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Draining peatlands to create agricultural land has been the norm in Europe, but in the context of climate change and the loss of biodiversity, these rich ecosystems may reactivate their functions as greenhouse gas sinks and retreat spaces for animals and plants. Against this background, the National Moor Rewetting Strategy was put into effect in Germany in 2023, together with the Natural Climate Protection Action Plan. This article examines the methodology of peatland rewetting from scientific, administrative, social, and technical perspectives. The article focuses on an example of moor rewetting in central Germany: the Rathsbruch moor near the municipality of Zerbst, Saxony-Anhalt. To illustrate the importance of rewetting projects for degraded peatlands, five scenarios with different target soil water levels were considered, and the associated greenhouse gas emissions were calculated for a period of five years. For the planning solution, an estimate of the medium-to-long-term development of the habitat types was made based on current use and the dynamics typical of the habitat. The results for the Rathsbruch moor area showed that increasing the water level in steps of 1, 0.8, or 0.5 m has no significant influence on reducing the CO2 emissions situation, while a depth of 0.3 m has a slight influence. When the water was raised to 0.1 m below the surface (Scenario 5), a significant CO2 reduction was observed. The calculated avoided CO2 costs due to environmental damage show that the environmental benefits multiply with every decimeter of water level increase. The rising groundwater levels and extensification favor the establishment of local biotopes. This means that two of the biggest man-made problems (extinction of species and climate change) can be reduced. Therefore, this research is applicable to the development and planning of recultivation work at municipal and regional levels in Germany and beyond within the framework of EU restoration policy. [ABSTRACT FROM AUTHOR]

Restoration of drained peatlands through rewetting has recently emerged as a prevailing strategy to mitigate excessive greenhouse gas emissions and re-establish the vital carbon sequestration capacity of peatlands. Rewetting can help to restore vegetation communities and biodiversity, while still allowing for extensive agricultural management such as paludiculture. Belowground processes governing carbon fluxes and greenhouse gas dynamics are mediated by a complex network of microbial communities and processes. Our understanding of this complexity and its multi-factorial controls in rewetted peatlands is limited. Here, we summarize the research regarding the role of soil microbial communities and functions in driving carbon and nutrient cycling in rewetted peatlands including the use of molecular biology techniques in understanding biogeochemical processes linked to greenhouse gas fluxes. We emphasize that rapidly advancing molecular biology approaches, such as high-throughput sequencing, are powerful tools helping to elucidate the dynamics of key biogeochemical processes when combined with isotope tracing and greenhouse gas measuring techniques. Insights gained from the gathered studies can help inform efficient monitoring practices for rewetted peatlands and the development of climate-smart restoration and management strategies. [ABSTRACT FROM AUTHOR]

In recent years, research on carbon dioxide removal (CDR) has significantly increased. Numerous studies have analyzed demonstration projects, outlined scenarios, modeled pathways, or focused on CDR's national or international governance. However, regional case studies investigating the dynamics that may facilitate or impede the broader adoption of CDR methods in spatially explicit settings are critically absent. Understanding implementation contexts on the ground is vital, and comparing them across different removal methods is essential for effectively scaling up CDR. This paper aims to address this research gap by comparatively examining the development of biomass-based CDR in three regions of Germany. Taking an exploratory approach, we conducted surveys in these regions to gain insight into stakeholder perceptions of the following six CDR methods: forest management, agriculture and soil carbon, long-lasting building materials, rewetting of peatlands and paludiculture, biochar, and bioenergy with carbon capture and storage. In this article, we present the results of the stakeholder survey, which offers multiple perspectives that can shape future studies of regional implementation and yield policy-relevant guidance. Although our research primarily focuses on the regional level in Germany, it sheds light on various conflicts, uncertainties, and potentials that are likely to be relevant for the rollout of CDR in other countries. By examining these aspects, we contribute to the broader discourse on CDR and its potential implementation. [ABSTRACT FROM AUTHOR]

