Rewetting Boreal Peatlands: Restoring Carbon Function?

作者：Nigel T. Roulet, Sara Knox, Shane Regan · 发表于：Global Change Biology · 年份：2025 · DOI：10.1111/gcb.70200 · 被引用次数：3 · 研究领域：Peatlands and Wetlands Ecology、Botany and Plant Ecology Studies、Coastal wetland ecosystem dynamics

Peatlands contain some 500 ± 100 Pg of carbon (Yu 2012) stored as partially decomposed plant litter—that is, peat, even though they represent less than 4% of the terrestrial landscape (UNEP 2022). Peatlands are generally low to moderate net primary production (NPP) ecosystems but also have disproportionately low decomposition rates (i.e., ecosystem respiration—ER) than most other ecosystems due to the presence of high moisture contents inhibiting the diffusion of oxygen into the peat. This promotes more significant anaerobic decomposition, enhancing the storage of carbon in the undecomposed litter, but also leads to considerable emission of methane (CH4). The slight imbalance of NPP over ER for millennia has resulted in a significant global store of terrestrial carbon. On a worldwide scale, the accumulation of atmospheric CO2 as peat over time has resulted in net climatic cooling (Frolking and Roulet 2007). A reduction of the water stored in a peatland can increase aerobic activity, increase decomposition, and alter the imbalance to favor ER over NPP. Land use changes that involve peatland drainage typically result in peatlands becoming a source of atmospheric CO2 rather than a sink. Approximately 12% of peatlands have been degraded, which usually involves some form of drainage (UNEP 2022). Degraded peatlands emit between 0.5 to 1 Pg C yr−1 (Leifeld and Menichetti 2018), which is equivalent to 5 to 10% of the 2014–2023 average anthropogenic emission of CO2 (The Global Carbon ...