Spatial Extent, Age, and Carbon Stocks in Drained Thaw Lake Basins on the Barrow Peninsula, Alaska
Spatial Extent, Age, and Carbon Stocks in Drained Thaw Lake Basins on the Barrow Peninsula, Alaska
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阿拉斯加巴罗半岛排水解冻湖盆地的空间范围、年龄和碳储量
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发表时间：
2003
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通讯作者：
X. Dai
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作者：
K. Hinkel;W. Eisner;J. Bockheim;F. Nelson;K. Peterson;X. Dai
摘要在阿拉斯加的北极沿岸平原上，解冻湖和排干的解冻湖盆是普遍存在的。盆地是潮湿的沉积环境，非常适合有机物质的积累和保存。大部分土壤有机碳（SOC）目前被封存在近地表永久冻土中，但在变暖的情况下，可能会被调动。巴罗半岛上的77个盆地的相对年龄估计使用的植物群落演替的程度和验证的放射性碳测年材料收集的有机层的基础上，在21个盆地。利用该地区的Landsat-7+图像，从流域年龄相关的光谱和纹理开发了一种神经网络分类算法。该地区约22%的面积被592个湖泊（>1公顷）覆盖，至少50%的陆地表面被558个排水湖盆覆盖。从盆地采集的岩芯分析表明：（1）有机层厚度和有机质分解程度一般随盆地年龄的增加而增加;（2）表层有机层中的SOC随盆地年龄的增加而增加，但由于冷扰动、有机质分解和导致上部冻土中冰富集的过程，表层100 cm土壤中的SOC的关系变得模糊。
Abstract Thaw lakes and drained thaw lake basins are ubiquitous on the Arctic Coastal Plain of Alaska. Basins are wet depositional environments, ideally suited for the accumulation and preservation of organic material. Much of this soil organic carbon (SOC) is currently sequestered in the near-surface permafrost but, under a warming scenario, could become mobilized. The relative age of 77 basins on the Barrow Peninsula was estimated using the degree of plant community succession and verified by radiocarbon-dating material collected from the base of the organic layer in 21 basins. Using Landsat-7+ imagery of the region, a neural network classifying algorithm was developed from basin age-dependent spectra and texture. About 22% of the region is covered by 592 lakes (>1 ha), and at least 50% of the land surface is covered by 558 drained lake basins. Analysis of cores collected from basins indicates that (1) organic layer thickness and the degree of organic matter decomposition generally increases with basin age, and (2) SOC in the surface organic layer tends to increase with basin age, but the relation for the upper 100 cm of soil becomes obscured due to cryoturbation, organic matter decomposition, and processes leading to ice enrichment in the upper permafrost.