土壤中死亡微生物残留的rDNA和内转录间隔区（ITS）等分子标记会显著干扰微生物多度与多样性解析，但也为各微生物类群增殖和死亡动态的分析提供了新途径。探究残留DNA对微生物研究的影响和解析微生物类群动态均需明确残留DNA的类群特异性降解速率，然而相关研究仍十分匮乏。云南土壤丰富的微生物多样性为揭示残留DNA降解的类群特异性提供了研究条件。本项目拟利用已系统采集的云南典型土壤，结合引物标签添加、qPCR及高通量测序，建立残留DNA类群特异性降解速率的测定方法，揭示土壤微生物残留16S rDNA和ITS降解速率的类群特异性；通过土壤性质测定和水分、温度梯度培养实验明确其主要影响因素；结合微生物多度和多样性分析，阐明残留DNA类群特异性降解对土壤微生物研究的影响，并推算各微生物类群的增殖和死亡动态。研究结果有助于评估土壤微生物相关研究结论的准确性，还将为土壤各微生物类群动态的研究提供方法基础。

In soils, the relic rDNA and ITS from dead microbes can significantly obscure the examination of microbial abundance and diversity. However, they also provide a possibility for the analysis of taxon-specific microbial growth and mortality patterns. The determination of relic DNA taxon-specific degradation rates is essential to assess its influence on soil microbial studies and to analyze microbial taxon-specific dynamics, yet related research is still extremely scarce. Soil microbes in Yunnan province are highly diverse, which provides an ideal opportunity to reveal the taxon-specific degradation rates of soil microbial relic DNA. This project aims to establish a method for determining the taxon-specific degradation rates of microbial relic DNA, based on primer labeling, qPCR, and high-throughput sequencing, with the typical soils systematically collected across Yunnan province. Then, the taxon-specific degradation rates of microbial relic DNA will be examined, and their main influencing factors will be determined through soil property measurements, as well as moisture and temperature microcosmic experiments. Finally, the taxon-specific microbial growth and mortality patterns, as well as the influences of relic DNA on microbial community studies will be determined based on the examination of microbial abundance and diversity. The findings in this project will contribute to assessing the accuracy of related soil microbial studies, and provide a method foundation for the examination of soil microbial taxon-specific dynamics.