作为陆地生态系统的重要组成之一，土壤微生物在养分循环、凋落物分解和植物多样性维持等方面发挥着重要作用。前人的研究表明，土壤微生物的群落结构和多样性在小区或局部尺度上主要受植物物种组成和土壤属性的影响。但是，在较大的空间尺度上土壤微生物的功能多样性受哪些因素驱动我们了解很少。这对于评价土壤微生物群落如何响应全球变化及理解全球变化对陆地生态系统产生的潜在影响具有重要意义。
中科院华南植物园恢复生态学科研团队刘占锋博士与中国科学院生态环境研究中心、内蒙古呼伦贝尔环境研究所的专家合作，在内蒙古呼伦贝尔草原研究了区域尺度上土壤微生物功能多样性的驱动机制。研究人员发现，在区域尺度上植物群落结构和多样性不再是影响土壤微生物群落的重要驱动因子。在呼伦贝尔草原土壤微生物的功能多样性在区域尺度上主要受植被的生物量、土壤含水量和土壤N/P比值的影响。由于温带草原植被生物量主要受土壤水分和氮素的可获得性的限制，植被生物量可以很好地指示资源的可获得性。因此，该研究认为在温带草原土壤微生物的功能多样性在区域尺度上主要受资源的可获得性驱动。
该研究结果已发表在土壤科学研究领域权威杂志Soil Biology and Biochemistry 上。根据ScienceDirect的统计结果，该论文成为Soil Biology and Biochemistry杂志今年第一季度的25篇热点文章之一，该文章研究结果已被国内外同行所关注。(生物谷Bioon.net)
生物谷推荐原文出处：
Soil Biology and Biochemistry doi:10.1016/j.soilbio.2009.11.027
Plant biomass, soil water content and soil N:P ratio regulating soil microbial functional diversity in a temperate steppe: A regional scale study
Zhanfeng Liua, b, Bojie Fua, Xiaoxuan Zhenga and Guohua Liua, ,
Soil microorganisms are influenced by various abiotic and biotic factors at the field plot scale. Little is known, however, about the factors that determine soil microbial community functional diversity at a larger spatial scale. Here we conducted a regional scale study to assess the driving forces governing soil microbial community functional diversity in a temperate steppe of Hulunbeir, Inner Mongolia, northern China. Redundancy analysis and regression analysis were used to examine the relationships between soil microbial community properties and environmental variables. The results showed that the functional diversity of soil microbial communities was correlated with aboveground plant biomass, root biomass, soil water content and soil N: P ratio, suggesting that plant biomass, soil water availability and soil N availability were major determinants of soil microbial community functional diversity. Since plant biomass can indicate resource availability, which is mainly constrained by soil water availability and N availability in temperate steppes, we consider that soil microbial community functional diversity was mainly controlled by resource availability in temperate steppes at a regional scale.
