Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada.
Nat Commun. 2011 Nov 1;2:514. doi: 10.1038/ncomms1523.
For millennia, peatlands have served as an important sink for atmospheric CO(2) and today represent a large soil carbon reservoir. While recent land use and wildfires have reduced carbon sequestration in tropical peatlands, the influence of disturbance on boreal peatlands is uncertain, yet it is important for predicting the fate of northern high-latitude carbon reserves. Here we quantify rates of organic matter storage and combustion losses in a boreal peatland subjected to long-term experimental drainage, a portion of which subsequently burned during a wildfire. We show that drainage doubled rates of organic matter accumulation in the soils of unburned plots. However, drainage also increased carbon losses during wildfire ninefold to 16.8±0.2 kg C m(-2), equivalent to a loss of more than 450 years of peat accumulation. Interactions between peatland drainage and fire are likely to cause long-term carbon emissions to far exceed rates of carbon uptake, diminishing the northern peatland carbon sink.
数千年来，泥炭地一直是大气 CO(2) 的重要汇，也是巨大的土壤碳库。尽管最近的土地利用和野火减少了热带泥炭地的碳固存，但干扰对北方泥炭地的影响尚不确定，但这对于预测北方高纬度碳储量的命运很重要。在这里，我们量化了经历长期实验性排水的北方泥炭地以及其中一部分随后在野火中燃烧的部分的有机物质储存和燃烧损失的速率。我们发现，排水使未燃烧样地的土壤中有机物质的积累速率增加了一倍。然而，排水也使野火期间的碳损失增加了九倍，达到 16.8±0.2 kg C m(-2)，相当于超过 450 年的泥炭积累损失。泥炭地排水和火灾之间的相互作用可能导致长期碳排放远远超过碳吸收速率，从而减少北方泥炭地碳汇。
