耕作方式对农田土壤微生物功能多样性的影响

通过种植前对土壤进行不同耕作处理试验，探讨不同耕作方式对土壤微生物群落代谢功能多样性的影响。采用Biolog-ECO微平板检测法，研究了撂荒、翻耕、免耕和旋耕4种不同耕作方式下土壤微生物碳源代谢的多样性变化特征。结果表明：在168 h培养期内，撂荒和免耕处理下AWCD值明显高于翻耕和旋耕处理；免耕条件下微生物功能多样性指数、优势度指数和丰富度指数与撂荒条件相似，而进行翻耕和旋耕后，三指标均显著下降。土壤微生物群落主成分分析和聚类分析结果显示，免耕条件下，土壤微生物具有接近于撂荒处理的碳源代谢模式和代谢能力，翻耕和旋耕则差异较大。分析试验结果，不同耕作方式对土壤微生物群落代谢和功能多样性产生较显著影响，免耕对其具有较好的保护作用。

Effects of Different Tillage Modes on Metabolic Functional Diversity of Soil Microbial Community

The effects of different tillage modes on soil microbe functional diversity were evaluated in this paper through different tillage test on soil before planting. The soil microbial metabolism diversity in four tillage modes including abandoned, tilled, no-tillage and rotary were examined by the method of Biolog ECO-micro plate culture．The result showed that within 168 h of culture, the average well color development (AWCD) was obviously higher in no-tillage than in the tilled mode. The functional diversity, dominance and richness index of soil microbes in no-tillage and abandoned were incredibly similar, when they fell significantly in tilled and rotary treatments. The result of PCA and cluster analysis demonstrated that the carbon source metabolic pattern and ability of the soil microbes in no-tillage was similar to that in abandoned, while it had a significant alteration in tilled and rotary. Different tillage modes could affect the metabolic and functional diversity of soil microbial communities significantly; no-tillage had better protective effect than other tillage modes.