Slope aspect influences plant biomass, soil properties and microbial composition in alpine meadow on the Qinghai-Tibetan Plateau

Abstract

Difference in soil moisture, temperature and microclimate on sunny and shady slope aspect can lead to various plant community, sequentially modify soil microbial community. In this study, we measured soil properties including soil temperature, soil moisture, soil organic carbon (SOC), total nitrogen (TN); plant properties including aboveground and underground biomass, and microbial properties including microbial carbon (C), nitrogen (N) content and phospholipid fatty acids (PLFAs) to evaluate the effects of slope aspect on plant biomass, soil properties and microbial community in the alpine meadow on the Qinghai–Tibetan Plateau. The results showed that sunny sites had higher soil temperature, organic C and underground biomass (UB), while shady sites had higher soil moisture, TN and aboveground biomass (AB). Principal component analysis (PCA) indicated that bacteria were the dominant soil microbes at sunny sites, while the fungi was more abundant at sites with a shady aspect. Redundancy analysis (RDA) showed that temperature was the major factor affecting the composition of the microbial community. It can be concluded, that slope aspect can significantly alter microbial composition due to the differences in plant community, soil properties and especially environmental factors.