Effects of typical plant on soil microbial communities in an Inner Mongolia grassland

Abstract

Aims Vegetation in Inner Mongolia grassland has changed due to overgrazing and climate change. Our objective was to explore the effects of plant species on soil microbial communities in an Inner Mongolia grassland to understand the ecological consequences of vegetation changes in this region. Methods We investigated the sizes and community structures of bacteria and fungi in the rhizosphere and non-rhizosphere soils of several typical plant species in a degradation-restoration site in Xilin Gol Grassland using real-time PCR and terminal restriction fragment length polymorphism (T-RFLP) analysis. Important findings Different plant species have significant effects on the sizes of bacterial communities in both rhizosphere and non-rhizosphere soils and size of fungal communities in rhizosphere soil. The abundances of bac- teria and fungi in the rhizosphere soil were generally higher than those in non-rhizosphere soils, particularly for fungi. Multi-response permutation procedures and principal component analysis of T-RFLP data showed sig- nificant differences of the bacterial and fungal community structure between rhizosphere and non-rhizosphere soil for most species, and the fungal community structures of all samples can be divided into the rhizosphere and non-rhizosphere soils. In addition, the community structure clustered by plant species is more evident for bacteria. These results revealed important effects of plant species on microbial community composition as well as significant differences of microbial community between rhizosphere and non-rhizosphere soils. Findings are helpful for understanding plants-soil-microbe interactions and mechanisms involved in the Inner Mongolia grassland region.