高寒沙地高山柳灌丛C、N、P生态化学计量变化特征及其与微生物群落演替耦合关系研究

In recent decades，the desertification is serious in Northwest Sichuan alpine-cold grassland by reason of global climate change and over grazing. Ecological restoration is one of the effective measures to repair desertification. At present, researches of the temporal and spatial variation of nutrient elements ecological stoichiometry and microbial community succession in the process of ecological restoration are lacking. And the internal relations and mechanism of action between nutrient elements ecological stoichiometry and microbial community succession was still unclear. Salix cupularis, a species native to northwest Sichuan, has been characterized as a kind of sand fixation plant. In this study, based on the method of space instead of time , the accumulation, temporal and spatial distribution patterns and ecological stoichiometry of carbon(C), nitrogen(N) and phosphorus(P) in different plantation ages bushwood ecosystems of Salix cupularis were studies by sampling analysis of plant and soil. And the the spatial and temporal variation characteristics of microbial community succession were investgated by using metagenomics techniques. We investigate the influence of C, N and P ecological stoichiometry on microbial succession, and then analyze the coupling relationship between the change of C, N and P and succession of functional microbiome in Salix cupularis bushwood ecosystem. Results of this study will help to (1) understand the mechanisms and the inner relationship between C, N and P ecological stoichiometry and microbial succession in bushwood ecosystem, (2) explore various microbial mechanisms in response to changes in ecosystem C, N and P ecological stoichiometry and the relative importance of these mechanisms; (3) provide a scientific basis for improving effectiveness and efficiency in the process of the ecological restoration.

川西北高寒草地沙化形势严峻，生态修复是沙漠化治理的有效措施。研究生态修复过程生态系统营养元素的生态化学计量时空变化和微生物群落演替规律的报道较少，生态系统演替过程中营养元素积累、迁移转化、生态化学计量变化与微生物群落演替的内在联系和作用机制尚不清楚。本项目以空间代时间的方法，野外采样分析与原位模拟实验相结合，利用宏基因组学等技术，研究和揭示川西北高寒沙地不同年限固沙植物高山柳灌丛生态系统植物-土壤-微生物C、N、P积累、空间分配格局和生态化学计量时空变化特征；研究土壤微生物群落结构和功能多样性的时空变化特征及其与生态系统C、N、P积累、空间分配格局及生态化学计量变化的耦合关系，阐明生态系统C、N、P生态化学计量关系变化与微生物群落演替之间的内在联系和作用机制，为揭示生态系统物质地球化学循环过程及其微生物机制，沙化土地生态修复措施和过程的调控，提高修复效果和效率提供科学依据。

川西北高寒草地沙化形势严峻，生态修复是沙漠化治理的有效措施。研究生态修复过程生态系统营养元素的生态化学计量时空变化和微生物群落演替规律的报道较少，生态系统演替过程中营养元素积累、迁移转化、生态化学计量变化与微生物群落演替的内在联系和作用机制尚不清楚。本项目以空间代时间的方法，野外采样分析与原位模拟实验相结合，利用高通量测序学等技术，研究和揭示川西北高寒沙地不同年限固沙植物高山柳灌丛生态系统植物-土壤-微生物C、N、P积累、空间分配格局和生态化学计量时空变化特征；研究土壤微生物群落结构和功能多样性的时空变化特征及其与生态系统C、N、P积累、空间分配格局及生态化学计量变化的耦合关系，阐明生态系统C、N、P生态化学计量关系变化与微生物群落演替之间的内在联系和作用机制，为揭示生态系统物质地球化学循环过程及其微生物机制，沙化土地生态修复措施和过程的调控，提高修复效果和效率提供科学依据。