical and engineering original vegetation type if the correct hydrology designs needed to restore fully drained and cannot be reestablished due to alterations converted peatlands that have been farmed, from roads, drainage, or other factors. Plant mined, or afforested. However, in most cases communities can influence GHG flux directly, for these examples have not been evaluated in terms example by transporting CH4 through structures of their net impact on greenhouse gas (GHG) for providing oxygen to roots called aerenchyma, flux, but instead for how well they have restored or indirectly through changes to the soil hydrology or vegetation. Fortunately, the evidence environment (Escobar et al., 2022; Robroek et al., from Canada, northern Europe, and elsewhere 2015; Ward et al., 2013) . While it’s possible to say (including our initial study findings in Minnesota) that generally Sphagnum tends to decrease and suggests that the latter in most cases is indicative sedges and grasses increase GHG fluxes, studies of the former, particularly for Sphagnum-moss- have showed mixed results. dominated communities. Some wetland/peatland types are likely easier A number of physical, biological, and to restore than others, both in terms of restoring environmental factors affect the feasibility of peatland vegetation as well as reestablishing peatland restoration. These include factors net GHG uptake. For example, restoration of such as peatland type, the restoration size, a carbon sink in peatlands appears to have a ditch properties, catchment position, hydrologic greater probability of success for Minnesota’s complexity (e.g. drainage area, degree of acid peatland or open Sphagnum-dominated hydrologic alteration, level of peat degradation, communities than for fens and open rich time since drainage and/or maintenance, and peatlands. Sphagnum moss is a key plant genus, size (width, depth, and slope) and capacity of referred to by some as an “ecosystem engineer” the ditches). (Rochefort, 2000) that strongly influences many of the hydrologic, biogeochemical, and These physical factors affect the degree of carbon-accumulating functions of peatlands. difficulty in restoring the water table and pre- Sphagnum moss can create conditions that few drainage hydrology as well. other plants can thrive in (acidic, nutrient-poor, and cold) making bogs much less vulnerable to Peatland plant communities play a critical role in invasion. Sphagnum mosses are more resistant the peatland carbon sink function, so restoration to decomposition compared to sedges and other feasibility depends on the ability to reestablish vascular plants and thereby retain more carbon vegetation. Vegetation reestablishment is over time (Rydin et al., 2013). Sphagnum moss influenced by many factors, including the forms a cap over bogs, limiting CH4 release where availability of local seed source or transplants, it grows across the surface of the water or forms the influence of invasive species are at the site hummocks above the water table, intercepting (e.g. cattails, Typha sp.; or reed canary grass, CH4 (Kox et al. 2021, Zhang et al. 2021, Tian et Phalaris arundinacea), and the degree of difficulty al. 2023). Natural Climate Solutions 54 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION On the other hand, CH4 emissions are generally The complex hydrology and higher pH of fens higher from fens than from acidic nutrient-poor also makes them more vulnerable to invasion bogs (Abdalla et al., 2016; Moore and Knowles, by non-peatland emergent wetland plants that 1989) due to higher pH, warmer subsurface can be significant CH4 emitters (phragmites, temperatures from groundwater flow, and more cattails, reed canary grass). Restoration projects emergent vegetation, such as sedges, which with more open water favor more bubbling up transmit CH4 to the air more effectively. Fens are of CH4 (ebullition) and/or transport in plants often more difficult to restore because of complex that can lead to higher and more variable CH4 groundwater flow paths from the watershed release in fens compared to bogs. Turetsky et al. and their greater diversity of rare plants, and the (2014) found that the CH4 flux from fens is more complex fen and bog hydrology of northwestern sensitive to the vegetation type present and less Minnesota’s extensive patterned peatlands sensitive to soil temperature than fluxes from bog have resulted in little natural recovery of pre- or swamp ecosystems. Still, fens are more often drainage peatland conditions even where ditches protected and restored for their unique and rare have not been maintained for many decades. plant community assemblages, e.g. calcareous This has also made it difficult to restore pre- fens, a rare type of peatland fed by groundwater impact vegetation and hydrology even in many low in oxygen and rich in calcium and magnesium. places where restoration has been attempted. These fragile ecosystems are afforded special Photograph © Derek Montgomery Natural Climate Solutions 55 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION protections under the Minnesota Wetland Conservation Act. Recognizing the importance of Sphagnum mosses to forested and open bog systems, BWSR provides technical guidance on peatland restoration both in locations where peat has been mined or where it is suitable to reestablish moss (MN BWSR, 2012). The guidance also discusses the equipment and materials needed to conduct large-scale peatland restoration, which also varies depending on how extensive physical and hydrologic alterations have been at the site, the degree and condition of peat remaining at the site, and the availability of nearby donor material such as Sphagnum and peatland plant communities needed to re-colonize the site. Restoration sites adjacent to larger intact peatland areas will likely require less time and fewer resources to reestablish, since they are likely less disturbed and have a nearby source of plants to colonize the site. For peatlands mined for peat moss, considerable guidance and expertise has also been developed in Canada with the Moss Layer Transfer Technique for restoring peatlands, including demonstrating higher priority for avoiding irreversible carbon recovery of net carbon sequestration after 10-20 loss compared to hemic or sapric peats, as well years (Quinty et al., 2020). This method should as more technically feasible to restore (Krause, also work in many cases for drained, farmed, or 2020). Because peatland drainage causes the cultivated peatlands once peatland hydrology has land surface to shrink or subside over time, the been restored. The BWSR guidance references the ground surface can be lowered by over a meter in Canadian technique as well as experience gained some cases where peatlands have been drained from application of the approach in Minnesota for many decades (Boelter, 1972; Hökkä et al., at the Fens Wetland Bank site established by 2020; Nieminen et al., 2018; Reagan, 2023). The the Natural Resources Research Institute (NRRI; loss of peat volume and lower elevation creates affiliated with University of Minnesota-Duluth). several limitations for restoration. The loss of this amount of peat means that it would likely Another major factor influencing restoration require decades or centuries to re-accumulate to feasibility is the degree to which peat loss or the former elevation. From a practical standpoint, degradation has already occurred. The rate of the lowered ground surface elevation means that carbon loss appears to be most rapid during the when the ditch is blocked, the area is often re- initial phase after drainage or conversion, and flooded as open water. This changes the plant therefore peatlands composed of less-degraded community type and has been found to favor CH4 or decomposed fibric peat should be both a release. It can be difficult to recover a Sphagnum- Natural Climate Solutions 56 Playbook for Minnesota Peatlands Photograph © Derek Montgomery EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION dominated bog in those open water areas, if it is open water areas and ditch-adjacent areas with too deep for the Sphagnum to re-colonize. peatland vegetation, especially reestablishment of Sphagnum moss communities. At the 24,000- Blocking ditches is generally key to restoring acre Lake Superior Wetland Bank, ditch checks peatland hydrology (Gatis et al., 2020; Holden et were required at intervals along the ditch al., 2006; Price et al., 2003). While ditch blocking coinciding with every one-foot drop in elevation. typically results in a more stable and sustainable hydrological regime by increasing baseflow from “The minimum standard for ditch disablement the peatland and reducing peak runoff rates and is the construction of ditch checks, and the sediment export (Gatis et al., 2020)), this is not placement of a minimum of 200 contiguous always guaranteed. One of the lessons learned linear feet upstream, and 100 contiguous feet from the restoration at Sax-Zim bog and other downstream of natural material to completely fill projects in the northern US and Canada is that the channel for the entire width and to the top of blocking ditches alone does not restore all the the natural bank.” (EIP, 2015). ecological functions and benefits that intact Active transplantation or seeding of moss cuttings peatlands provide. As previously mentioned, if may also help accelerate vegetation recovery, blocking ditches creates large areas of open particularly if—as was done at the Lake Superior water this may create increased hotspots of Wetland Bank—ditch fill materials are obtained CH4 release. on-site from areas adjacent to the ditches as part of the restoration itself where re-wetting would Managers of future projects will want to consider have likely led to some tree mortality in any case. the costs and benefits of simple ditch blocks Ditch fill materials can come, for example, from versus more extensive restoration designs that thinning of tamarack or spruce trees, together require more earth-moving. If there are large, with their root wads and understory vegetation. deep open ditches, they may need to be filled with logs, peat, or soil (see the BWSR wetland