在室内模拟试验下，采用常规分析和高通量测序技术，研究了淹水培养30 d后，不同量小麦秸秆(0、10、20和50 g/kg)施用下两种类型的稻田土壤(高砂土和黄泥土)真菌群落多样性和组成的演替规律及其驱动因子。结果表明：秸秆还田显著降低了高砂土真菌群落多样性并改变了高砂土真菌群落组成，但不同量秸秆还田下，高砂土真菌群落组成并无显著性差异；而秸秆还田对黄泥土真菌群落多样性并无显著影响，与未施用秸秆相比，低秸秆施用量(10和20 g/kg)并未显著改变黄泥土中真菌群落组成，而当秸秆施用量为50 g/kg时，黄泥土真菌群落组成明显迁移。进一步的典范相关分析(CCA)发现，pH、EC和有机质(SOM)是影响秸秆还田后高砂土真菌群落迁移的重要因子，而pH、EC、SOM和碳氮比(C/N)是影响秸秆还田后黄泥土真菌群落迁移的主要调控因子。综合分析认为，秸秆还田主要通过改变土壤性质来调控真菌群落结构，而不同类型土壤的真菌群落多样性和组成对秸秆还田的响应不同。

Different amounts of wheat straws were incorporated into the two paddy soils (silty soil and clayed soil) to explore the impacts of straw return on the diversity and composition of fungal community after 30 days of flooding incubation based on conventional analysis and high-throughput sequencing. Results showed that straw addition significantly decreased the diversity of fungal community in the silty soil but not in the clayed soil. Compared to un-amended soils, straw addition changed fungal community composition in the silty soil, but no significant difference was found in fungal community compositions between different rates of straw amendment. Unlike to the silty soil, for the clayed soil, significant differences were found in soil fungal community compositions between un-amended soils and high rates of straw concentrations (50 g/kg), while no significant difference between un-amended soils and soils amended with low rates of straw concentrations (10 and 20 g/kg). pH, EC and SOM were identified by CCA analysis as variables that significantly contributed to the variance of fungal community in the silty soil, while pH, EC, SOM and C/N ratio as variables in the clayed soil. In conclusion, straw addition significantly changed fungal community composition by altering soil properties, and the response of soil fungal community composition to straw return depended on soil type.

S154.3

国家自然科学基金项目(41271308; 41601261)和公益性行业(农业)科研专项(201503136)资助。