Draining peatlands to create agricultural land has been the norm in Europe, but in the context of climate change and the loss of biodiversity, these rich ecosystems may reactivate their functions as greenhouse gas sinks and retreat spaces for animals and plants. Against this background, the National Moor Rewetting Strategy was put into effect in Germany in 2023, together with the Natural Climate Protection Action Plan. This article examines the methodology of peatland rewetting from scientific, administrative, social, and technical perspectives. The article focuses on an example of moor rewetting in central Germany: the Rathsbruch moor near the municipality of Zerbst, Saxony-Anhalt. To illustrate the importance of rewetting projects for degraded peatlands, five scenarios with different target soil water levels were considered, and the associated greenhouse gas emissions were calculated for a period of five years. For the planning solution, an estimate of the medium-to-long-term development of the habitat types was made based on current use and the dynamics typical of the habitat. The results for the Rathsbruch moor area showed that increasing the water level in steps of 1, 0.8, or 0.5 m has no significant influence on reducing the CO2 emissions situation, while a depth of 0.3 m has a slight influence. When the water was raised to 0.1 m below the surface (Scenario 5), a significant CO2 reduction was observed. The calculated avoided CO2 costs due to environmental damage show that the environmental benefits multiply with every decimeter of water level increase. The rising groundwater levels and extensification favor the establishment of local biotopes. This means that two of the biggest man-made problems (extinction of species and climate change) can be reduced. Therefore, this research is applicable to the development and planning of recultivation work at municipal and regional levels in Germany and beyond within the framework of EU restoration policy.

In recent years, research on carbon dioxide removal (CDR) has significantly increased. Numerous studies have analyzed demonstration projects, outlined scenarios, modeled pathways, or focused on CDR’s national or international governance. However, regional case studies investigating the dynamics that may facilitate or impede the broader adoption of CDR methods in spatially explicit settings are critically absent. Understanding implementation contexts on the ground is vital, and comparing them across different removal methods is essential for effectively scaling up CDR. This paper aims to address this research gap by comparatively examining the development of biomass-based CDR in three regions of Germany. Taking an exploratory approach, we conducted surveys in these regions to gain insight into stakeholder perceptions of the following six CDR methods: forest management, agriculture and soil carbon, long-lasting building materials, rewetting of peatlands and paludiculture, biochar, and bioenergy with carbon capture and storage. In this article, we present the results of the stakeholder survey, which offers multiple perspectives that can shape future studies of regional implementation and yield policy-relevant guidance. Although our research primarily focuses on the regional level in Germany, it sheds light on various conflicts, uncertainties, and potentials that are likely to be relevant for the rollout of CDR in other countries. By examining these aspects, we contribute to the broader discourse on CDR and its potential implementation.

Drainage and agricultural use transform natural peatlands from a net carbon (C) sink to a net C source. Rewetting of peatlands, despite of high methane (CH4) emissions, holds the potential to mitigate climate change by greatly reducing CO2 emissions. However, the time span for this transition is unknown because most studies are limited to a few years. Especially, nonpermanent open water areas often created after rewetting, are highly productive. Here, we present 14 consecutive years of CH4 flux measurements following rewetting of a formerly long‐term drained peatland in the Peene valley. Measurements were made at two rewetted sites (non‐inundated vs. inundated) using manual chambers. During the study period, significant differences in measured CH4 emissions occurred. In general, these differences overlapped with stages of ecosystem transition from a cultivated grassland to a polytrophic lake dominated by emergent helophytes, but could also be additionally explained by other variables. This transition started with a rapid vegetation shift from dying cultivated grasses to open water floating and submerged hydrophytes and significantly increased CH4 emissions. Since 2008, helophytes have gradually spread from the shoreline into the open water area, especially in drier years. This process was periodically delayed by exceptional inundation and eventually resulted in the inundated site being covered by emergent helophytes. While the period between 2009 and 2015 showed exceptionally high CH4 emissions, these decreased significantly after cattail and other emergent helophytes became dominant at the inundated site. Therefore, CH4 emissions declined only after 10 years of transition following rewetting, potentially reaching a new steady state. Overall, this study highlights the importance of an integrative approach to understand the shallow lakes CH4 biogeochemistry, encompassing the entire area with its mosaic of different vegetation forms. This should be ideally done through a study design including proper measurement site allocation as well as long‐term measurements. [ABSTRACT FROM AUTHOR]

