耕作方式与绿肥种植对土壤微生物组成和多样性的影响

摘要

通过田间定位试验研究了免耕与绿肥种植技术配合使用对土壤微生物组成和多样性的影响.结果表明,免耕对土壤微生物的影响明显小于绿肥种植,免耕和绿肥种植(ZG)处理细菌与真菌拷贝数比值为2.51×103,显著高于免耕+不种绿肥(ZT)和常规耕作+不种绿肥(CT)处理.不同处理细菌相对含量及组成发生了一定变化,但优势微生物均为变形菌门(Proteobacteria)、绿弯菌门(Chloroflexi)和酸杆菌门(Acidobacteria),微生物多样性(Shannon指数和Simpson指数)和丰富度(ACE指数和Chao l指数)差异不显著.相关性分析表明土壤结构、土壤营养物质含量和土壤pH值均在一定程度上决定了土壤微生物组成.%A long-term stationary field experiment was carried out to study effect of zero-tillage (ZT) and/or cultivation of green manure crops (CGMC) on composition and diversity of soil microbial community.Results show that ZT affected soil microbes less significantly than CGMC did;ZT plus CGMC was significantly higher than ZT and CT (conventional tillage) and the former had a ratio of copy numbers of bacteria and fungi being 2.51 × 103.Bacteria in the soils varied somewhat in relative population and composition relative to treatment,but remained to be dominated by with Proteobacteria,Chloroflexi and Acidobacteria and almost the same in diversity of soil microbial community (Shannon index and Simpson index) abundance (ACE and Chao 1) in all the treatments.Correlation analysis shows that to a certain extent,soil structure,contents of soil nutrients and soil pH determine soil microbial composition.