Microbial diversity and function in forest soils and the influence of rhizosphere carbon flow

林业在加拿大的经济繁荣中起着至关重要的作用，加拿大近一半的陆地被森林覆盖，世界上10%的森林在加拿大境内。在不列颠哥伦比亚省，林业是主要产业，全省有56%的森林。此外，森林对于缓和气候、过滤空气和水以及作为娱乐场所至关重要。越来越强调可持续森林管理，平衡资源开采与保持生态系统服务和生物多样性。为了提供合理决策的基础，森林管理者必须充分了解森林如何运作以及森林管理如何影响森林运作。营养循环和吸收已被证明是森林生态系统健康的关键过程。土壤微生物群落通过土壤有机质的分解和无机养分和矿物质的周转，在土壤养分循环过程中发挥关键作用，从而影响森林生产力。尽管人们认识到土壤微生物群落在树木养分获取中的重要性，但我们对土壤微生物的多样性、它们的功能作用以及影响微生物群落大小、结构和活动的因素知之甚少。制定这些系统的管理策略需要了解调节土壤养分循环的过程以及各种管理实践对这些过程的影响。本研究项目采用多种新颖的分子和生化方法，结合稳定同位素标记方法来识别重要的微生物，阐明它们在土壤过程中的作用，如养分循环和碳的储存或释放，并阐明它们与植物根系相互作用的方式。这将有助于更好地理解生态系统的功能。

Forestry has a critical role in Canada's economic prosperity with nearly half Canada's landmass being forested and 10% of the world's forests being within Canada. In British Columbia forestry is the key industry with 56% of BC being forested. In addition, forests are vital for moderating climate and filtering air and water and as places of recreation. There is increasing emphasis on sustainable forest management, balancing resource extraction with retention of ecosystem services and biodiversity. In order to provide a basis for rational decisions forest managers must have sufficient knowledge about how forests function and how their management affects that functioning. Nutrient cycling and uptake have been shown to be critical processes for the health of forest ecosystems. The soil microbial community has a key role in nutrient cycling processes in soil through decomposition of soil organic matter and turnover of inorganic nutrients and minerals and, therefore, forest productivity. Despite the recognised importance of the soil microbial community in nutrient acquisition for trees we know very little about the diversity of microorganisms in soil, what their functional roles are and what factors influence the size, the structure and the activity of the microbial community. Developing management strategies for these systems requires an understanding of the processes regulating soil nutrient cycling and the impact of various management practices on these processes. This research program uses a variety of novel molecular and biochemical methods coupled with stable isotope labeling approaches to identify the important micro-organisms, elucidate their role in soil processes such as nutrient cycling and the storage or release of carbon, and clarify the manner in which they interact with plant roots. This will result in a better understanding of ecosystem functioning.