Background: Recurring wildfires on degraded peatlands throughout Central Kalimantan have resulted in severe economic and social impacts for local people along with globally significant environmental impacts. The interdependence between the livelihoods of local villagers and wildfire is not well understood in areas of degraded peat in proximity to urban environments. Aims: The aim of the study was to consider fire hotspots in two villages close to the regional capital of Palangka Raya. These were Kalampangan, a Javanese transmigrant farming village, and Tumbang Nusa, a Dayaknese fishing village. Methods: A system dynamics model was constructed to study the factors contributing to greenhouse gas emissions and wildfire extent resulting from long-term peatland degradation. The model was used to analyse existing policy scenarios where degraded peatlands are cultivated in perpetuity, and then consider hypothetical future policy scenarios where efforts are made to rewet and rehabilitate peatland while alternative livelihoods are enabled. Conclusions: Analysis reveals that the assumption within the model of unconstrained alternative livelihoods is insufficient to facilitate full rewetting where the incumbent livelihood is reliant on drained peatland. Implications: Only when livelihood alternatives displace drained peatland cultivation is full rewetting and sustained reduction in fire risk achievable in both villages. Significant greenhouse gas (GHG) emissions reductions were only achieved with full rewetting. Unconstrained availability of livelihood alternatives will not lead to full rewetting where drained peatland cultivation supports the incumbent livelihood. Livelihood alternatives displacing drained peatland cultivation are essential for sustained reduction in fire risk and GHG emissions. [ABSTRACT FROM AUTHOR]

Peat forest plays a principal role in climate change mitigation in Indonesia. Considering the potential releases of GHGs from a forest fire and degraded peatland, it is important to conserve peatland forests. Besides being essential for ecological balancing, the role of peatland forest expands to the economic and social aspects. The purpose of this research was to calculate CO2 emissions that can be avoided by the community-based fire prevention and rewetting program. This research utilized spatial analysis to calculated avoided CO2 emissions in six villages in Central Kalimantan. Data and information for the calculation were generated from field observations, interviews, and desk study. Spatial analysis using Arc GIS 10.5 was applied to compute the incombustible areas. The result from the analysis found that fire prevention and rewetting programs managed to prevent approximately 1 million Mg C or equivalent to 3.7 million CO2. The program managed to prevent emission from the vulnerable area including swamp shrubs, plantations and dry land agriculture. The finding of this study suggests that community-based fire prevention and peatland rewetting programs could become a strategic program in climate change mitigation in Indonesia. Keywords: climate change mitigation, fire prevention, peatland rewetting, community based program, avoided CO2

Peat fires differ from other wildfires by significant carbon loss, the emission of greenhouse gases and other combustion products as well as by serious environmental consequences. Not only biomass but also peat is burnt. A possibility of detecting peat fires from satellite and ground-based data is considered for the fires in the Moscow region in 2010. The peat fire detection technique was tested by superimposing data on thermal anomalies from Terra/Aqua MODIS satellite data on the peatland contours, as well as by analyzing the vegetation cover changes before fires and the next year using the Landsat satellite multispectral data. Threshold values were found for the fire duration, maximum temperature, and maximum fire radiative power that characterize peat fires and can be used to discriminate between fires on peat lands and peat fires themselves for taking into account emissions not only from biomass burning but also from soil carbon loss. [ABSTRACT FROM AUTHOR]

Effects of restoration management on peatlands formerly used for intensive agriculture are rarely evaluated or discussed over larger spatial and temporal scales. Here, restoration of the Drentsche Aa brook valley was evaluated at the landscape level. Detailed vegetation maps were used with 1982 serving as the baseline, 1994 representing vegetation before rewetting, and 2015 after rewetting. Based on the mapping typology and phytosociological records, 15 main vegetation types were distinguished. Species richness and Shannon index values were calculated as plant diversity indicators, and the number of rare species was used as a rarity indicator. Basic landscape metrics were evaluated as measures of spatial heterogeneity. Results after restoration measures showed extensive vegetation type conversions clearly pointed to lower nutrient levels, and an increase in marsh vegetation at the cost of wet meadows. Significantly higher landscape heterogeneity was achieved, while biodiversity indicators showed small differences over time due to a mixture of positive and negative changes at different locations. This study shows that long‐term restoration management on agricultural peatlands can be successful at landscape level. Our experience highlights the importance of continuity in management given the prolonged influence by intensive agriculture, both from former land uses and from the surrounding valley flanks. [ABSTRACT FROM AUTHOR]

Peat forest plays a principal role in climate change mitigation in Indonesia. Considering the potential releases of GHGs from a forest fire and degraded peatland, it is important to conserve peatland forests. Besides being essential for ecological balancing, the role of peatland forest expands to the economic and social aspects. The purpose of this research was to calculate CO2 emissions that can be avoided by the community-based fire prevention and rewetting program. This research utilized spatial analysis to calculated avoided CO2 emissions in six villages in Central Kalimantan. Data and information for the calculation were generated from field observations, interviews, and desk study. Spatial analysis using Arc GIS 10.5 was applied to compute the incombustible areas. The result from the analysis found that fire prevention and rewetting programs managed to prevent approximately 1 million Mg C or equivalent to 3.7 million CO2. The program managed to prevent emission from the vulnerable area including swamp shrubs, plantations and dry land agriculture. The finding of this study suggests that community-based fire prevention and peatland rewetting programs could become a strategic program in climate change mitigation in Indonesia. [ABSTRACT FROM AUTHOR]

