冰川前沿裸露地可提供明确的时间序列，受人类扰动较少，是研究微生物原生演替的理想场所。在冰川前沿裸露地中氮是限制原生演替的一个主要因素，氮循环微生物在土壤氮的固定及对含氮化合物的分解和转化中起重要作用，而关于冰川前沿裸露地氮循环微生物群落演替及其响应环境变化的机理尚未开展系统研究。本项目拟沿祁连山从东向西降水梯度选择6条不同冰川前沿裸露地为研究地点，应用克隆文库和荧光定量PCR等现代分子生物学技术，研究不同演替年代、不同季节样品中氮循环微生物群落结构、多样性、功能基因表达量和氮循环相关酶活性，结合植被、土壤性质和环境气候变化，揭示冰川前沿裸露地氮循环微生物演替规律及其响应环境变化的机理。为冰川前沿裸露地微生物生态学研究提供科学资料。

Glacier foreland, with the chronosequence traits and less disturbances by human activities, is an ideal place to study primary succession. Nitrogen is known as one of the major limitation factors in primary succession. In glacier forelands, nitrogen biogeochemical cycling is mainly driven by microbial processes in nitrogen fixation, decomposition and transformation of nitrogen containing compounds. However, there is lack of systematic studies regarding the primary succession of the nitrogen cycling microorganisms in glacier forelands and how they response to environmental changes. The project intends to choose research sites in six different glacier forelands which along the Qilian Mountains from east to west with a precipitation gradient, apply clone library construction technique and Fluorescence quantitative PCR technique to study microbial diversity, community structures, functional genes expression and enzyme activity related to the nitrogen cycle. Combined with vegetation, soil properties, climate and environment change, the project will explore the mechanisms of nitrogen cycling microorganisms response to the environmental changes in the glacier to provide the scientific information for microbial ecology in the glacier foreland.