Rewetting of Cutaway Peatlands: Are We Re‐Creating Hot Spots of Methane Emissions?
Rewetting of Cutaway Peatlands: Are We Re‐Creating Hot Spots of Methane Emissions?
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DOI：
10.1111/j.1526-100x.2008.00416.x
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发表时间：
2009-11
影响因子：
3.2
通讯作者：
David Wilson;J. Alm;J. Laine;K. Byrne;E. Farrell;E. Tuittila
中科院分区：
文献类型：
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作者：
David Wilson;J. Alm;J. Laine;K. Byrne;E. Farrell;E. Tuittila
甲烷排放热点是微型场地和景观尺度上原始泥炭地的典型特征。为了确定剖面泥炭地的再润湿和湖泊建设是否会导致热点的重新产生，我们首先使用静态室测量了 2 年期间的 CH4 通量并估计了年排放量。其次，为了评估再湿润和湖泊形成是否会在景观层面产生热点，我们假设了泥炭地停止开采后泥炭地的许多替代土地利用方案。利用本研究的结果和其他文献研究的结果，我们计算了每种情景的全球变暖潜势 (GWP) 以及 CH4 各自的贡献。结果表明，由于地下水位（WT）位置和植物生产力的微场所特定差异，观察到了 CH4 通量的热点。 CH4通量与10cm深度泥炭温度和WT位置密切相关。 2002 年的年排放量为 4.3 至 38.8 g CH4 m−2 yr−1，2003 年的年排放量为 3.2 至 28.8 g CH4 m−2 yr−1。情景结果表明，湖泊的形成可能会导致景观层面热点的重新产生。然而，从剖面生态系统到湿地生态系统的转变可能会导致泥炭地的全球升温潜能值降低。
Hot spots of CH4 emissions are a typical feature of pristine peatlands at the microsite and landscape scale. To determine whether rewetting and lake construction in a cutaway peatland would result in the re‐creation of hot spots, we first measured CH4 fluxes over a 2‐year period with static chambers and estimated annual emissions. Second, to assess whether rewetting and lake creation would produce hot spots at the landscape level, we hypothesized a number of alternative land use scenarios for the peatland following the cessation of peat extraction. Using the results from this study and other studies from literature, we calculated the global warming potential (GWP) of each scenario and the respective contribution of CH4. The results showed that hot spots of CH4 fluxes were observed as a consequence of microsite‐specific differences in water table (WT) position and plant productivity. CH4 fluxes were closely related to peat temperature at 10 cm depth and WT position. Annual emissions ranged from 4.3 to 38.8 g CH4 m−2 yr−1 in 2002 and 3.2 to 28.8 g CH4 m−2 yr−1 in 2003. The scenario results suggest that lake creation is likely to result in the re‐creation of a hot spot at the landscape level. However, the transition from cutaway to wetland ecosystem may lead to a reduction in the GWP of the peatland.