van der Heijden Marcel G A, Bardgett Richard D, van Straalen Nico M
Department of Animal Ecology, Faculty of Earth and Life Sciences, Institute of Ecological Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
Ecol Lett. 2008 Mar;11(3):296-310. doi: 10.1111/j.1461-0248.2007.01139.x. Epub 2007 Nov 29.
Microbes are the unseen majority in soil and comprise a large portion of life's genetic diversity. Despite their abundance, the impact of soil microbes on ecosystem processes is still poorly understood. Here we explore the various roles that soil microbes play in terrestrial ecosystems with special emphasis on their contribution to plant productivity and diversity. Soil microbes are important regulators of plant productivity, especially in nutrient poor ecosystems where plant symbionts are responsible for the acquisition of limiting nutrients. Mycorrhizal fungi and nitrogen-fixing bacteria are responsible for c. 5-20% (grassland and savannah) to 80% (temperate and boreal forests) of all nitrogen, and up to 75% of phosphorus, that is acquired by plants annually. Free-living microbes also strongly regulate plant productivity, through the mineralization of, and competition for, nutrients that sustain plant productivity. Soil microbes, including microbial pathogens, are also important regulators of plant community dynamics and plant diversity, determining plant abundance and, in some cases, facilitating invasion by exotic plants. Conservative estimates suggest that c. 20 000 plant species are completely dependent on microbial symbionts for growth and survival pointing to the importance of soil microbes as regulators of plant species richness on Earth. Overall, this review shows that soil microbes must be considered as important drivers of plant diversity and productivity in terrestrial ecosystems.
微生物是土壤中肉眼看不见的主体，并且构成了生命遗传多样性的很大一部分。尽管它们数量众多，但土壤微生物对生态系统过程的影响仍知之甚少。在这里，我们探讨土壤微生物在陆地生态系统中所起的各种作用，特别强调它们对植物生产力和多样性的贡献。土壤微生物是植物生产力的重要调节者，尤其是在养分贫瘠的生态系统中，植物共生体负责获取限制性养分。菌根真菌和固氮细菌每年为植物获取的氮占总量的约5%至20%（草原和热带稀树草原）至80%（温带和北方森林），磷占总量的比例高达75%。自由生活的微生物也通过维持植物生产力的养分矿化和竞争，强烈调节植物生产力。土壤微生物，包括微生物病原体，也是植物群落动态和植物多样性的重要调节者，决定着植物的丰度，在某些情况下，还促进外来植物的入侵。保守估计表明，约20000种植物的生长和存活完全依赖于微生物共生体，这表明土壤微生物作为地球上植物物种丰富度调节者的重要性。总体而言，本综述表明，土壤微生物必须被视为陆地生态系统中植物多样性和生产力的重要驱动因素。