Feasibility factors that may be relevant to restoration guidance). Some ditches could be prioritizing based on degree of difficulty and re-meandered into a shallower swale that could complexity include watershed position and be revegetated more easily. Alternatively, or in context, slope, and existing vegetation. Factors addition, grading the filled ditches to make them that maximize the carbon gains and co-benefits shallower may also help reduce open water and from hydrologic restoration of peat while accelerate vegetation recovery, though that adds minimizing the risk of impacts to adjacent working considerably to the project cost. lands and infrastructure should in theory help identify better restoration opportunities. Factors For restoring partially drained peatlands through such as the amount of road or other infrastructure ditch closure, feasibility (and budgets) for that need to be preserved and the necessity restoration will likely vary significantly across of limiting impacts to adjacent properties may restoration sites depending on factors such increase the cost, difficulty, and complexity, while as ditch size, depth, conveyance capacity, and lowering the feasibility of restoration success. drainage slope. For partially-drained peatlands Once restoration opportunity areas have been impacted by larger ditch networks, such as the identified, each project typically requires a Lake Superior Wetland Bank site in the Sax-Zim high degree of site-level detailed assessment. Bog it is likely necessary to do extensive filling of This includes LiDAR analysis of ditch depth, ditch segments in order to accelerate filling-in of slopes, and orientation in relation to surface and Natural Climate Solutions 57 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION subsurface flow hydrology. A hydrologic study typically has to be done to show that the project won’t flood out adjacent roads, buildings or other infrastructure. When assessing the effectiveness of restoration efforts, it is important to consider that the climate benefits of peatland re-wetting are time- dependent, with as much as 15-30 years required for re-wetted peatlands to resume functioning like intact peatlands (Escobar et al., 2022). During this time, changes in gas flux are not linear. Better accounting for temporal aspects of peatland recovery is key for accurately estimating climate benefits, as emissions factors are often derived from a short snapshot that may over- or underestimate rewetting GHG benefits depending on the post-restoration time of a peatland (Kalhori et al., 2024). While our assessment of peatland restoration success focuses on climate mitigation, peatland restoration also offers a range of other potential co-benefits. For example, restoration can impact mercury export and improve water quality, reduce wildfire risk, and produce economic benefits. However, research focused on the climate impacts of peatland protection and restoration are rarely integrated with an investigation of co-impacts, and a better understanding co-benefits could help increase stakeholder buy-in and achieve greater implementation of protection and restoration projects. Also impacting the effectiveness of peatland restoration efforts are the future impacts of climate change. Peatland responses to rising temperatures and changing precipitation patterns are complex, involving many feedbacks and non- linear responses between plant communities, soil properties, and soil microbial communities, which all affect carbon balance (Allison and Treseder, 2011). The SPRUCE (Spruce and Peatland Responses Under Changing Environments) project, a large-scale climate manipulation Natural Climate Solutions 58 Playbook for Minnesota Peatlands Photograph © Derek Montgomery EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION experiment in northern Minnesota, is investigating Economic feasibility: Costs changes to the entire peatland ecosystem above and belowground, and has shown the potential Beyond the biophysical constraints, many factors for significant disruption of peatland ecosystems impact the cost and feasibility of peatland and loss of carbon under projected warming restoration, including land ownership, land use, scenarios (Hanson et al., 2020). However, climate infrastructure such as roads and utility corridors, manipulation experiments of this are rare, and cultural history and beliefs, local and regional studies examining interactions between peatland economic factors, taxation and drainage policy, drainage and climate change are lacking. Climate and funding availability. Projects can range from change is also causing increased frequency and relatively inexpensive options such as passive severity of wildfires (IPCC, 2022: Climate Change ditch abandonment to more costly interventions 2022: Impacts, Adaptation and Vulnerability Working such as ditch plugging and active seeding of Group II contribution to the IPCC Sixth Assessment peat to ensure full restoration. While the costs Report of the Intergovernmental Panel on Climate described in this section represent key on-the- Change, 2022) and increase the susceptibility ground project estimates, they do not include of peatlands to fire (Loisel et al., 2021; Turetsky other essential expenses related to project et al., 2015, 2011), further threatening peatland management, planning, and outreach. carbon stocks, with fire potentially contributing peatland carbon emissions of the same order For peatland restoration projects, whether on as peat decomposition (Turetsky et al., 2015). public or private land, the BWSR technical guide Restoring and protecting peatlands can decrease estimates costs for site preparation, donor their fire susceptibility, but wildfire has not been material harvest, installation, and maintenance for well-incorporated into our understanding of peatland restoration at $1,200-$3,000 per acre. Minnesota peatlands. However, prices have likely increased in the years since the BWSR guide was published. While significant guidance on peatland restoration techniques exists, many uncertainties remain On private lands, the cost of purchasing the land with respect to the magnitude of the climate or obtaining easements increases project costs benefits of restoration in Minnesota, quantifying considerably. In northern Minnesota, land may the underlying drivers of GHG flux, how these be $1,000-$3,000 per acre, but in southern impacts may change under future climate change Minnesota farmland land values can exceed scenarios, and which co-benefits restoration may $10,000 per acre. However, in Central Minnesota, provide. TNC is conducting ongoing field research TNC’s partnership with the U.S. Fish and Wildlife to fill these knowledge gaps, refining regionally- Service (USFWS) has helped promote lower-cost specific emissions factors, and developing models restoration on private land by forgoing easements for estimating peatland GHG fluxes based on using low-tech designs and minimal seeding. For site-specific conditions. The findings of this restoration, protection, and avoided conversion work will help to assess the feasibility of future involving the acquisition of fee title, prices of restoration projects and identify the highest $500-$1,000/acre can be expected for wetland priority peatlands. acreage in Northern Minnesota. Natural Climate Solutions 59 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION Large-scale projects are typically more Most projects across the state will require a economical because of fixed costs for equipment hydrologic analysis and modeling to demonstrate mobilization, design, and erosion control. The that the wetland restoration won’t flood out fixed costs for mobilization often start in the range adjacent roads, trails, homes, or other structures. of $2,000-$5,000 for small equipment but can This could add $5,000 to $20,000 or more for be as much as $10,000 or more for large pieces of very complex projects. Management and long-term earth-moving equipment. maintenance costs also need to be considered. This may be in the range of $1,000-$5,000 The other major cost in peatland restoration per year depending on the site. Hydrologic and is creating a ditch plug, which can range from carbon monitoring add additional costs. Currently, a few thousand dollars to up to $20,000, as hydrologic monitoring is required for mitigation seen in a project in Anoka County, Minnesota. wetlands to demonstrate the establishment of Drain tile plugs may also be required in southern wetland hydrology for a period of five years. agricultural wetlands of Minnesota, but are not For example, TNC is conducting monitoring of usually present in northern Minnesota. hydrology and CO2 emissions from two sites at an estimated cost of $2,000-$5,000 per site per year. Photograph © Derek Montgomery Natural Climate Solutions 60 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION In theory, restoring drained peatlands on public Sites on public lands often still contain some lands through a legal ditch abandonment pro- intact peat or native plant coverage, making them comparatively more cost-effective to cess has the potential to be most cost-effective restore. However, some peatlands on School because this strategy has the least opportunity Trust Lands support mining and forestry interests cost and because producing climate benefits on that make them more economically valuable publicly held peatlands is consistent with high- and difficult to do peatland restoration on. In est and best use of public lands. However, many contrast, restoration on farmed sites (and peat mine reclamation sites) can sometimes be very ditches, even when not actively maintained, are expensive, as they often require peat revegetation not healing themselves. This strategy may work and transplantation in addition to reestablishment best in limited locations, or in conjunction with of peat hydrology. However, these farmed other restoration initiatives. peatlands are still important to consider for restoration, as described in Box 4. Partially restored peatlands © TNC Natural Climate Solutions 61 Playbook for Minnesota Peatlands Box. 4 Most farmed peatlands (cropped, pastured, or cultivated