Increased agricultural use of tropical peatlands has negative environmental effects. Drainage leads to landscape-wide degradation and fire risks. Livelihood strategies in peatland ecosystems have traditionally focused on transitions from riverbanks to peatland forests. Riparian 'Kaleka' agroforests with more than 100 years of history persist in the peatlands of Central Kalimantan (Indonesia), where large-scale open-field agricultural projects have dramatically failed. Our field study in a Dayak Ngaju village on the Kahayan river in the Pulang Pisau district involved characterizing land uses, surveying vegetation, measuring soil characteristics, and monitoring groundwater during a period of 16 months. We focused on how local practices and farmer knowledge compare with standard soil fertility (physical, chemical, biological) measurements to make meaningful assessments of risks and opportunities for sustainable land use within site-specific constraints. The Kaleka agroforests around a former settlement and sacred historical meaning are species-rich agroforests dominated by local fruit trees and rubber close to the riverbank. They function well with high wet-season groundwater tables (up to -- 15 cm) compatible with peatland restoration targets. Existing soil quality indices rate the soils, with low soil pH and high Alexch, as having low suitability for most annual crops, but active tree regeneration in Kaleka shows sustainability. [ABSTRACT FROM AUTHOR]

Small water bodies including drainage ditches can be hotspots for methane (CH4) emissions from peatlands. We assessed the CH4 emissions of a drained and a rewetted temperate fen including emissions of managed and unmanaged drainage ditches over the course of 2.5 years, covering three vegetation periods. Ditch CH4 emissions in the rewetted fen were significantly higher than in the drained fen. In the rewetted fen ditches contributed up to 91% of the annual CH4 budget, despite covering only 1.5% of the area. In the drained fen CH4 emissions were solely made up of ditch emissions. When including CH4 uptake by the peat soil, the CH4 balance of the drained fen was neutral. Dissolved organic carbon concentrations likely had an enhancing effect on CH4 emissions while nitrate and sulfate in the ditch water seem to have had an inhibitory effect. Air and water temperature controlled seasonal variability of ebullitive as well as diffusive CH4 emissions. Ebullition contributed less than 10% to the overall CH4 budget in the ditches. Drainage ditches represent a hotspot of CH4 emissions and need therefore be taken into account when assessing the success of rewetting projects of peatlands. [ABSTRACT FROM AUTHOR]

Abstract Ecological restoration has great potential for reversing anthropogenic degradation, as it aims at the simultaneous recovery of several ecosystem functions and services. However, it can be challenging to evaluate multiple restoration targets based on a high number of indicators, and this calls for a multifunctionality approach. Multifunctionality is an integrated measure of the relative supply of multiple ecosystem functions or services. As temporal aspects are of key importance for ecosystem recovery, we analyzed multifunctionality against time since restoration. We used rewetted peatlands in a mountainous region in Central Germany as a study case. Restored peatlands are expected to become multifunctional, while their recovery is rather slow. We investigated to what extent rewetted peatlands recover, and how time since restoration controls the simultaneous development of multiple ecosystem properties. We studied restored peatlands with respect to plant diversity, water table, peat decomposition, water holding capacity, and nutrient level using a chronosequence of 0–18 yr after restoration. We analyzed the development of individual properties and of a combined index. We further compared the recovery of restored sites at different ages to an intact reference peatland and to a theoretical optimum value, defined as the mean of the eleven most desirable values observed. Eleven out of 13 peatland properties and the combined index significantly evolved with time since restoration. Nevertheless, we could not observe a consistent trend of multiple properties if aiming at highest levels of functioning, whereas there was progress with time if low or intermediate functioning is targeted. Our results show that not all functions of restored peatlands can recover to the most desirable extent within 18 yr. However, the average functionality and some individual properties achieved levels comparable to the reference site, highlighting that improvement is possible. While the integrated assessment informs about the degree of ecosystem recovery, an additional analysis of individual properties helps understanding ecosystem‐specific dynamics, which are needed for making decisions on potential future management.

