节点文献
秸秆还田量和类型对土壤氮及氮组分构成的影响
Effects of straw returning amount and type on soil nitrogen and its composition
【摘要】 秸秆还田可以补充作物生长所需的营养元素,也是提升土壤质量、构建肥沃耕层的关键措施.为揭示长期稻麦秸秆还田对土壤氮组分变化的影响,选取了江苏太湖地区稻田土壤为研究对象,设置了稻麦秸秆均不还田(NRW)、麦秆还田+稻秆不还田(W)、稻秆还田+麦秆不还田(R)、稻麦秸秆均半量还田(HRW)和稻麦秸秆均全量还田(ARW)共5个处理,研究秸秆还田量和秸秆类型对土壤全氮及氮组分构成变化的影响.结果表明:与2007年相比,2017年除NRW处理外,其他处理土壤全氮和重组氮都增加,稻秆还田处理土壤全氮和重组氮含量最高;所有处理土壤轻组分有机质中氮含量都下降,ARW处理土壤轻组分有机质中氮含量下降最多,为8.09 g·kg-1;各处理间碱解氮没有明显差异;秸秆还田处理10年后,稻秆还田处理硝态氮和铵态氮含量均最高.秸秆是土壤氮素的重要物质来源,增加效果取决于秸秆类型和还田量.轻组分有机质中的氮含量变化对秸秆还田反应更敏感,重组氮相对稳定,是维持土壤肥力的关键组分,随着秸秆还田时间的延长,土壤全氮与氮组分之间的相关关系发生变化.稻秆全量还田+麦秆不还田更有利于提升土壤氮素水平.
【Abstract】 Straw returning to soil can supplement soil nutrients required for crop growth, fertilize soil, and improve soil quality. To explore the long-term effect of straw returning on soil total nitrogen and its composition, herein, five treatments including no rice straw + no wheat straw returning(NRW), no rice straw + all wheat straw returning(W), all rice straw + no wheat straw returning(R), half rice straw + half wheat straw returning(HRW), and all rice straw + all wheat straw returning(ARW) were conducted in triplicate in Taihu Lake region, China. The effects of both straw amount and type were examined. Compared with the results obtained in 2007, the results herein obtained in 2017 showed that after 10 years of straw returning, soil total nitrogen and heavy fraction nitrogen increased, while light fraction organic matter decreased. Among the five treatments, ARW had the largest decrease in light fraction nitrogen of 8.09 g·kg-1; the R treatment had the highest contents of both total and heavy fraction nitrogen, and also the highest contents of ammonium and nitrate. There was no significant difference in alkali-hydrolyzable nitrogen among the five treatments. These results indicated that crop straw was the critical material source for soil nitrogen, and that the effects of straw returning on soil nitrogen depended on the type and amount of crop straw returned to soil. The changes of light fraction nitrogen were more sensitive to straw returning, while the heavy fraction nitrogen was relatively stable, which was the key fraction sustaining soil fertility. With the prolonging of straw returning, the relationship between the total nitrogen and diffe-rent nitrogen components changed. The processing manner of all rice straw returning + no wheat straw returning was the way that could most significantly enhance soil nitrogen content.
【Key words】 straw returning; light and heavy fraction; ammonium nitrogen; nitrate nitrogen;
- 【文献出处】 应用生态学报 ,Chinese Journal of Applied Ecology , 编辑部邮箱 ,2019年04期
- 【分类号】S141.4;S153.6
- 【网络出版时间】2019-02-22 11:22
- 【被引频次】51
- 【下载频次】1353