朱建彬 郭相平 谢毅 陈盛 曹克文 王易天

摘要： 利用田间试验，探究了秸秆隔层还田及水氮管理对隔层以上土壤团聚体及有机碳含量的影响。结果表明：①埋设秸秆隔层、90%田间最大持率灌水上限及225 kg/hm2氮素用量均显著提高土壤大团聚体含量及稳定性。②秸秆隔层还田配合高水高氮处理土壤有机碳含量最高，秸秆隔层还田且水、氮用量较低处理的土壤有机碳含量与水、氮用量较高但未秸秆隔层还田处理间无显著差别。③随着土壤团聚体粒径增大其有机碳含量增加，2.000～0.251 mm团聚体对土壤有机碳贡献率最高。埋设秸秆隔层、90%θf灌水上限及225 kg/hm2氮素用量更有利于土壤大团聚体的形成，提高团聚体稳定性，增加土壤有机碳含量。

关键词： 秸秆隔层;水氮管理;土壤团聚体;有机碳;有机碳贡献率

中图分类号： S625.5+4 文献标识码： A 文章编号： 1000-4440（2021）03-0632-07

Effects of returning straw interlayer to the field， water and nitrogen management on aggregates and carbon sequestration of facility soil

ZHU Jian-bin， GUO Xiang-ping， XIE Yi， CHEN Sheng， CAO Ke-wen， WANG Yi-tian

（College of Agricultural Science and Engineering， Hohai University， Nanjing 210098， China）

Abstract： Effects of interlayer straw returning to the field， water and nitrogen management on soil aggregates and organic carbon content above the interlayer were explored using field experiments. The results showed that， firstly， the content and stability of big soil aggregates were significantly increased under the treatments of burying straw interlayer， 90% θf irrigation upper limit and 225 kg/hm2 nitrogen dosage. Secondly， under the treatment of straw interlayer burying combined with high water and high nitrogen contents， the soil organic carbon content was the highest. The soil organic carbon content between straw interlayer burying and lower water， nitrogen dosage treatment and higher water， nitrogen dosage without straw interlayer treatment showed no significant difference. Thirdly， as the diameter of soil aggregates increased， the organic carbon content increased， and aggregates with 2.000-0.251 mm diameters showed the highest contribution rate to soil organic carbon. Large soil aggregates are easy to form under the treatments of burying straw interlayer， 90%θf irrigation upper limit and 225 kg/hm2 nitrogen dosage， besides， the stability of aggregates is improved and soil organic carbon content is increased.

Key words： straw interlayer;water and nitrogen management;soil aggregates;organic carbon;contribution rate of organic carbon

秸稈富含有机质及植物生长所需营养元素，目前中国秸秆年产量已超过8×109 t[1]。研究发现，将秸秆浅埋入土壤一定深度形成秸秆隔层，配合使用滴灌技术，能有效减少秸秆隔层以上土壤水分及肥料的下渗，同时能抑制地下水蒸发以及由地下水引起的渍害[2]。目前关于传统秸秆还田对土壤团聚体及有机碳含量的影响研究较多，而鲜有浅埋秸秆隔层结合水氮管理对其影响的研究。本研究采用随机区组设计大田试验，将秸秆以隔层方式还田，配合水、氮管理，研究其对土壤团聚体及有机碳含量的影响，以期在设施蔬菜生产中为秸秆资源及水、氮资源的高效利用提供依据。……