Abstract: It is important to evaluate the effect of organic fertilizer application on the recovery of degraded grassland from the perspective of soil microbial community structure. The paper investigated the responses of soil microbial community structure,diversity,and function to the application of organic fertilizer using high-throughput sequencing technology in a light to moderately degraded alpine grassland around Qinghai Lake. The results showed that:Organic fertilizer treatment increased OTUs of bacteria and decreased OTUs of fungi;Organic fertilizer application changed the composition and relative abundance of soil bacterial and fungal communities,;among the constituent species of the bacterial community at the genus level,it also changed the community structure;Application of organic fertilizer appropriately increased the Richness index of the soil bacterial community and decreased the Richness index of the fungal community,while decreasing the Chao1 index of the bacterial community,but increasing the Chao1 index of the fungal community. Chao1 index and decreased Shannon and Pielou indices for both bacterial and fungal communities;Gamma-proteobacteria was the indicator species for soil bacteria after organic fertilizer application treatment;Dothideomycetes were the indicator species for soil fungi. The application of organic fertilizer promoted the recovery of beneficial soil microorganisms and improved the soil microbiota.

Key words: Organic fertilizer, Microflora, Microbial community structure and diversity, Indicator species, Degraded alpine grassland

摘要： 从土壤微生物群落结构与多样性角度评价施用有机肥对退化草地的恢复效果，论文以环青海湖地区的轻度-中度退化高寒草地为研究对象，采用高通量测序技术研究了土壤微生物群落结构、多样性及功能类群对施用有机肥的响应特征。结果表明：施有机肥处理增加了细菌的OTUs，降低了真菌的OTUs；施有机肥改变了土壤细菌与真菌群落组成及相对丰度；在属水平上细菌群落的组成种类中，Gaiella在施肥处理时丰度最高，同时也改变了群落结构；施有机肥能适当增加土壤细菌群落的Richness指数，降低了真菌群落的Richness指数，而降低了细菌群落的Chao1指数，但增加了真菌群落的Chao1指数，细菌和真菌群落的Shannon和Pielou指数都降低；施有机肥处理后Gammaproteobacteria是土壤细菌的指示物种，Dothideomycetes是土壤真菌的指示物种，施用有机肥后促进土壤有益微生物的恢复，改善土壤微生物区系。

关键词: 有机肥, 微生物区系, 微生物群落结构及多样性, 指示物种, 退化高寒草地