Sphagnum farming provides a sustainable wet land use alternative for drained peatland agriculture. Since 2011 Sphagnum has been cultivated on formerly drained bog grassland at Hankhauser Moor in north-west Germany. The site has been rewetted and is equipped with an automatic irrigation system which controls the inflow and outflow of water. We used measurements and models to determine the amount of irrigation water needed to keep the water table just below the Sphagnum surface throughout the year. In winter there was a water surplus, whereas in spring and summer evapotranspiration exceeded precipitation, creating a water deficit. Next to evapotranspiration, horizontal seepage was a major cause of water loss. Modelling indicated that the amount of irrigation required to make up the water deficit in the dry hydrological year 2013 (November 2012 to October 2013) amounted to 359 mm (3,588 m³ ha-1). To compensate for the average water deficit over the 20-year period 1993–2013, 160 mm of water would be needed annually (i.e. 1,600 m³ ha-1 yr-1), but the maximum water deficit accumulated during that period was much higher, at 6,363 m³ ha-1. In relative terms, both evapotranspiration and seepage losses will decrease with increasing size of the rewetted area because drained surroundings enhance water losses from the wetter Sphagnum farming site, both as evapotranspiration due to advection (oasis effect) and as horizontal seepage due to steepening of hydraulic gradients. For successful Sphagnum farming the water demand must be considered and an appropriate water supply must be guaranteed.

Peatlands are significant global carbon stores and play an important role in mediating the flux of greenhouse gasses into the atmosphere. During the 20th century substantial areas of northern peatlands were drained to repurpose the land for industrial or agricultural use. Drained peatlands have dysfunctional microbial communities, which can lead to net carbon emissions. Rewetting of drained peatlands is therefore an environmental priority, yet our understanding of the effects of peatland drainage and rewetting on microbial communities is still incomplete. Here we summarize the last decade of research into the response of the wider microbial community, methane-cycling microorganisms, and micro-fauna to drainage and rewetting in fens and bogs in Europe and North America. Emphasis is placed on current research methodologies and their limitations. We propose targets for future work including: accounting for timescale of drainage and rewetting events; better vertical and lateral coverage of samples across a peatland; the integration of proteomic and metabolomic datasets into functional community analysis; the use of RNA sequencing to differentiate the active community from legacy DNA; and further study into the response of the viral and micro-faunal communities to peatland drainage and rewetting. This review should benefit researchers embarking on studies in wetland microbiology and non-microbiologists working on peatland drainage and rewetting in general. [ABSTRACT FROM AUTHOR]

Peatland rewetting aims at stopping the emissions of carbon dioxide (CO2) and establishing net carbon sinks. However, in times of global warming, restoration projects must increasingly deal with extreme events such as drought periods. Here, we evaluate the effect of the European summer drought 2018 on vegetation development and the exchange of methane (CH4) and CO2 in two rewetted minerotrophic fens (Hütelmoor—Hte and Zarnekow—Zrk) including potential carry-over effects in the post-drought year. Drought was a major stress factor for the established vegetation but also promoted the rapid spread of new vegetation, which will likely gain a lasting foothold in Zrk. Accordingly, drought increased not only respiratory CO2 losses but also photosynthetic CO2 uptake. Altogether, the drought reduced the net CO2 sink in Hte, while it stopped the persistent net CO2 emissions of Zrk. In addition, the drought reduced CH4 emissions in both fens, though this became most apparent in the post-drought year and suggests a lasting shift towards non-methanogenic organic matter decomposition. Occasional droughts can be beneficial for the restoration of the peatland carbon sink function if the newly grown vegetation increases CO2 sequestration in the long term. Nonetheless, care must be taken to prevent extensive peat decay. This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'. [ABSTRACT FROM AUTHOR]