histosols, and organic soil wetlands) in Minnesota are in private ownership. Although peatland restoration in these contexts is often very expensive, due both to land/opportunity cost as well as extensive engineering, hydrologic, and technical costs of restoration, wetland restoration is a major strategy for the TNC’s Resilient Waters program in Minnesota. Freshwater priorities for the chapter include promoting sustainable land and water management and climate resilience by restoring soil health, floodplain/riparian and wetland habitat. Restoring peatlands and wetlands in these more productive agricultural regions is often more costly, but wetland restoration projects in these contexts may produce, on a per-acre basis, higher carbon sequestration co-benefits in the short-term than restoration in northern peatlands, due to a warmer climate, more productive soils, and different vegetation types. In some cases, contrary to our initial assumptions, the lower legal and institutional complexity of smaller projects with less complex ownership patterns may even make the cost and feasibility comparable to restoration on public lands. In fact, multiple wetland restoration programs in Minnesota, from the WRP to wetland banking to FWS wetland easements— along with state Outdoor Heritage and Clean Water Funds generated by Minnesota’s Clean Water, Land, and Legacy Amendment— have in recent years been driving significant increases in wetland restoration activities in southern and central Minnesota. A significant percentage of these projects have been completed on soils mapped as high organic/ histosols. Economic feasibility: Funding opportunities At present, state and federal funds have played a federal level, the Inflation Reduction Act provides key role in funding many of the limited peatland some opportunities for securing funding for restoration projects that are planned across the peatland restoration, and we hope to continue state. As regional and national climate priorities working with partners to secure and implement shift to include the importance of natural and related proposals. Finally, there is a significant working lands in climate change mitigation, we opportunity to engage directly with county have seen some sources of funding set aside for drainage authorities seeking to reduce the long- peatland research and restoration. On the state term maintenance burden of public drainage level, this includes funding for the DNR’s pilot systems on taxpayers, local and state government. restoration program, a state Legislative-Citizen Commission on Minnesota Resources (LCCMR) Though government funding has served as a key grant awarded to the University of Minnesota resource, we will likely need to pursue additional for research on northern peatlands, and BWSR’s financial pathways in order to adequately scale new RIM (Reinvest in Minnesota) program for peatland restoration. One such opportunity could peatland restoration on private lands. At the be though the use of carbon markets, where Natural Climate Solutions 62 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION project proponents could sell carbon credits from avoided carbon loss in peatlands after restoration. Carbon financing in Minnesota is in the early stages, even on private lands. There is a project piloting a Family Forest Carbon Program for financing carbon investments on private lands, which might provide a framework for compensating landowners for peatland restoration on private land in the future. Given that a significant portion of publicly owned drainage-impacted peat is located on county tax forfeit or state School Trust Land, the state of Minnesota has been actively exploring a mechanism for Payments for Ecosystem Services (PES)—including participation in voluntary carbon markets—as a way to provide revenue to the counties or to the state School Trust Fund. Recent legislative changes allow for a county auditor, as directed by the county board, to lease tax-forfeited land under the terms and conditions prescribed by the county board for the purposes of investigating, analyzing, and developing conservation easements that provide ecosystem services. However, to date there is no enabling legislation allowing for carbon financing on state-owned and administered lands. The OSTL is actively exploring the potential for carbon financing to generate revenue on School Trust Land as part of its 25- year asset management plan. The DNR, which is currently responsible for administering these lands, including revenue-generating activities such as peat mining and timber harvest, is coordinating internal discussions to understand the implications of pursuing this strategy. As mentioned earlier, a verified carbon standard (VCS) for peatland restoration—the Verra VM0036 “Methodology for Re-wetting Drained Temperate Peatlands”—does already exist as a means to enable potential peat re-wetting projects through verified carbon markets. Photograph © Derek Montgomery Natural Climate Solutions 63 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION However, to date there are no examples of suggests that most projects interested in using peatland restoration projects that have been carbon markets to fund restoration would also piloted under this standard, in Minnesota or need significant outside financial investments, anywhere else. While more information would such as grant funding or private philanthropy be needed before moving forward with a project, support. See Box 5 for more details about this early analysis shows that this could work in some analysis process, and Table 10 for a sample list of areas where the land use and history meets anticipated costs. applicability considerations. The Nature Conservancy, in partnership with TerraCarbon, recently conducted an exploratory analysis of the potential to fund restoration of partially drained peatlands in Minnesota under the VM0036 standard, as discussed in the previous section on estimating GHG reduction potential from restoration (Ericksen et al., Unpublished). The initial assessment confirmed that the largest restoration opportunity areas that meet conditions for a possible carbon project are on state-owned lands. Within the VM0036 standard, there are a few additional limiting applicability conditions that come into play. For example, carbon credits for peatland restoration must occur on land that was originally drained for one of the following: forestry that is no longer profitable, peat extraction that has been abandoned for at least two years prior to the project start, and/or agriculture that has been abandoned at least two years prior to the project start. The methodology also does not allow for projects on areas where commercial harvesting is considered to be part of the baseline scenario, which could be limiting for state-owned peatlands that are considered productive forestry lands. Using an existing WMA with an estimated 3,109 acres of ditched peatlands as a hypothetical example, carbon market advisors suggest that a project proponent would need to keep restoration costs below $280 per hectare (~$690/ acre) for a site of that size to be economically viable as a carbon project under current market conditions. Based on the high cost and complexity of peatland restoration in Minnesota, our initial review Natural Climate Solutions 64 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION Table 10. Sample lists of cost types associated with a peatland restoration carbon project in Minnesota. Carbon Operation and Certification Costs Project Component Stage Cost Type Feasibility Study  Feasibility Fixed Field Data  Project Design Fixed Lab Analysis  Project Design Variable Baseline Development (USD) Project Design Fixed Project Description (USD) Project Design Fixed Validation Event (VVB) Validation Fixed Registration Fee Validation Fixed Field Data Collection  Verification Fixed Monitoring Report Verification Fixed Verification Event (VVB)  Verification Fixed Issuance Levies Verification Variable Hydrology Assessment Contract Restoration Variable Permitting Fees Restoration Variable Ditch Fill Contract (Excavation Company) Restoration Variable Annual Maintenance Contract Crediting Variable TNC Safeguards & FPIC Contract Project Design Fixed Revenue Distribution Contract Verification Fixed Revenue Distribution Contract  Verification Fixed Credit Marketing & Sales Contract Project Design Fixed Outside Counsel Contract All Variable Proponent’s Staff Costs  All Variable Natural Climate Solutions 65 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION Box 5. Developing Sample Carbon Project Analysis  Phase 1: Identify eligible areas that fit with the applicability conditions of the VCS VM0036 methodology.   1. Identify parcels for further exploration, based on peatland status, ditch location, land ownership, and land use.  2. Some important applicability considerations relevant to Minnesota:  1. Must be able to avoid leakage by ensuring that there is not meaningful hydrological connectivity with nearby areas.  2. Verra methodology excludes locations that are being used for commercial forestry or agriculture, to avoid activity shifting and market leakage.   3. In Minnesota, state forest lands contain large areas of ditched peatlands, but are commercially harvested and therefore not eligible for this methodology.  Phase 2: Complete feasibility analysis on a sample location. Based on conditions determined in the phase 1 applicability analysis, the teams at TNC and TerraCarbon selected a WMA to create a hypothetical carbon project feasibility analysis. Determine Site Characteristics: 1. Estimated 3,109 acres of ditched peatlands.  2. Originally ditched for agriculture and logging. Ditches are still in place and the legacy causes continued emissions. 3. Current land use: Wildlife Management Area managed by the DNR Determine Project crediting period 1. Initial project crediting period of 20 years: 2025 to 2045. This could be renewed once, for a total crediting period of 40 years.  