Association of soil bacterial diversity with plant community functional attributes in alpine meadows

Abstract

The interaction between plant diversity and soil physicochemical factors has been predicted to influence the variation in soil microbial diversity across space and time; however, only limited robust evidence has been found to support this prediction at broad scale. We examined the relationships between plant community functional attributes (i.e., community-weighted mean (CWM) and functional trait diversity (FD)) and soil microbial diversity in Tibetan alpine meadows under different environmental regimes. Soil bacterial diversity was weakly associated with plant species diversity but was significantly associated with both CWM and FD of five key functional traits, explaining nearly half of the variation in soil bacterial diversity. Soil bacterial diversity was positively associated with CWM and FD of plant height, leaf specific area, and leaf phosphorus but was negatively associated with CWM of leaf dry matter content. These results provide robust evidence supporting the theoretical prediction that the plant community functional attributes can explain variation in soil bacterial diversity. In addition, these results provide novel insights that could facilitate the understanding of the mechanisms of assembly of soil microbial diversity.