Ecological restoration has great potential for reversing anthropogenic degradation, as it aims at the simultaneous recovery of several ecosystem functions and services. However, it can be challenging to evaluate multiple restoration targets based on a high number of indicators, and this calls for a multifunctionality approach. Multifunctionality is an integrated measure of the relative supply of multiple ecosystem functions or services. As temporal aspects are of key importance for ecosystem recovery, we analyzed multifunctionality against time since restoration. We used rewetted peatlands in a mountainous region in Central Germany as a study case. Restored peatlands are expected to become multifunctional, while their recovery is rather slow. We investigated to what extent rewetted peatlands recover, and how time since restoration controls the simultaneous development of multiple ecosystem properties. We studied restored peatlands with respect to plant diversity, water table, peat decomposition, water holding capacity, and nutrient level using a chronosequence of 0-18 yr after restoration. We analyzed the development of individual properties and of a combined index. We further compared the recovery of restored sites at different ages to an intact reference peatland and to a theoretical optimum value, defined as the mean of the eleven most desirable values observed. Eleven out of 13 peatland properties and the combined index significantly evolved with time since restoration. Nevertheless, we could not observe a consistent trend of multiple properties if aiming at highest levels of functioning, whereas there was progress with time if low or intermediate functioning is targeted. Our results show that not all functions of restored peatlands can recover to the most desirable extent within 18 yr. However, the average functionality and some individual properties achieved levels comparable to the reference site, highlighting that improvement is possible.While the integrated assessment informs about the degree of ecosystem recovery, an additional analysis of individual properties helps understanding ecosystem-specific dynamics, which are needed for making decisions on potential future management. [ABSTRACT FROM AUTHOR]

Increased agricultural use of tropical peatlands has negative environmental effects. Drainage leads to landscape-wide degradation and fire risks. Livelihood strategies in peatland ecosystems have traditionally focused on transitions from riverbanks to peatland forests. Riparian ‘Kaleka’ agroforests with more than 100 years of history persist in the peatlands of Central Kalimantan (Indonesia), where large-scale open-field agricultural projects have dramatically failed. Our field study in a Dayak Ngaju village on the Kahayan river in the Pulang Pisau district involved characterizing land uses, surveying vegetation, measuring soil characteristics, and monitoring groundwater during a period of 16 months. We focused on how local practices and farmer knowledge compare with standard soil fertility (physical, chemical, biological) measurements to make meaningful assessments of risks and opportunities for sustainable land use within site-specific constraints. The Kaleka agroforests around a former settlement and sacred historical meaning are species-rich agroforests dominated by local fruit trees and rubber close to the riverbank. They function well with high wet-season groundwater tables (up to −15 cm) compatible with peatland restoration targets. Existing soil quality indices rate the soils, with low soil pH and high Alexch, as having low suitability for most annual crops, but active tree regeneration in Kaleka shows sustainability.

In 2013, a pilot experimental field of about 15 ha was set up within the basin of Lake Massaciuccoli (Tuscany, Italy) in order to compare different management strategies—a paludicultural system (PCS), a constructed wetland system (CWS), a nearly-natural wetland system (NWS)—for peatland restoration after almost a century of drainage-based agricultural use (CS). After five years, changes in peat soil quality were investigated from a chemical, biochemical, and ecoenzymatic perspective. The soil in CS was mainly characterized by oxidant conditions, higher content of overall microbial activity, low levels of easily available phosphorus for vegetation, and medium total carbon content ranging from 25.0% to 30.7%. In PCS, the levels of total carbon and the content of bioavailable P were higher, while the oxidant conditions were lower compared to the other systems. As expected, the soils in CWS and NWS were characterized by the most reduced conditions and by the highest levels of arylsulphatase activity. It was noteworthy that soils in the NWS systems were characterized by the highest level of nonavailable P. Outputs from ecoenzymatic activity confirmed the physico-chemical and biochemical results.

Risk factors in agriculture and forestry are examined in connection with inundation of ameliorated peatlands. Feasibility of peatland rewetting for prevention of wildfires is considered on the example of Ryazan Meshchera. To study risks, a comprehensive approach, combining prediction of ameliorated landscape performance and analytical modeling, is employed. The main hypothesis is related to continuity of natural conditions of these reclaimed lands subject to continuous influence of an artificial drainage network. The analysis of risk factors was performed for the four types of landscape amelioration districts of Ryazan Meshchera: moraine-formed fluvio-glacial plains, interfluvial sandur plains of the Moscow stage, valley sandurs and terraces above the floodplains of the Oka River, and sandur lacustrine plains. The districts were compared according to the degree of their “peatification” (ratio of peatlands to total area), groundwater depth, and extent and density of the open-channel drainage network. It appears that the type four district has the largest fraction of peatlands (60% and more); in the districts of type two and three, peatlands occupy 20-30%. When building an analytical model for assessing change in land value as a result of rewetting of fire-prone peatlands, it is proposed to apply a methodology of applied information economics. This methodology allows quantifying noneconomic factors in the presence of risks and uncertainties. The employed approaches largely involve the Fermi estimate, which is a decomposition of affecting factors into elementary components and estimation of their inherent uncertainties, and the Monte Carlo method, which is numerical modeling of possible scenarios of event developments under artificially generated random events with the probabilities corresponding to that earlier determined by Fermi estimation. It is assumed that, during the implementation of the Wetlands International program aimed to change amelioration status of lands that contain fire-prone peat bogs in the Ryazan part of Meshchera, substantial costs will be incurred not only in rewetting but also in eliminating the damage caused, which can be calculated with the help of the proposed analytical model. [ABSTRACT FROM AUTHOR]