1. validation and verification within 5 years of the project start date 2. subsequent verifications at intervals of a maximum of 5 years Estimate expenses from similar projects and models 1. Based on estimated expenses and revenues, calculations show that this project would need to keep restoration costs below $280 per hectare (~$690/ acre) for a site of that size to be economically viable as a carbon project. Lessons Learned 1. Applicability conditions can have a large impact on eligible land (i.e. forestry designated land) 2. VM0036 carbon project methodology is evolving and possibly changeable . 3. In Minnesota, restoration is expensive. Under current conditions, peatland restoration carbon project would likely need additional funding from other sources in order to be financially viable. Natural Climate Solutions 66 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION The use of carbon financing to fund peatland restoration in Minnesota is unlikely to provide a long-term solution, nor is this appropriate or applicable for all locations and partners. However, in some cases, it may have the potential to serve as a short-term enabling factor, and to drive the kind of investments needed to develop restoration capacity in the short-term. By contrast, wetland mitigation is well established in Minnesota as a regulatory mechanism that drives wetland restoration, including some peatlands. Mitigation banks are a special type of mitigation that creates larger, high-quality restored wetlands, where organizations can buy credits for wetland impacts incurred elsewhere. Most wetland banks aren’t built on county or state-owned lands because private parties can’t use public funding or resources to profit from the sale of mitigation bank credits. However, several wetland banks originally established on private lands have been later acquired by the state as public WMAs. Government agencies are not generally exempt from mitigation requirements and must also mitigate wetland impacts. Ongoing market demand for additional wetland mitigation credits in the state of Minnesota is driven by permitted “unavoidable” impacts to benefits. Statewide, the most recent BWSR data existing wetlands, largely due to private and public layer shows more than 41,000 acres of approved road and infrastructure development. A significant wetland banks, of which more than 24,000 acres amount of literature evaluating wetland mitigation occur on soils mapped as histosols. effectiveness has raised significant and legitimate Because Minnesota wetland law requires concerns about whether replacement wetlands not just replacement of wetland acres, but are adequately compensating for lost wetland “wetland functions and services,” there is an functions and values (Burgin, 2010), including opportunity to improve accounting for carbon carbon storage. In general, mitigation wetlands functions through improved wetland mitigation have been able to restore desired water levels but approaches. State and federal wetland mitigation plant community re-establishment has been less laws, recognizing that the quality and type successful. Despite their problems, mitigation of functions and services lost are difficult to wetlands have been a driving force behind a replace and take time to recover, typically require growing portfolio of peatland restoration case replacement at ratios of 2:1 or larger (Jaschke studies dating back at least thirty years, providing and Larson, 1995), depending on wetland type opportunities for an evaluation of impacts and co- and location within Minnesota. Because this Natural Climate Solutions 67 Playbook for Minnesota Peatlands Photograph © Derek Montgomery EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION requires restoring a larger area of wetland than Sociopolitical feasibility the areas impacted, this does create the potential to address past wetland loss in terms of both In addition to the biophysical and economic extent and ecosystem services. According to the feasibility considerations, sociopolitical attitudes, law, mitigation wetlands are also supposed to values, and acceptance also impact the feasibility occur as close as possible to the lost wetlands, of peatland restoration. Across Minnesota, preferably in the same watershed, although this many public and private ditch systems are still is frequently impractical. Regardless, due to the actively maintained and are largely promoted and large lag time involved in restoring lost functions perceived as providing benefits to landowners. and services, a comprehensive peatland strategy State statute chapter 103E governs state drainage should encourage siting and/or routing of linear law, which is largely administered through infrastructure and other projects involving county drainage authorities. Public ditches construction, conversion, etc. to avoid impacts to may be maintained or excavated to reestablish peatlands whenever possible. Achieving that goal their original depth if petitioned by landowners would require effective enforcement of the WCA and/or approved by the local government unit. and implementation of the (wetland) mitigation Though attitudes and values about wetlands have hierarchy: avoid, minimize/reduce, and restore. changed considerably in the past decades, many landowners are understandably concerned about Efforts are ongoing to establish additional the potential of ditch abandonment or plugging workable mechanisms for enabling ecosystem to negatively impact their property value or affect services payments on state and county lands. This their ability to use their own land. Even though is particularly relevant for School Trust Lands that peatlands can provide downstream water storage are constitutionally obligated to generate revenue and water quality benefits, benefits do depend to the School Trust Fund according to their on factors such as location in relation to the “highest and best use.” In the case of peatlands, restoration site. In most cases where proposed this may indeed be carbon storage and climate restoration may impact downstream or adjacent mitigation. For peatlands on School Trust Lands, property owners, detailed hydrologic studies will the bulk of revenue generated is through peat be needed to ensure restoration or ditch closure harvest and other mining leases. Some forestry designs will not impact neighboring properties revenue is also derived from some of the more or increase the risk of localized flooding in productive lowland conifer stands. Ultimately, areas adjacent to the restoration site. Even with the Trust needs to be compensated for any land good studies and evidence supporting net local use designations or new protections that result benefits, a proposed restoration project may still in foregone revenue to the Trust, unless those are find it difficult to win community or neighboring decisions are based on “sound natural resource landowner support. Regardless, peatland principles.” Some climate mitigation may also be restoration projects need to be designed to avoid achieved through improved forest management impacting nearby properties, which may increase on lowland conifer forest peatlands. In particular, the design cost. As such, restoration projects thinning of dense forest cover prior to re-wetting are likely more feasible where they involve may allow for harvest of many trees that would limited ditch complexity or land ownership/ be subject to mortality following re-wetting, while administration, as well as where they provide opening up the canopy to allow for Sphagnum clear co-benefits like water quality, water storage, mosses to recover. and habitat for which there is a recognized need. Natural Climate Solutions 68 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION Though some attitudes related to drainage and management goals, statutory obligations, and ditching have changed, laws relating to drainage administrative policies and procedures, and are largely designed to facilitate maintenance of sources and mechanisms for funding or financing drainage projects. For example, under existing or restoration. Coordinating such projects across drainage laws, abandonment of public ditches is multiple administrative interests is challenging, a complex and burdensome process for drainage especially where restoration involves potential authorities (e.g. counties or watershed districts). loss of revenue or other existing benefit streams, The legal system also typically places a high but not impossible. burden of proof on individual landowners who opt out of drainage improvements or “benefits As mentioned earlier, ongoing discussions assessments,” or to pursue restoration on their between OSTL, DNR, counties, and others own properties, even in some cases on privately are exploring potential revenue streams maintained ditches. This is especially true if from ecosystem services or conservation adjacent landowners want to maintain the leases. School Trust Land managers have an drainage function of the ditch. opportunity to broaden their revenue portfolios by engaging with ecosystem service markets. A recent analysis, authored by Dovetail Partners Institutional feasibility with TNC input, identified opportunities to generate carbon revenue via “improved forest Even on public land, the complexity of ownership management” on forested School Trust Lands by and management is a consideration for potential managing for increased forest carbon storage and restoration projects. Many potential restoration sequestration in forest biomass (Fernholz et al., sites involve a complex matrix of federal, 2021). The report recommended that ecosystem county, and state lands subject to different services criteria be used to conduct a strategic Photograph © Derek Montgomery Natural Climate Solutions 69 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION assessment of School Trust Lands to identify carbon revenue, the large amount of peatland on the best and most marketable opportunities for School Trust Lands underscores the importance multiple ecosystem service payments, while of evaluating the relative cost effectiveness of acknowledging that these markets change peatland restoration as compared with other over time. Though that report was focused on NCS pathways such as IFM across the different a different NCS pathway—Improved Forest peatland types. Management (IFM)—as a means of