Rewetting of Disused Drained Peatlands and Reduction of Greenhouse Gas Emissions

Abstract

Drained peatlands are a significant source of greenhouse gas emissions to the atmosphere. When abandoned, they become the most likely sites of peat fires. An effective way to reduce greenhouse gas emissions and prevent peatland fires in disused drained peatlands is through rewetting and wetland restoration. These can make significant contributions to the implementation of the Paris Climate Agreement within the Land Use, Land-Use Change and Forestry sector and, ultimately, to climate change mitigation. An approach for estimating greenhouse gas emission reductions following rewetting, applicable to national and regional accounting, as well as to specific rewetting projects, is presented. It includes a methodology for determining effectively rewetted areas that can be considered wetlands, the application of IPCC greenhouse gas emission factors to said sites, and an uncertainty assessment. Starting from 2020 the Russian Federation National Report of anthropogenic emissions by sources and removals by sinks of greenhouse gasses not controlled by the Montreal Protocol utilised this approach in its inclusion of rewetted peatlands. An assessment of greenhouse gas emission reductions is presented using the example of a 1500 ha section of a peatland within the Fire Hazardous Peatland Rewetting Programme in Moscow Oblast (2010–2013). CO2 emission reductions were cumulatively 33.4 thous. t by 2022 (taking into account nitrous oxide fluxes, dissolved organic carbon removal and increased CH4 emissions—20 thous. t CO2-eq.) and are projected to reach almost 113 (68) thous. t by 2050. Greenhouse gas emission reductions not yet included as well as possible ways of accounting for them in the future are also noted.