Effects of Straw Returning on Soil Nutrients and Microbial Diversity in Cotton Field

【Objective】 To discuss the effects of straw returning on soil nutrients and microbial diversity in cotton field. 【Methods】 The degradation rate of cotton stalk was calculated by the weight change of cotton stalk. Soil nutrients such as organic matter content and physical and chemical properties of soil were determined. The number of cultivable microorganisms was measured by medium plate method. The effects of straw returning on soil microbial diversity were studied by high-throughput sequencing. 【Result】 The degradation rate of cotton straw could reach to 5.01%; The total amount of cultivable microorganisms increased by 9.8%, the number of bacteria increased by 64.6%, and the number of actinomycete increased by 39.3%; After returning straw, the contents of soil available nitrogen and available potassium increased significantly, which were 7.40% and 32.77%, respectively; High throughput sequencing data analysis showed that straw returning had an impact on microbial diversity, and the structure of the microbial flora, genus and species level changed obviously. 【Conclusion】 Straw returning can increase soil nutrients, increase the number of cultivable microorganisms and improve soil microbial diversity.