Linkages between plant functional diversity soil biological communities and ecosystem services in agricultural grassland

人口的不断增长以及在不断变化的世界中生产粮食的相关需求是我们这一代人面临的最大挑战之一。显然，我们需要更明智地管理我们的农业系统，以便从生态系统服务中获益，包括生物多样性保护、碳和养分循环、温室气体监管以及沿着粮食生产。草地被认为是提供这些生态系统服务的一个关键系统，因为它们覆盖全球，而且还因为它们作为生物多样性和营养物质的储存库的潜力。例如，在英国，草原覆盖了36%的陆地表面，已经拥有英国土壤碳储量的32%，如果管理得当，它们可以储存更多。政府间气候变化专门委员会已经确定，如果管理得当，草原管理具有最大的潜力来封存额外的碳，因此草原是减缓气候变化的关键系统。在这里，我们建议，多种生态系统服务，如碳储存，养分保持和减少温室气体排放的草地可以通过管理的多样性和组成的植物群落。其原因是植物物种在功能特征或性状方面存在很大差异，这些差异强烈影响土壤有机输入的数量和质量，这反过来又刺激了负责土壤碳和氮循环的土壤微生物群落的成分。此外，这些特征的差异可能会改变生态系统服务的规模和方向，例如从温室气体净排放到通过植被管理减缓。本研究将分析与草地生物多样性恢复相关的关键草地植物物种的不同特性，并测试其对草地生态系统服务功能的影响，包括温室气体二氧化碳、甲烷和氧化亚氮的排放，土壤微生物活性以及养分循环和保持。这将提供关于植物多样性潜力的第一个信息，用于操纵土壤养分循环，以实现更大的碳和氮储存，并降低温室气体排放。

An increasing human population and the associated need to produce food in a changing world is one of the greatest challenge facing our generation. It is clear that we need to manage our agricultural systems more judiciously to yield benefits from ecosystem services, including biodiversity conservation, carbon and nutrient cycling and greenhouse gas regulation, along with food production. Grasslands are thought to be a key system for provision of these ecosystem services due to their large global coverage, but also because of their potential as reservoirs of biodiversity and nutrients. For instance, in the UK grasslands cover 36% of the land surface and already hold 32% of the UK soil carbon stock, and if managed correctly they could store even more. The Intergovernmental Panel on Climate Change have identified grassland management as having the greatest potential to sequester additional C if managed correctly, and so grasslands are a key system for climate change mitigation. Here we propose that multiple ecosystem services, such as carbon storage, nutrient retention and reduced greenhouse gas emissions in grassland can be enhanced with management of the diversity and composition of the plant community. The reason for this is that plant species differ greatly in their functional characteristics, or traits, and these differences strongly influence the amount and quality of organic inputs to the soil, which in turn stimulates components of the soil microbial community responsible for soil carbon and nitrogen cycling. Moreover, these differences in traits could change the magnitude and direction of ecosystem services such as from net emission of greenhouse gases, towards mitigation via vegetation management. In this study we will characterise the differing traits of key grassland plant species associated with grassland biodiversity restoration, and test their impact on grassland ecosystem services including emissions of the greenhouse gases carbon dioxide, methane and nitrous oxide, soil microbial activity and nutrient cycling and retention. This will provide the first information on the potential for plant diversity to be utilised to manipulate soil nutrient cycling towards greater carbon and nitrogen storage, and lower greenhouse gas emission.