Soil Biodiversity and Ecosystem Function under Climate Change

生物多样性的丧失是当今世界生态系统健康面临的最大威胁。由于与土地利用变化、污染、过度开发和气候变化相关的生境丧失和碎片化，许多生态系统目前正在经历生物多样性的戏剧性变化。我的研究将提供必要的科学，通过揭示生物多样性丧失的驱动因素，以及生物多样性丧失对生态系统过程和功能的影响，来帮助减轻这种损失。由于有明确的证据将全球变化、土壤生物多样性和养分循环的影响联系在一起，我的研究使用陆地-碎屑系统来实验研究全球变化背景下生物多样性的调节和功能意义，特别是关于森林土壤中的碳固存和氮素动态。我使用两种方法来获得对土壤生物多样性的准确评估，计算生物中介过程的速率，并通过详细的营养分析来衡量生态系统功能；一种是食物网方法，用于了解群落内物种之间的相互作用；另一种方法是质量平衡法，用于说明营养物质和能量在食物网中的移动。在接下来的五年里，我的实验室将在北方森林开发长期的野外场地，并在受控的实验室条件下创建中观生态系统，以隔离驱动全球变化、生物多样性和养分循环之间关系的生态机制。该计划将解决生物多样性的变化如何等同于生态系统水平过程的变化，如果这些变化决定了系统是成为净碳汇还是净碳源，并首次将生物多样性纳入加拿大森林系统环境变化情景下的碳固存增强倡议。通过增加我们对土壤生物多样性与土壤碳、氮循环相关过程的了解，这项研究将有助于确定如何减轻环境变化的影响，并维持森林土壤系统的生态系统功能。我实验室的研究广泛涉及社区生态学、生态系统生态学和应用陆地保护等领域。

The loss of biodiversity is the greatest threat facing ecosystem health in the world today. Many ecosystems are currently undergoing dramatic changes in biodiversity due to habitat loss and fragmentation associated with land use change, pollution, overexploitation, and climate change. My research will provide the science necessary to help mitigate this loss by uncovering the drivers of biodiversity loss, and the consequences of loss on ecosystem processes and functioning. As there is unequivocal evidence linking the effects of global change, soil biodiversity and nutrient cycling, my research uses a terrestrial-detrital system to experimentally study the regulation and functional significance of biodiversity in the context of global change, specifically with respect to carbon sequestration and nitrogen dynamics in forest soils. I use two approaches to obtain accurate assessment of soil biodiversity, calculate rates of biologically mediated processes, and measure ecosystem function by way of detailed nutrient analysis; a food-web approach to understand the interactions among species within the community, and a mass-balance approach to account for nutrients and energy as they move through the food web. Over the next five years, my lab will develop long-term field sites in the Boreal forest and create meso-ecosystems under controlled laboratory conditions to isolate the ecological mechanisms that drive the relationships between global change, biodiversity and nutrient cycling. This program will address how changes in biodiversity equate to changes in ecosystem-level processes, if these changes dictate whether the system becomes a net carbon sink or a net carbon source, and is the first to incorporate biodiversity into designing carbon sequestration enhancement initiatives under environmental change scenarios for Canadian forest systems. By increasing our understanding of soil biodiversity-mediated processes associated with soil carbon and nitrogen cycles, this research will help identify how to mitigate the impacts of environmental change and maintain ecosystem function in forest soil systems. Research in my lab broadly spans the areas of community ecology, ecosystem ecology, and applied terrestrial conservation.