generating Table 11. Tactics and options for a comprehensive statewide Strategy for Peatland Protection, Management, and Restoration Strategy for Peatland Protection, Management, and Restoration Strategy Applicability Tactics/Options Protect large Intact peatlands • Quantify impacts and mitigation requirements remaining standing on private lands for all new impacts to peatlands going forward stocks of carbon in (peat mining, wetland impacts, etc.) intact peatlands • Protect high quality at-risk peatlands through acquisition or easements • Support improved implementation of WCA • Expand wetland functional assessment to account for carbon functions and services • Adhere to the mitigation hierarchy (avoid/ minimize/mitigate) in reference to carbon impacts Public (federal, • Identify and promote forestry best management state, and practices (BMPs) and improved forest county lands) management (IFM) on lowland conifer/peat forestry lands to enhance carbon sequestration and/or minimize net above- and below-ground carbon loss, including reducing the risk of high- intensity peat fires • Develop public/private road/infrastructure BMPs that reduce drainage needs and carbon impacts to peatlands Natural Climate Solutions 70 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION Table 11. Cont. Re-wet partially State-owned or • Public (federal and state) funding for DNR to drained extensive administered: conduct peat habitat restoration on WMA lands peatlands in WMAs northern Minnesota School Trust • Explore carbon finance and PES mechanisms Land /State (e.g., carbon leasing through voluntary/ Forests alternative carbon markets, peatland re- wetting and IFM Old growth buyout, additional SNA designation and buyout, exchange nonproductive School Trust Land peatlands for forestry lands with IFM/reforestation potential (e.g., through Strategic Land Asset Management (SLAM)) Restore large peat/ Public • WMA acquisition to enable larger peatland/ muck wetlands wetland restoration complexes throughout central • Restoration of partially drained wetlands on Minnesota in existing WMAs and public land areas degraded by drainage, Private • BWSR RIM agriculture, or other • BWSR wetland and water storage easements activities • Federal wetland private lands programs (NRCS/ USDA WRP, USFWS) including Partners for Fish and Wildlife • Minnesota Prairie Plan wetland restoration on perennial connection lands Public or private • Identify additional peatland restoration opportunities where they provide water quality, water storage, biodiversity, or other co- benefits, especially where connected to existing programs and funding sources Natural Climate Solutions 71 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION Key Takeaways Biophysical feasibility • A number of physical, biological, and environmental factors affect the feasibility of peatland restoration. These include factors such as peatland type, restoration size, ditch properties, hydrologic complexity, level of peat degradation, time since drainage and/or maintenance, and size of the ditches. Economic feasibility: costs • Peatland restoration projects can range from relatively inexpensive options such as passive ditch abandonment to more costly interventions such as ditch plugging and active seeding of peat to ensure full restoration. • Large-scale projects are typically more economical because of fixed costs for equipment mobilization, design, and planning. • In northern Minnesota, large amounts of public land and cheaper land prices can make projects more financially feasible, as compared to southern Minnesota. Economic feasibility: funding opportunities • Carbon financing in Minnesota is in the early stages, but could play a role in funding peatland restoration projects. • Initial assessments show the largest restoration opportunity areas that meet conditions for a possible carbon project are on state-owned lands, but that based on the high cost and complexity of peatland restoration in Minnesota, most projects interested in using carbon markets to fund restoration would also need significant outside financial investments (i.e. grant funding or private philanthropy support). • Wetland mitigation is well-established in Minnesota as a regulatory mechanism that funds wetland restoration, including some peatlands. Natural Climate Solutions 72 Playbook for Minnesota Peatlands EXPLORING THE BIOPHYSICAL, ECONOMIC, AND SOCIO-POLITICAL FEASIBILITY OF PEATLAND RESTORATION Key Takeaways, continued Sociopolitical feasibility • Many landowners are understandably concerned about the potential of nearby ditch abandonment or plugging to negatively impact flooding on their property, though hydrologic studies will work to make sure that any project doesn’t have negative offsite impacts. Institutional feasibility • Many potential restoration sites involve a complex matrix of federal, county, and state lands subject to different management goals, statutory obligations, and administrative policies and procedures, and sources and mechanisms for funding or financing or restoration. Natural Climate Solutions 73 Playbook for Minnesota Peatlands SCALING PEAT INTERVENTIONS TO ACHIEVE MEASURABLE IMPACTS Photograph © Derek Montgomery Scaling peat interventions to achieve measurable impacts Peatland protection and restoration are complex valuing the climate services of peatlands relative and multi-sectoral initiatives that require ongoing to alternative revenue generating activities. communication and coordination among local The allocation of more financial resources to landowners, Tribes, state and federal agencies, peatland restoration is urgently needed because and NGOs. Globally, there is increasing the lack of adequate financial incentives for recognition that taking action to monitor, assess, sustainable peatland management remains a and restore peatland ecosystems is a point of key barrier to progress. urgency to meet global climate mitigation targets (Loisel and Gallego-Sala, 2022; UNEP, 2022). At In 2023, TNC hosted a peatland symposium in the same time, there is broad recognition that Minnesota to bring together these stakeholders, scaling peatland protection and restoration will and consequently launched a series of working require action, policy, and science at multiple groups and partner conversations to amplify scales. A policy brief produced by the Ramsar communication and knowledge, and to coordinate Convention on Wetlands (2021) recognizes toward shared restoration goals. Though these that restoring drained peatlands will be a groups are ongoing and changing, initial lessons critical part of achieving global climate goals, show that there is a lot of energy and interest but acknowledges that scaling up globally will in peatlands in Minnesota, but need for more require additional work in each unique peatland coordination among groups. As part of this context. New policies may also be needed in each coordination, it will be important to make sure jurisdiction to move from peatland degradation that interested parties are ready to propose or to peatland conservation and restoration. In implement potential projects when funding arises, Minnesota, this may include state support for including being comfortable with prioritizing re-wetting, reclamation, and restoration of sites and understanding potential restoration drained sites, and improved policy frameworks for techniques and expenses. We are continuing to Natural Climate Solutions 74 Playbook for Minnesota Peatlands SCALING PEAT INTERVENTIONS TO ACHIEVE MEASURABLE IMPACTS work with partners and collaborators to prioritize nations and Indonesia. Finland’s experience with implementation opportunities across the suite developing restoration and improved forestry of peatland types and settings in our region. management approaches for drained peatlands, In particular, we are working closely with the as well as its focus on Indigenous, locally-led Minnesota DNR, which administers the largest area and community driven restoration, is especially of peatlands statewide, to develop management relevant to Minnesota. plans in collaboration with other key partners. We are also working to support restoration on private The 2021 Ramsar policy brief also called for lands within more agricultural areas in central and “more precise measurement and reporting and southern Minnesota. more coherent documentation of biodiversity values and climate change impacts, combined Beyond Minnesota, national and international with socio-economic information” in order partnerships also provide an opportunity for to help expand policy options and cultivate sharing knowledge and resources. In North broader support from society at large. Our Carolina, TNC has helped lead development chapter’s ongoing monitoring and assessment of of an approved carbon market framework to existing restoration sites continues to improve finance restoration of “pocosin” peatlands in the our understanding of the benefits of peatland southeastern United States, and lessons from restoration. To support the chapter’s freshwater this pilot program could translate to Minnesota’s program priorities, which include targeting temperate and boreal peatland ecosystems. wetland restoration (including peatlands) for In Canada’s southern peatland extents, where multiple benefits, we are continuing to assess and peat mining operations have been far more evaluate vegetation recovery, nutrient reduction, extensive than in Minnesota, researchers have hydrologic, and carbon benefits at multiple sites, developed a “Moss Layer Transfer Technique” and to expand our partnerships and learning to successfully restore Sphagnum mosses. from other on-the-ground peatland restoration Canadian researchers have also made great and related projects. Although further work is strides in understanding peatland and wildfire required to quantify the effectiveness of peatland dynamics, and developing suggestions for restoration as climate mitigation in Minnesota, ecosystem management to prevent carbon loss we also recognize the important role these in catastrophic blazes. Due to the similarity of ecosystems play in supporting biodiversity and southern Canada’s peatland systems with those