Changes in peatland biogeochemistry

我的研究计划决定了水文、气候、生态系统结构和功能如何相互作用，以控制陆地生态系统中的生物地球化学循环。我目前计划的重点是北部泥炭地，因为它们在全新世和当代碳循环中具有潜在的重要性，因此也是气候。泥炭地的泥炭代表了大气中二氧化碳的巨大(~400pgC)的去除，泥炭的缺氧分解是大气CH4的来源。泥炭地与水文学有着复杂和适应性的联系，在北部地区是永久冻土。超过30%的泥炭地位于永久冻土区。气候预测表明，到2100年，活跃层深度增加，地表水文学随之发生变化。多年冻土流失将改变泥炭地的生物地球化学和植被结构，但关于气候、水文和泥炭地生态系统功能和结构之间的启发式联系的研究很少。温室生物地球化学的变化相对于地表气候植被结构变化的直接影响--例如反照率和能量分配--的相对重要性如何？以及永冻层的消失是否影响水中碳的损失？等一阶问题尚未得到解决。模拟模型缺乏必要的功能来模拟这些变化，DOC输出路径在很大程度上被忽略了，尽管它看起来与大气净交换的量级相同。

My research program determines how hydrology, climate, and ecosystem structure and function interact to control biogeochemical cycling in terrestrial ecosystems. The current focus of my program is on northern peatlands because of their potential importance in Holocene and contemporary carbon cycle, and hence climate. The 'peat' of peatlands represents a huge (~ 400 Pg C) removal of atmospheric CO2, and the anoxic decomposition of peat is a source of atmospheric CH4. Peatlands are complexly and adaptively linked to hydrology, and in northern regions permafrost. Over 30% of peatlands are located in permafrost regions. Climate predictions indicate that by 2100 an increase in active layer depth, with consequent changes in surface hydrology. Permafrost loss will alter both peatland biogeochemistry and vegetation structure but there has been little research on the heuristic links among climate, hydrology and peatland ecosystem function and structure. First order questions such as 'What is the relative importance of changes in greenhouse biogeochemistry compared to the direct affects of changes in vegetation structure of surface climate - e.g. albedo and energy partitioning?', and "Does permafrost loss affect the water borne loss of carbon?', have yet to be addressed. Simulation models lack the necessary functions to simulate these changes, and DOC export pathway has largely been ignored even though it appears to be of the same order of magnitude as the net atmospheric exchanges.