Soil Microbial Functional Diversity At Different Elevations In Alpine Meadows Of The Qinghai-Tibet Plateau

Microbial diversity plays critical roles in regulating multiple ecosystem functions and enhancing ecosystem stability.In this study,we investigated the functional diversity of the microbial community and its driving factors at six different elevation sites in Tibet by using Biolog microplate analysis and soil hydrolytic enzyme activity.The results showed that:(1)The carbon utilization of the soil microbial community and enzyme activity at different elevations of the alpine meadow increased gradually with culturing time.The principal component analysis showed that the elevation gradient significantly influenced the metabolism diversity of microbial community and enzyme activity.Polymer,carboxylic acids,and amino acids were the preferred carbon sources for the soil microorganisms.The utilization of carbohydrates,carboxylic acids,and amino acids was more sensitive than that of other carbon sources to changes in elevation.The carbon metabolic diversity and enzyme activity of soil microbial community showed a unimodal trend of first rise and then fall with the elevation rise.(2)The variation partitioning analysis showed that the soil,plant,and climate were the most important factors for explaining the carbon metabolism of the microbial community diversity and explained 79% of the variation.The partial mental test showed that the soil moisture,vegetation richness,and average annual precipitation were the most important environmental factors that influenced the variations in the utilization of microbial carbon sources at different elevations.The differentiation of soil hydrolase activity on the altitude gradient is significantly correlated with a variety of environmental factors,among which TN,SOC,soil moisture content,MAT and MAP are the key environmental factors leading to variation of soil hydrolase activity at different altitudes.In this study,the effects of different elevation gradient on the carbon metabolic diversity and soil enzyme activity of soil microbial community in alpine meadow of Qinghai-Tibet plateau were studied,and the main environmental factors affecting the carbon metabolic diversity and soil enzyme activity of soil microbial community were analyzed.It was found that the change of altitude gradient significantly affected the soil microorganism distribution,and the soil microorganism activity was highest in the central altitude area.Various environmental factors,including soil,plants and climate,can have important effects on soil microorganisms.Therefore,under the background of global climate change and alpine meadow degradation,our was expected to provide theoretical and scientific basis for soil quality monitoring,vegetation restoration and sustainable ecosystem management in the alpine meadow area of Qinghai-Tibet plateau.