in other co-benefits. Minnesota, the Canadian experience offers many relevant insights, evaluation frameworks and research methods, research findings, and lessons learned from applied restoration that can be brought to prioritizing and scaling restoration and management here. Outside of North America, many countries are also promoting, developing, and supporting science, strategy, and policies for the restoration of drained and degraded peatlands. These include Finland, Scotland, and other northern European countries such as Germany and Estonia, and elsewhere in several Andean Natural Climate Solutions 75 Playbook for Minnesota Peatlands HEALTHY PEATLANDS BOLSTER CLIMATE CHANGE RESILIENCE, ADAPTATION, AND MITIGATION Healthy peatlands bolster climate change resilience, adaptation, and mitigation Shifts in precipitation patterns and rising This is especially important because bogs temperatures from anthropogenic climate grow vegetation very slowly compared to change may cause significant disruption of warmer, more nutrient-rich environments and peatland ecosystems, including loss of carbon therefore require long timescales to accumulate under projected warming scenarios (Hanson et significant amounts of carbon in peat. Due to al., 2020). Despite this uncertainty, peatland the slow rate of carbon sequestration, peatland protection and restoration are important protection is particularly important because conservation strategies because of the important intact peatlands contain so much of the world’s roles that healthy peatlands can play in bolstering carbon. Furthermore, intact, functioning peatlands climate change resilience and adaptation, in offer many ecosystem services that the enhance addition to mitigation. Research suggests that climate change resilience of people and nature. the current ecological condition of peatlands will For example, they provide water storage capacity, affect how they respond to climate change, and buffering against both flooding and drought that early action is important. Peatlands with (Waddington et al., 2015) and can act as fire high peat moss (Sphagnum spp.) cover are likely refugia, preventing carbon loss from wildfires to exhibit greater resilience to climate change (Harris et al., 2022; Krawchuk et al., 2016; (Alshammari et al., 2020; Glenk et al., 2014). Kuntzemann et al., 2023). Conversely, peatland areas in poor ecological condition are likely to be more vulnerable to climate change (Turetsky et al., 2015). Thus, restoration that occurs sooner rather than later to improve the health of peatlands, may be more likely to increase climate change resilience, as restored sites will have more time to recover vegetation and ecological functioning (see Swindles et al., 2019). Natural Climate Solutions 76 Playbook for Minnesota Peatlands CONCLUSION Conclusion It is clear that Natural Climate Solutions, including peatland restoration and management, are a critical strategy to address climate change. Minnesota has more peatland area than any of the lower 48 states and so peatlands play an especially important role in Minnesota’s NCS strategies. However, many of Minnesota’s peatlands have been altered by drainage and/or agriculture, causing significant GHG emissions and loss of stored carbon. Through re-wetting and restoring affected peatlands and protecting intact peatlands, we can reduce or even reverse the loss of stored carbon. Though the science of wetlands’ role in climate change mitigation is fairly new, recent studies have taught us many lessons, and evidence suggests that the restoration and protection of peatlands has strong climate mitigation potential. This has led to the creation of TNC’s peatland strategy: protect large standing carbon stocks, re-wet partially drained peatlands, and restore fully drained peat wetlands for multiple benefits. TNC has found significant climate mitigation potential in Minnesota’s peatlands, particularly on publicly-owned land, presenting a strong opportunity to scale up peatland protection and restoration with unprecedented levels of interest and funding in the state. Although some scientific uncertainties around the magnitude of peatland restoration benefits still exist, we need to act now to capitalize on the opportunities. TNC is actively engaged in researching the climate impacts of Minnesota’s peatlands and bringing together partners and stakeholders to capitalize on the current momentum. This playbook provides a resource for identifying opportunities and addressing some of the key challenges and next steps to move the ball forward on scaling up peatland protection and restoration as a key part of Minnesota’s NCS strategy. Natural Climate Solutions 77 Playbook for Minnesota Peatlands CONCLUSION Funding Acknowledgement This project was made possible by a major gift from the Bezos Earth Fund to The Nature Conservancy to support development and implementation of on-the-ground peatland NCS prototypes with the greatest potential for climate mitigation. This funding enabled us to expand our work to assess the greenhouse gas mitigation potential and feasibility of strategically scaling up peatland restoration in Minnesota, as well as to develop new partnerships, demonstration projects, and explore cost-effective financing for climate mitigation in peatlands. Acronyms BMP–Best management practices BWSR–Board of Water and Soil Resources. The Minnesota soil and water conservation agency, which works to improve and protect soil and water resources primarily on private lands. They administer state wetland programs. DOC–Dissolved Organic Carbon. The carbon content of dissolved organic matter, which is the smallest size of organic particle present in water. EF–Emissions factor. An estimate of the greenhouse gas (GHG) emissions produced by an activity or land use type. For land use, emissions factors are given in GHG emissions (often CO2 equivalents) per unit land area. GEST–Greenhouse gas Emission Site Type. Plant community type used in conjunction with water levels to estimate GHG emissions factors. System published in Couwenberg et al., 2011. GHG–Greenhouse Gas. Gases that trap heat and contribute to climate change when present in the atmosphere. In peatlands, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) are the three most common GHGs. IPCC–Intergovernmental Panel on Climate Change. International organization of governments that provides climate-related scientific information to assist with climate policy. This group creates regular climate assessment reports. (MN) DNR–(Minnesota) Department of Natural Resources. Minnesota state agency responsible for managing the state’s natural lands and waters. MMT–Million metric tons. 1 billion kilograms. MPCA–Minnesota Pollution Control Agency. Minnesota state agency responsible for regulating and Natural Climate Solutions 78 Playbook for Minnesota Peatlands CONCLUSION preventing pollution and climate change impacts. N2O–Nitrous oxide. An important GHG. It is found in low concentrations in the atmosphere, but is highly efficient at trapping heat. NASIS–National Soil Information System. Information system for entering and storing soils information for the National Cooperative Soil Survey. NCS–Natural Climate Solutions. Strategies for management of natural and working lands to decrease GHG emissions or increase GHG sequestration. NCS include three levels of action: protect, manage, and restore. NLCD–National Land Cover Database. National database describing land cover characteristics including land use type, tree cover, and impervious surface cover. NWI–National Wetland Inventory. National database of the locations and types of wetlands using the Cowardin classification system. PADUS–Protected Areas Database of the United States. National database of lands protected for conservation, recreation, or other uses. SNA–Scientific and Natural Areas. This is a class of land managed by the Minnesota Department of Natural Resources to minimize disturbance and protect scientifically or educationally valuable natural features. SOC–Soil Organic Carbon. The fraction of carbon in soils derived from living and dead and decomposed organisms. Peat soils have high SOC content, which can exceed 50%. SOCCR2–State of the Carbon Cycle Report version 2. This report provides a comprehensive assessment of the current science of the carbon cycle in North America and feedbacks with climate change. SSURGO–Soil Survey Geographic Database. National database of soil classification and soil property data produced and managed by the Natural Resource Conservation Service. STL–School Trust Lands. A class of state-owned land originally granted by the federal government and managed to generate long-term economic return to fund K-12 education. Minnesota has 2.5 million acres of School Trust Lands, which generate income primarily through iron mining and timber harvest, as well as aggregate and peat mining, mineral leases, land sales, and licensing utility crossings. STATSGO–State Soil Geographic dataset. National soil database, which offers more coverage but less detailed information than SSURGO. USDA-NRCS–United States Department of Agriculture Natural Resources Conservation Service. As the land conservation agency of the USDA, the NRCS works with partners and landowners to implement Natural Climate Solutions 79 Playbook for Minnesota Peatlands CONCLUSION management practices that promote healthy soil and water. The NRCS also leads the soil survey. USFWS–United States Fish and Wildlife Service. Federal agency tasked with protecting fish, wildlife, plants, and their habitat. WCA–Wetland Conservation Act. State statute promoting the conservation of Minnesota’s wetlands. A key piece is the requirement for no net loss of wetland area or quality. WMA–Wildlife Management Area. State lands managed to provide wildlife habitat, focused on management for hunting, fishing, and trapping. Natural Climate Solutions 80 Playbook for Minnesota Peatlands CONCLUSION References Abdalla, M., Hastings, A., Truu, J., Espenberg, M., Mander, Ü., Smith, P., 2016. Emissions of methane from northern peatlands: a review of management impacts and implications for future management options. 