The ecohydrology and biogeochemistry of northern peatland ecosystems

泥炭地生态系统含有约25%的世界陆地活性碳，是大气甲烷的重要来源。鉴于其地理位置，它们在今后几十年中可能会经历重大的气候和/或土地使用变化。为了预测北方泥炭地的命运，我们需要了解气候、水文和生态过程如何决定泥炭地的结构和功能。我的研究计划是指导三个首要问题：什么是物理，化学和生态控制的形成和发展的泥炭地生态系统在北方和北极地区？北方泥炭地在气候-碳耦合系统中的作用是什么？环境变化将如何改变泥炭地的结构和功能？我的发现研究的目标是：1）检查泥炭地微观和中观地形，水文（地下水位），植被和碳（泥炭）积累之间的反馈; 2）调查模式如何形成和维持泥炭地，重点是控制地球化学转化的热力学限制的因素; 3）确定泥炭地结构和水文如何随着冻土的融化而变化。 将泥炭地视为复杂适应系统（CAS），表明泥炭地形态的产生和维持是水文、植物生产、分解和土壤地球化学之间的负反馈作用的结果。在CAS的背景下，我假设地形的规模和方差是生态系统的复杂性的函数，方差越规则，泥炭地的控制范围越大，外部强迫变量的变化-即更大的稳定性。 我建议，在泥炭地的地形变化的结构是一个新兴的自我调节的属性。我将试图通过理论和实证研究来证伪这些假设。 这项研究的结果将有助于确定未来环境变化中泥炭地碳储量的命运。

Peatland ecosystems contain about 25% of the world's active terrestrial carbon and are significant sources of atmospheric methane. Given their geographic location they will likely experience significant climate and/or land-use change over the next decades. To project the fate of northern peatlands we need to understand how climate, hydrology, and ecological processes determine peatland structure and function. My research program is guided for three overarching questions: What are the physical, chemical and ecological controls of the formation and development of peatland ecosystems in the boreal and arctic regions?; What is the role of northern peatlands in the couple climate-carbon system?; and How will environmental change alter the structure and function of peatlands? The objectives of my Discovery research are to: 1) examine the feedbacks among peatland micro- and mesotopography, hydrology (water table), vegetation, and carbon (peat) accumulation; 2) investigate how patterns form and are maintained on peatlands, focussing on factors that control the thermodynamic limits of biogeochemical transformations; and 3) determine how peatland structure and hydrology change with the thawing of permafrost. Treating peatlands as complex adaptive systems (CAS) shows the production and maintenance of peatland form results from several negative feedbacks among hydrology, plant production, decomposition, and biogeochemistry. Within the context of CASs I hypothesize that scale and variance of topography is a function of the ecosystem's complexity and the more regular the variance the greater the range of control a peatland has to changes in external forcing variables - i.e. greater stability. I propose that the structure of the variance in a peatland's topography is an emergent property of self-regulation. I will attempt to falsify these hypotheses through both theoretical and empirical studies. The results of this research will help determine the fate of the peatland carbon store in future environmental change.