重度放牧对荒漠草原土壤养分及微生物多样性的影响

Effects of Heavy Grazing on Soil Nutrients and Microbial Diversity in Desert Steppe

本研究以荒漠草原为研究对象,基于高通量基因组测序技术,分析土壤中微生物群落的多样性,并测定土壤理化指标,旨在探讨重度放牧对土壤养分和微生物多样性的影响。研究结果显示,重度放牧显著降低土壤含水量、有机质和有效磷的含量(P<0.05),显著增加土壤中的氮素含量(P<0.05);重度放牧对土壤真菌多样性没有显著差异,但显著降低土壤细菌的Simpson指数(P<0.05);荒漠草原土壤细菌群落的优势门类是放线菌门、酸杆菌门、变形菌门和芽单胞菌门,土壤真菌群落的优势门类是子囊菌门和担子菌门。可见,放牧对土壤养分有显著影响,对细菌群落的Simpson指数有显著影响,但对土壤真菌群落多样性无明显影响。

The diversity of microbial communities in soil was analyzed based on high-throughput genome sequencing technology in the present study.Integrated with soil physical and chemical parameters,effects of overgrazing on soil nutrient and microbial diversity were explored.The results showed that overgrazing significantly reduced soil water content,organic matter and available phosphorus(P<0.05).Overgrazing significantly increased nitrogen content in the soil(P<0.05).There was no significant difference in soil fungal diversity under overgrazing condition.However,the Simpson index of bacteria was significantly reduced in the soil due to overgrazing(P<0.05).The dominant species of bacterial community in desert steppe were actinomycetes,acid bacillus,proteobacteria and bacillus.The dominant species of soil fungal community were ascomycetes and burdens.It can be concluded that overgrazing had significant effects on soil nutrients and Simpson index of bacteria but not on soil microbial community diversity.