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Journal of Ecology Natural Climate Solutions 85 Playbook for Minnesota Peatlands CONCLUSION 103, 925–934. Rochefort, L., 2000. Sphagnum—a keystone genus in habitat restoration. The Bryologist 103, 503–508. Roe, S., Streck, C., Obersteiner, M., Frank, S., Griscom, B., Drouet, L., Fricko, O., Gusti, M., Harris, N., Hasegawa, T., Hausfather, Z., Havlík, P., House, J., Nabuurs, G.J., Popp, A., Sánchez, M.J.S., Sanderman, J., Smith, P., Stehfest, E., Lawrence, D., 2019. Contribution of the land sector to a 1.5 °C world. Nature Climate Change 9, 817–828. https://doi.org/10.1038/s41558-019-0591-9 Roulet, N.T., Lafleur, P.M., Richard, P.J., Moore, T.R., Humphreys, E.R., Bubier, J., 2007. Contemporary carbon balance and late Holocene carbon accumulation in a northern peatland. Global Change Biology 13, 397–411. Rydin, H., Jeglum, J.K., Bennett, K.D., 2013. The biology of peatlands, 2e. OUP Oxford. Shaw, S.P., Fredine, C.G., 1956. Wetlands of the United States. 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Turetsky, M.R., Benscoter, B., Page, S., Rein, G., Van Der Werf, G.R., Watts, A., 2015. Global vulnerability of peatlands to fire and carbon loss. Nature Geoscience 8, 11–14. Turetsky, M.R., Kane, E.S., Harden, J.W., Ottmar, R.D., Manies, K.L., Hoy, E., Kasischke, E.S., 2011. Recent acceleration of biomass burning and carbon losses in Alaskan forests and peatlands. Nature Geoscience 4, 27–31. Turetsky, M.R., Kotowska, A., Bubier, J., Dise, N.B., Crill, P., Hornibrook, E.R.C., Minkkinen, K., Moore, T.R., Myers-Smith, I.H., Nykänen, H., Olefeldt, D., Rinne, J., Saarnio, S., Shurpali, N., Tuittila, E.-S., Waddington, J.M., White, J.R., Wickland, K.P., Wilmking, M., 2014. A synthesis of methane emissions from 71 northern, temperate, and subtropical wetlands. Glob Change Biol 20, 2183–2197. https://doi.org/10.1111/gcb.12580 UNEP, 2022. Global Peatlands Assessment: The State of the World’s Peatlands - Main report (Main Report). Global Peatlands Initiative. 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Mires and Peat 1–28. https://doi.org/10.19189/MaP.2016.OMB.222 Zhang, H., Tuittila, E.-S., Korrensalo, A., Laine, A.M., Uljas, S., Welti, N., Kerttula, J., Maljanen, M., Elliott, D., Vesala, T., others, 2021. Methane production and oxidation potentials along a fen-bog gradient from southern boreal to subarctic peatlands in Finland. Global Change Biology 27, 4449–4464. Natural Climate Solutions 87 Playbook for Minnesota Peatlands Questions? Collaboration? Get in touch with us at minnesota@tnc.org or visit nature.org/minnesota The Nature Conservancy is a global conservation organization dedicated to conserving the lands and waters on which all life depends. Guided by science, we create innovative, on-the-ground solutions to our world’s toughest challenges so that nature and people can thrive together. We are tackling climate change, conserving lands, waters and oceans at an unprecedented scale, providing food and water sustainably and helping make cities more sustainable. The Nature Conservancy is working to make a lasting difference around the world in 81 countries and territories (40 by direct conservation impact and 41 through partners) through a collaborative approach that engages local communities, governments, the private sector, and other partners. Natural Climate Solutions 88 Playbook for Minnesota Peatlands or an executive summaryExecutive Summary Playbook for Minnesota Peatlands Protecting & Restoring Minnesota’s Peatlands as a Natural Climate Solution EXECUTIVE SUMMARY Photograph © Derek Montgomery Introduction peatlands, causing degradation of the peat and leading to net greenhouse gas emissions from these landscapes. Natural ecosystems are key to the climate and carbon cycle. They have a critical role to play Restoration, conservation, and land in achieving climate mitigation goals in the management activities can increase carbon short-term (i.e., by 2050). This is especially true storage and reduce carbon/greenhouse gas of peatlands, a type of carbon-rich wetland emissions (GHG) from peatlands to help mitigate ecosystem estimated to store more than 30% global average temperature rise. of the world’s terrestrial soil carbon while occupying just 3% of the land surface. Most Given the critical role that protecting and of this carbon is stored below ground in deep, restoring peatlands plays in the global carbon organic-matter-rich peat soil layers. cycle, The Nature Conservancy (TNC) of Minnesota, North Dakota, and South Dakota is With at least 6 million acres, Minnesota working with partners to develop a strategy to contains more peatlands than any other of the protect and restore peatlands in Minnesota as contiguous 48 United States. Peatlands cover an important component of an overall climate more than 10% of the state by area and the top change mitigation strategy. 1 meter of soil alone accounts for at least 40% of Minnesota’s stored soil carbon. Background: Minnesota’s However, historical drainage and conversion of peatlands peatlands to cropland and other land uses has disturbed the carbon balance of Minnesota’s Peat is partially decayed plant material that peatlands, converting them in many cases from accumulates in soil under moist and often cool a long-term sink to a source of atmospheric climates, where waterlogged conditions prevent carbon. Largescale ditching efforts over the microbes from breaking down dead plant past 100 years have lowered water levels in material and leaves. In the process, the carbon Natural Climate Solutions 2 Playbook for Minnesota Peatlands EXECUTIVE SUMMARY dioxide (CO2) that plants remove from the “productive” agriculture and forestry uses. In atmosphere becomes sequestered underground support of this project, the federal government so long as waterlogged conditions are passed a series of Swamp Acts starting in the maintained. While all peatlands are wetlands, 19th century to encourage draining wetlands not all wetlands are peatlands. A peatland is throughout the Great Lakes States (Dahl and typically defined as a wetland that accumulates Allord, 1996). peat, or partially decayed plant matter. Peatlands are also generally referred to as fens, State and local governments in Minnesota bogs, and swamps, though peatland definitions took up the charge in earnest throughout can vary widely (Lourenco et al., 2022). the early 1900s, dredging long trenches and using explosives to drain millions of acres of Minnesota’s peatlands predominantly developed wetlands. While not everyone supported these over the past 6,000–8,000 years, when cool, wet large-scale drainage efforts, as much as 90% climate periods combined with poor drainage in of historic wetlands in southern and western the depressions left behind by Ice Age glaciers Minnesota were drained. Drainage in northern combined to create conditions favorable to peatlands was less economically successful and peat formation. Until the late 19th century, less extensive, but ditching still contributes to much of the region’s landscape was dominated significant peatland degradation today. by wetlands of various types including bogs, fens, marshes, swamps, and wet prairies. Today, based on publicly available geographic Indigenous people valued the peatlands as data layers, we estimated that more than 41,000 intact ecosystems that furnished them with miles of streams in Minnesota have been altered food, medicines, furs, and other necessities. or modified in some way. Of this, at least 7,000 However, when European settlers moved miles directly intersect areas with peat soils. into the landscape, they viewed these poorly Restoring peatland hydrology in those areas has drained areas as wastelands, and made massive the potential to generate both climate benefits drainage investments to make land available for and restore more natural waterways. Natural Climate Solutions 3 Playbook for Minnesota Peatlands EXECUTIVE SUMMARY Peatland Drainage and Carbon or burning 154,773,500 pounds of coal. Peatland ecology is largely shaped by Some estimates in the literature suggest that hydrology—the patterns governing water quality, re-wetting peat could potentially save even water chemistry, water flow, and water table more carbon per year. Re-wetting drained dynamics. Disrupting these dynamics has peatlands may also provide additional carbon had profound impacts on peat accumulation, sequestration benefits. landforms, vegetation, and carbon. As shown in Figure 1, ditches dug through peatlands lower Given the critical importance of Minnesota’s the water table, exposing previously saturated extensive peatlands, The Nature Conservancy in peat layers to air, which accelerates oxidation MN, ND, SD is actively working to develop, refine (decomposition) of organic matter and the and implement a comprehensive 3-pronged release of CO2 and other greenhouse gases to peatland strategy: the atmosphere (Krause et al., 2021). 1. Protect carbon stocks remaining in intact peatlands Although many of these ditches are no 2. Re-wet partially drained peatlands to avoid longer actively used to support agriculture or additional carbon loss and restore the forestry, they continue to drain water out of carbon sink peatlands. If left unrestored, they will continue to contribute to peatland degradation. 3. Restore fully drained peat wetlands based on potential for multiple benefits. Ongoing carbon stock losses from partially drained peatlands in Minnesota have been This “Playbook”, developed over the past 4 years estimated at ~38,000 metric tons (MT) per year represents the first iteration of our analysis of (Krause et al., 2021), equivalent to adding about opportunities and feasibility. 