MoorFutures® is the world's first carbon credit scheme from peatland rewetting. Thus far, MoorFutures® rely on proxies (greenhouse gas emission site types or GESTs) to estimate emission reductions. Here, we tested the profitability of including direct greenhouse gas (GHG) measurements of project emissions for a range of rewetting costs and vegetation scenarios based on a hypothetical MoorFutures® project. In almost all scenarios GEST assessments underestimated emission reductions compared with direct measurements. Including direct measurements was lucrative in > 50% of all vegetation scenario/rewetting cost combinations with net profits ranging from EUR − 8.18 to 26.31 per certificate. Profitability was achieved at rewetting costs of ~ EUR 5400 ha − 1 upward. More sophisticated GHG measurements became profitable at twice the rewetting costs. In cases where direct flux measurements do not generate a profit they can strengthen reliability and buyers' trust and thus support higher prices of the certificates. [ABSTRACT FROM AUTHOR]

The climate mitigation potential of tropical peatlands has gained increased attention as Southeast Asian peatlands are being deforested, drained and burned at very high rates, causing globally significant carbon dioxide (CO) emissions to the atmosphere. We used a process-based dynamic tropical peatland model to explore peat carbon (C) dynamics of several management scenarios within the context of simulated twenty-first century climate change. Simulations of all scenarios with land use, including restoration, indicated net C losses over the twenty-first century ranging from 10 to 100 % of pre-disturbance values. Fire can be the dominant C-loss pathway, particularly in the drier climate scenario we tested. Simulated 100 years of oil palm ( Elaeis guineensis) cultivation with an initial prescribed burn resulted in 2400-3000 Mg CO ha total emissions. Simulated restoration following one 25-year oil palm rotation reduced total emissions to 440-1200 Mg CO ha, depending on climate. These results suggest that even under a very optimistic scenario of hydrological and forest restoration and the wettest climate regime, only about one third of the peat C lost to the atmosphere from 25 years of oil palm cultivation can be recovered in the following 75 years if the site is restored. Emissions from a simulated land degradation scenario were most sensitive to climate, with total emissions ranging from 230 to 10,600 Mg CO ha over 100 years for the wettest and driest dry season scenarios, respectively. The large difference was driven by increased fire probability. Therefore, peat fire suppression is an effective management tool to maintain tropical peatland C stocks in the near term and should be a high priority for climate mitigation efforts. In total, we estimate emissions from current cleared peatlands and peatlands converted to oil palm in Southeast Asia to be 8.7 Gt CO over 100 years with a moderate twenty-first century climate. These emissions could be minimized by effective fire suppression and hydrological restoration. [ABSTRACT FROM AUTHOR]

