Carbon and climate implications of rewetting a raised bog in Ireland

作者：David Wilson, Francis Mackin, Juha‐Pekka Tuovinen, Gerald M. Moser, Catherine Farrell, Florence Renou‐Wilson · 发表于：Global Change Biology · 年份：2022 · DOI：10.1111/gcb.16359 · 被引用次数：51 · 研究领域：Peatlands and Wetlands Ecology、Coastal wetland ecosystem dynamics、Geology and Paleoclimatology Research

Abstract Peatland rewetting has been proposed as a vital climate change mitigation tool to reduce greenhouse gas emissions and to generate suitable conditions for the return of carbon (C) sequestration. In this study, we present annual C balances for a 5‐year period at a rewetted peatland in Ireland (rewetted at the start of the study) and compare the results with an adjacent drained area (represents business‐as‐usual). Hydrological modelling of the 230‐hectare site was carried out to determine the likely ecotopes (vegetation communities) that will develop post‐rewetting and was used to inform a radiative forcing modelling exercise to determine the climate impacts of rewetting this peatland under five high‐priority scenarios (SSP1‐1.9, SS1‐2.6, SSP2‐4.5, SSP3‐7.0 and SSP5‐8.5). The drained area (marginal ecotope) was a net C source throughout the study and emitted 157 ± 25.5 g C m −2 year −1 . In contrast, the rewetted area (sub‐central ecotope) was a net C sink of 78.0 ± 37.6 g C m −2 year −1 , despite relatively large annual methane emissions post‐rewetting (average 19.3 ± 5.2 g C m −2 year −1 ). Hydrological modelling predicted the development of three key ecotopes at the site, with the sub‐central ecotope predicted to cover 24% of the site, the sub‐marginal predicted to cover 59% and the marginal predicted to cover 16%. Using these areal estimates, our radiative forcing modelling projects that under the SSP1‐1.9 scenario, the site will have a warming effect on the climate...