Research Center for Scientific Development in Fenhe River Valley, Taiyuan Normal University, Jinzhong, Shanxi, PR China.
College of Atmospheric Sciences, Lanzhou University, No. 222 Tianshui South Road, Chengguan District, Lanzhou, 730000, PR China.
Environ Pollut. 2022 May 15;301:119041. doi: 10.1016/j.envpol.2022.119041. Epub 2022 Feb 22.
European natural peatlands have undergone long-term anthropogenic drainage activities that have severely decreased their functions, such as carbon sequestration. Recent rewetting has been conducted to restore the ecosystem services of peatlands and mitigate the emissions of potent greenhouse gases such as nitrous oxide (NO). However, the magnitudes and spatial patterns of annual NO fluxes and their mitigation potentials across European peatlands remain unknown. Here, we synthesized 492 annual NO flux data points from 77 in situ studies across European peatlands and found that the soil annual NO fluxes varied extensively from -1.08 to 33.40 kg NO-N ha yr; these results were significantly and interactively (P < 0.05) affected by the peatland status, climatic regime and nutrient supply type. Drainage significantly (P < 0.05) stimulated soil NO emissions from natural minerotrophic rather than ombrotrophic peatlands, regardless of the climatic regime. Similarly, rewetting significantly (P < 0.05) reduced soil NO emissions from drained minerotrophic rather than ombrotrophic peatlands, demonstrating that the high NO emissions were driven by a simultaneous decline in the water table depth and increase in the soil nitrogen (N) availability. Magnitudes of the increases or decreases in NO emissions due to drainage or rewetting were also significantly influenced by the land-use and drainage history before rewetting and in the years following drainage/rewetting, respectively. The estimated annual mean NO emission total was found to be 90.42 (95% confidence interval: 64.49-122.57) Gg NO-N in 2020 from European peatlands. Scenario analysis showed that drained peatlands should be rewetted expeditiously; postponing rewetting would cause larger emissions from continued NO emissions from drained peatlands. Fully rewetting the drained peatlands used for forestry and peat extraction and partially rewetting those used for agriculture and grassland comprise a strategy for mitigating drained peatland NO emissions without compromising food security.
欧洲天然泥炭地经历了长期的人为排水活动，其功能（如碳固存）严重下降。最近的湿地恢复工作旨在恢复泥炭地的生态系统服务，并减轻一氧化二氮（NO）等强效温室气体的排放。然而，欧洲泥炭地的年一氧化二氮通量的幅度和空间格局及其缓解潜力仍不清楚。在这里，我们综合了 77 项欧洲泥炭地原位研究的 492 个年度一氧化二氮通量数据点，发现土壤年一氧化二氮通量变化范围很大，从-1.08 到 33.40 kg NO-N ha yr；这些结果受到泥炭地状态、气候条件和养分供应类型的显著和交互（P < 0.05）影响。排水显著（P < 0.05）刺激了天然矿质而非腐殖质泥炭地的土壤一氧化二氮排放，无论气候条件如何。同样，湿地恢复显著（P < 0.05）降低了排水的矿质泥炭地而非腐殖质泥炭地的土壤一氧化二氮排放，表明高一氧化二氮排放是由于地下水位深度同时下降和土壤氮（N）供应增加所致。排水或湿地恢复引起的 NO 排放量的增加或减少幅度也分别受到湿地恢复前的土地利用和排水历史以及排水/湿地恢复后的年份的显著影响。据估计，2020 年欧洲泥炭地的年平均一氧化二氮排放总量为 90.42（95%置信区间：64.49-122.57）Gg NO-N。情景分析表明，应迅速对排水泥炭地进行湿地恢复；推迟湿地恢复将导致排水泥炭地持续排放一氧化二氮，从而产生更大的排放。对用于林业和泥炭开采的排水泥炭地进行全面湿地恢复，对用于农业和草地的排水泥炭地进行部分湿地恢复，是在不影响粮食安全的情况下缓解排水泥炭地一氧化二氮排放的一种策略。