Drainage and agricultural use transform natural peatlands from a net carbon (C) sink to a net C source. Rewetting of peatlands, despite of high methane (CH 4 ) emissions, holds the potential to mitigate climate change by greatly reducing CO 2 emissions. However, the time span for this transition is unknown because most studies are limited to a few years. Especially, nonpermanent open water areas often created after rewetting, are highly productive. Here, we present 14 consecutive years of CH 4 flux measurements following rewetting of a formerly long-term drained peatland in the Peene valley. Measurements were made at two rewetted sites (non-inundated vs. inundated) using manual chambers. During the study period, significant differences in measured CH 4 emissions occurred. In general, these differences overlapped with stages of ecosystem transition from a cultivated grassland to a polytrophic lake dominated by emergent helophytes, but could also be additionally explained by other variables. This transition started with a rapid vegetation shift from dying cultivated grasses to open water floating and submerged hydrophytes and significantly increased CH 4 emissions. Since 2008, helophytes have gradually spread from the shoreline into the open water area, especially in drier years. This process was periodically delayed by exceptional inundation and eventually resulted in the inundated site being covered by emergent helophytes. While the period between 2009 and 2015 showed exceptionally high CH 4 emissions, these decreased significantly after cattail and other emergent helophytes became dominant at the inundated site. Therefore, CH 4 emissions declined only after 10 years of transition following rewetting, potentially reaching a new steady state. Overall, this study highlights the importance of an integrative approach to understand the shallow lakes CH 4 biogeochemistry, encompassing the entire area with its mosaic of different vegetation forms. This should be ideally done through a study design including proper measurement site allocation as well as long-term measurements., (© 2023 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Rewetting can strongly affect the matter balance of peatlands. Owing to evidence of increasing CH emissions and P mobilisation after rewetting, the effects of peatland restoration on climate, eutrophication risks and related controversies are discussed. Our study focuses on the role of helophytes in the carbon and nutrient balance of rewetted fen grasslands of NE Germany. We hypothesise that the helophytes Carex riparia, Glyceria maxima, Phalaris arundinacea, Phragmites australis and Typha latifolia differ in biomass production and nutrient standing stock according to site conditions and harvest time. We analysed the helophyte biomass three times a year and continuously measured water levels and quality. Biomass production, nutrient standing stock and litter accumulation were highly species specific and depended on nutrient availability, mean water levels and harvesting time. We conclude that helophytes store considerable amounts of carbon and temporarily improve the water quality by withdrawing high amounts of nutrients from the top soil during the growing season, and by reducing nutrient discharges. Restoring peatlands as effective nutrient and carbon sinks in the landscape should favour highly productive potentially peat-forming helophytes as Phragmites australis by establishing adequate water levels. If nutrients are to be removed from the degraded peatland, then management can combine the restoration of helophyte stands by rewetting with harvesting measures. [ABSTRACT FROM AUTHOR]

Paludiculture, the cultivation of crops on rewetted peatlands, is often proposed as a viable climate change mitigation option that reduces greenhouse gas emissions (GHGe), while simultaneously providing novel agricultural business options. In West Europe, experiments are ongoing in using the paludicrop cattail (Typha spp.) as feedstock for insulation panel material. Here, we use a Dutch case study to investigate the environmental potential and economic viability of shifting the use of peat soils from grassland (for dairy production) to Typha paludiculture (for cultivation and insulation panel production). Using a life cycle assessment and cost-benefit analysis, we compared the global warming potential (GWP), yearly revenues and calculated Net Present Value (NPV) of 1 ha Dutch peat soil used either for dairy production or for Typha paludiculture. We estimated that changing to Typha paludiculture leads to a GWP reduction of ~32% (16.4 t CO 2 -eq ha -1 ), mainly because of lower emissions from peat decomposition as a result of land-use management (-21.6 t CO 2 -eq ha -1 ). If biogenic carbon storage is excluded, the avoided impact of conventional insulation material is insufficient to compensate the impact of cultivating and processing Typha (9.7 t CO 2 -eq ha -1 ); however, this changes if biogenic carbon storage is included (following PAS2050 guidelines). Typha paludiculture is currently not competitive with dairy production, mainly due to high cultivation costs and low revenues, which are both uncertain, and will likely improve as the system develops. Its NPV is negative, mainly due to high investment costs. This can be improved by introducing carbon credits, with carbon prices for Typha paludiculture (30 years) comparable to EU-ETS prices. In conclusion, Dutch Typha paludiculture has a significant climate change mitigation potential by reducing emissions from deep drained peatlands. Nevertheless, attention is needed to increase its economic viability as this is a key aspect of the system change., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

In 2013, a pilot experimental field of about 15 ha was set up within the basin of Lake Massaciuccoli (Tuscany, Italy) in order to compare different management strategies—a paludicultural system (PCS), a constructed wetland system (CWS), a nearly-natural wetland system (NWS)—for peatland restoration after almost a century of drainage-based agricultural use (CS). After five years, changes in peat soil quality were investigated from a chemical, biochemical, and ecoenzymatic perspective. The soil in CS was mainly characterized by oxidant conditions, higher content of overall microbial activity, low levels of easily available phosphorus for vegetation, and medium total carbon content ranging from 25.0% to 30.7%. In PCS, the levels of total carbon and the content of bioavailable P were higher, while the oxidant conditions were lower compared to the other systems. As expected, the soils in CWS and NWS were characterized by the most reduced conditions and by the highest levels of arylsulphatase activity. It was noteworthy that soils in the NWS systems were characterized by the highest level of nonavailable P. Outputs from ecoenzymatic activity confirmed the physico-chemical and biochemical results. [ABSTRACT FROM AUTHOR]