长期秸秆还田对稻田土壤真菌群落结构的影响

Effects of long-term straw return on soil fungal community structure in paddy field

长期秸秆还田可以为土壤输入丰富的营养元素.通过探究不同的秸秆还田量对稻田土壤理化性质和真菌多样性的影响,为合理利用作物秸秆提供科学依据.试验设置4个不同处理,即秸秆不还田(S0)、秸秆半量还田(S1)、秸秆全量还田(S2)、1.5倍秸秆还田(S3),于水稻收获后取0~20 cm土壤样品,用于真菌群落结构分析及土壤养分测定.结果显示,与S0相比,在不同处理间pH无差异;全磷、速效磷、铵态氮质量比提高.较S0相比,其他秸秆还田处理均显著提高了真菌的Chao1指数和ACE指数.秸秆处理使真菌群落结构明显改变.在群落组成方面,秸秆还田后的土壤中子囊菌门、粪壳菌纲的相对丰度等较S0处理分别增加了8.11%~25.31%和21.63%~39.23%,肉座菌目丰度降低了44.92%~48.25%.冗余分析表明,真菌群落主要受到全磷、速效磷和硝态氮的影响.研究表明,通过适量的添加秸秆,土壤中全磷、速效磷等的含量显著提高.秸秆还田造成了稻田土壤真菌群落结构的改变,RDA和相关性分析表明,全磷、速效磷、硝态氮对真菌群落的结构影响显著.

Long-term straw return can input abundant nutrients into the soil.By exploring the effects of different amounts of straw return on the physicochemical properties and fungal diversity of paddy soil,we aim to provide scientific evidence for the rational utilization of crop straw.The experiment set up four different treatments:no straw return(S0),half straw return(S1),full straw return(S2),and 1.5 times straw return(S3).Soil samples were taken from the 0−20 cm layer after rice harvest for fungal community structure analysis and soil nutrient determination.The results showed that there were no differences in pH between the different treatments compared to S0.However,the mass ratios of total phosphorus,available phosphorus,and ammonium nitrogen increased.Compared to S0,the other straw return treatments significantly increased the fungal Chao1 index and ACE index.Straw treatments caused significant changes in fungal community structure.Regarding community composition,the relative abundances of Ascomycota and Sordariomycetes in soils with straw return increased by 8.11%to 25.31%and 21.63%to 39.23%,respectively,compared to S0,while the abundance of Hypocreales decreased by 44.92%to 48.25%.Redundancy analysis indicated that the fungal community was mainly influenced by total phosphorus,available phosphorus,and nitrate nitrogen.This study demonstrates that adding an appropriate amount of straw significantly increases the content of total phosphorus and available phosphorus in the soil.Straw return altered the fungal community structure in paddy soil,with RDA and correlation analysis showing that total phosphorus,available phosphorus,and nitrate nitrogen significantly affected the structure of the fungal community.