32,500 gasoline powered vehicles to the roads, Carbon Cycle In Intact vs. Drained Peatlands Figure 1. Intact peatlands are net sinks for carbon. By lowering the water table, drainage allows Carbon stored in the peat to be exposed to air. This ultimately leads to increased CO2 emissions while having variable impacts on methane (CH4) production. Natural Climate Solutions 4 Playbook for Minnesota Peatlands EXECUTIVE SUMMARY Quantifying the benefits of and exploring opportunities for peatland restoration Although peatlands can be identified, mapped, and/or classified by a variety of attributes (soil types, plant communities, hydrogeomorphic wetland categories, etc.), a single complete statewide coverage map of drained and remaining peatlands did not exist prior to this project. To map physical and biological characteristics of peatlands, we compiled publicly available geospatial data layers such as soil properties, topography, wetland inventories, historical and current vegetation, existing and potential native plant communities. To assess drainage impacts, we used public data layers identifying altered watercourses and public ditches, and assessed where peat soils are most likely being impacted by drainage ditches and Land ownership and other hydrologic alterations. Combining land administration cover with ownership data, we mapped and summarized the extent of intact, drained, and Of the 7.8 million acres of land identified as partially-drained peat area by major ownership having peat soils, roughly 4.5 million (about 60%) and administrative categories. are in public ownership. To view a web-based tool developed The majority of these peatland areas are state- concurrently by the Minnesota Board of Water owned, particularly in northern Minnesota. They and Soil Resources (BWSR), using many of these are managed under a variety of different state same data layers, see the Potentially Restorable administrative and surface interest categories, Peatlands Mapping Tool http://bit.ly/4hyum8Q. depending on how they were acquired and for what purposes they have most recently We also interpreted soil data layers to estimate been designated. These varied designations peatland carbon stocks by ownership, peatland and management interests have important type, and drainage conditions. We then implications for strategy and opportunities for combined estimates of drained and partially- carbon management. drained peatland extent with estimates of avoided carbon stock loss and carbon Of these state-owned or administered lands, sequestration rates derived from the literature the areas with the highest acreage on peat soils to estimate the potential climate mitigation include State Forest lands, School Trust lands, impacts associated with different peatland Consolidated Conservation lands, and Wildlife protection and restoration strategies. Management Areas. Natural Climate Solutions 5 Playbook for Minnesota Peatlands Photograph © Mark Godfrey EXECUTIVE SUMMARY Drained peatlands in private Re-wetting of partially-drained northern ownership temperate peatlands represents a significant natural climate solution (NCS) pathway More that 3 million acres with peat soils are in Minnesota due to the presence of high in private ownership across the state, with remaining carbon stocks, the ongoing threat many of those acres drained and converted for of degradation from legacy drainage, and net agriculture or other uses. In its 2018 statewide positive greenhouse gas dynamics of restoring inventory, Minnesota Pollution Control Agency ditched peat. (MPCA) estimated emissions from fully drained peat soils as the fourth highest source of emissions, just after light trucks. Using updated Feasibility and Scaling Up land cover layers intersected with the histosol layer, we estimated approximately 475,000 Many factors affect the feasibility of peatland acres of peat soils in cropland or pasture. restoration, including ecological type, biophysical and landscape setting, technical Climate Change Mitigation complexity, and social, economic, institutional, Potential and governance practices. Biophysical factors affecting the feasibility Academic literature confirms a strong link of peatland restoration include vegetation, between re-wetting drained peatlands and hydrology, chemistry, restoration size, ditch increasing the water table to long-term properties, hydrologic complexity, level of reductions in CO2 emissions, but also a short- peat degradation, time since drainage and/or term increase in methane (CH4) emissions. maintenance, and size of the ditches. These Estimating which has a stronger impact can be factors can also affect costs and economic difficult because of variation in carbon fluxes feasibility. with time and across landscapes. However, general evidence indicates the long-term Peatland restoration projects can range benefits of CO2 reduction outweigh the short- from relatively inexpensive options, such as term impacts from CH4 emission and that passive ditch abandonment, to more costly re-wetting peatlands will result in a net carbon interventions such as ditch plugging and active sink. seeding of peat to ensure full restoration. Cost and feasibility are also affected by land Based on updated estimates of the extent of values, opportunity cost, and impacts to histosol soils and other high carbon stock soil adjacent properties, both real and perceived. types statewide, we estimated the climate Large-scale projects are typically considered mitigation potential for restoration of farmed more economical because of fixed costs for peatlands at nearly 582,000 Mt CO2e per year. equipment mobilization, design, and planning. For partially-drained peat impacted by altered However, they may also may involve ecological drainage channels, we estimate the total complexity and social complexity (e.g. more statewide potential climate mitigation benefits landowners impacted). of restoration at more than 500,000 Mt of carbon per year. Restoration and re-wetting on A majority of funding for peatland restoration is public land alone would be 282,000 Mt. currently provided through federal, state, and Natural Climate Solutions 6 Playbook for Minnesota Peatlands EXECUTIVE SUMMARY Photograph © Derek Montgomery local sources. At the federal level, the Inflation Reduction Act has provided some opportunities Carbon financing in Minnesota is in the for securing funding for peatland restoration. early stages, but could also play a role in funding peatland restoration projects. Initial At the state level, support includes funding for assessments show the largest restoration a Department of Natural Resources (DNR) pilot opportunity areas are on state-owned lands, restoration program, a state Legislative-Citizen but that based on the high cost and complexity Commission on Minnesota Resources (LCCMR) of peatland restoration in Minnesota, most grant awarded to the University of Minnesota projects interested in using carbon finance to for research on northern peatlands, and the fund restoration would also need significant Minnesota Board of Water and Soil Resources outside financial investments (i.e. grant funding (BWSR) new Reinvest in Minnesota (RIM) or private philanthropic support). program for peatland restoration on private lands. There is also an opportunity to move Institutional and sociopolitical feasibility factors support for peatland protection and restoration are also critically important to consider in forward through the state’s Climate Action peatland restoration. Many potential restoration Framework. Additionally, wetland mitigation is sites involve a complex matrix of federal, well-established in Minnesota as a regulatory county, and state lands subject to different mechanism that funds wetland restoration, management goals, statutory obligations, including some peatlands. administrative policies, and sources and mechanisms for funding or financing for There is also significant opportunity to engage restoration. Because drainage has long been directly on potential ditch abandonment viewed in much of Minnesota as essential for projects with county drainage authorities economic development of land, restoration seeking to reduce the long-term maintenance often represents a major cultural shift in burden of public drainage systems on taxpayers, thinking about the value of wetland ecosystems. local, and state government. Landowners and communities will need Natural Climate Solutions 7 Playbook for Minnesota Peatlands EXECUTIVE SUMMARY assurances that projects will not negatively play as part of Minnesota’s portfolio of NCS impact their own lands or property values, that strategies. By protecting intact peatlands, as the changes will result in net benefits, and/or well as re-wetting and restoring drained and that benefits and costs will be fairly distributed. degraded peatlands, we can protect existing stocks and reduce or even reverse the loss of Conclusion stored carbon by restoring peatlands. Though the potential role of wetlands in climate change As the largest natural terrestrial carbon storage mitigation is complex, evidence continues to ecosystem, peatlands represent a critical suggest that the restoration and protection of component of Natural Climate Solutions needed peatlands has a critical role to play in climate to reduce atmospheric carbon emissions and mitigation. achieve climate mitigation goals. Minnesota has more peatland area and carbon stocks than any of the other lower 48 Read the full report: states. However, legacy effects of historic nature.org/mnpeatlands drainage combined with climate changes already underway represent a major threat to Minnesota’s remaining peatland carbon stocks; therefore, peatlands have an outsize role to Photograph © Derek Montgomery Natural Climate Solutions 8 Playbook for Minnesota Peatlands Questions? Collaboration? Get in touch with us at minnesota@tnc.org or visit nature.org/minnesota The Nature Conservancy is a global conservation organization dedicated to conserving the lands and waters on which all life depends. Guided by science, we create innovative, on-the-ground solutions to our world’s toughest challenges so that nature and people can thrive together. We are tackling climate change, conserving lands, waters and oceans at an unprecedented scale, providing food and water sustainably and helping make cities more sustainable. The Nature Conservancy is working to make a lasting difference around the world in 81 countries and territories (40 by direct conservation impact and 41 through partners) through a collaborative approach that engages local communities, governments, the private sector, and other partners. Natural Climate Solutions 9 Playbook for Minnesota Peatlands.