On the functional role of diversity and trophic interactions in litter decomposition of forest ecosystems

随着人类活动导致的生物多样性损失日益增加，科学和社会的优先事项之一是了解多样性和/或物种组成的变化是否以及如何影响生态系统功能。我的研究重点是森林生态系统，它为超过65%的陆地生物多样性提供了栖息地，我的研究项目调查了多样性在凋落物分解和养分循环的生态系统功能中的作用。长期目标是通过为北方、温带和热带森林生态系统中日益复杂的森林地面群落多营养模型提供新的实验证据，检验生物多样性科学中的理论预测。为了了解这些森林地面群落营养水平之间的相互作用，我的实验室将(1)量化原生林和次生林中凋落叶、根凋落叶和粗木屑的分解速率，(2)表征这些森林中土壤大型动物群落（腐食动物和捕食动物）的特征，(3)编制一个腐殖物的功能特征数据库，(4)利用腐食动物-腐食动物-捕食动物实验模型，共同开发和检验目前关于多样性和营养相互作用的理论。将营养复杂性纳入我们对生物多样性-生态系统功能的理解是具有挑战性的，但被认为是对森林群落和生态系统的生物多样性变化后果进行更相关预测的必要步骤。该研究项目将对生物多样性在生态系统功能中的作用提供新的见解，并为社会在当前全球变化的背景下面对日益严峻的环境挑战提供科学依据。这种基础研究对于为森林生态系统保护政策提供信息是必要和直接相关的。它还将为改进森林生物地球化学模型提供新的试验田数据，目前所有这些模型在准确预测土壤碳的能力方面都受到严重限制。

With increasing biodiversity loss due to human-induced activities, one of the emerging priorities for science and society is to understand if and how changes in diversity and/or species composition impact ecosystem function. With a particular emphasis on forest ecosystems that provide habitat to over 65% of terrestrial biodiversity, my research program investigates the role of diversity on the ecosystem functions of litter decomposition and nutrient cycling. The long-term objective is to test theoretical predictions in biodiversity science by providing novel experimental evidence for increasingly complex multi-trophic models of forest floor communities in boreal, temperate and tropical forest ecosystems. To understand interactions between and among trophic levels in these forest floor communities, my lab will (1) quantify decomposition rates of leaf litter, root litter and coarse woody debris in primary and secondary forests, (2) characterize soil macrofauna communities (detritivores and predators) in these forests, (3) compile a functional trait database for detritus, detritivores and their soil predators to calculate functional diversity of these communities and (4) co-develop and test current theory on diversity and trophic interactions using a detritus-detrivore-predator experimental model. Incorporating trophic complexity in our understanding of biodiversity-ecosystem functioning is challenging, but recognized as the necessary next step for more relevant predictions of the consequences of biodiversity change for forest communities and ecosystems. This research program will provide new insight into the role of biodiversity in ecosystem function and provide society with a scientific basis to face growing environmental challenges in the current context of global change. Such fundamental research is necessary and directly relevant for informing policy on conservation of forest ecosystems. It will also provide novel experimental field data for improving forest biogeochemical models that all currently suffer severe limitations in their ability to accurately predict soil carbon.