秸秆与紫云英覆盖对土壤-微生物-甘薯植株生态化学计量特征的影响  

Effects of straw and milk vetch mulching on the ecological stoichiometric characteristics of soil-microbe-sweet potato plants

作　　者：李绍兴 宋稳锋 周玉玲 宋李霞 任可 马群 王龙昌 LI Shao-xing;SONG Wen-feng;ZHOU Yu-ling;SONG Li-xia;REN Ke;MA Qun;WANG Long-chang(College of Agronomy and Biotechnology,Southwest University,Engineering Research Center of South Upland Agriculture,Ministry of Education,Chongqing 400715,China)

机构地区：[1]西南大学农学与生物科技学院,南方山地农业教育部工程研究中心,重庆400715

出　　处：《草业学报》2025年第3期56-70,共15页Acta Prataculturae Sinica

基　　金：国家自然科学基金项目(31871583)资助。

摘　　要：针对西南旱作农业区水土流失、耕地质量低下等问题,亟须探索农业可持续耕作措施,缓解养分限制。以西南地区“蚕豆/玉米/甘薯”旱三熟套作模式中的甘薯田为研究对象,作物前茬秸秆作为覆盖还田材料,设置4个处理:无覆盖(CK)、秸秆覆盖(S)、秸秆+紫云英覆盖(S+M)、紫云英覆盖(M),通过对土壤-微生物-甘薯植株碳、氮、磷含量、生态化学计量特征以及内稳性指数的研究,揭示秸秆和紫云英覆盖对土壤养分限制及生态化学计量特征的影响规律。结果表明:1)秸秆与紫云英覆盖处理显著提高土壤有机碳和全氮含量,从土壤化学计量比的变化发现覆盖处理能有效缓解当地土壤养分限制。2)秸秆与紫云英覆盖处理显著提高了土壤微生物量碳、氮和磷含量,不同生育时期微生物化学计量比有所差异,生育前期波动较大,中后期相对稳定。内稳性特征方面,除CK处理外,微生物与土壤化学计量比之间呈现出严格的内稳性特征。3)秸秆与紫云英覆盖处理显著提高了甘薯各器官氮含量,其中以秸秆与紫云英协同覆盖处理效果最佳。甘薯产量表现为S+M>S>M>CK。化学计量比方面,S+M处理有利于延长甘薯生长时间,有效缓解养分限制状况。甘薯植株各器官化学计量比在整个生育期内均表现为严格的稳态。综上所述,在西南旱作农业区通过进行秸秆与紫云英覆盖,可以提升甘薯产量,调节土壤养分限制,土壤与微生物化学计量比均保持严格的内稳态。There is an urgent need to explore sustainable agricultural cultivation measures and alleviate nutrient limitations as a response to the problems of soil erosion and low quality of cultivated land in the dry-farming areas of southwest China.This study focused on sweet potato plantings within a“fava bean(Vicia faba)/corn(Zea mays)/sweet potato(Ipomoea batatas)”rain-fed three-crop rotation pattern in southwest China.Four treatments were set up:no mulching(CK),straw mulching(S),straw and milk vetch(Astragalus sinicus)mulching(S+M)and milk vetch mulching(M).By studying the content of carbon,nitrogen and phosphorus,ecological stoichiometric characteristics and the homeostasis index of the soil-microbe-sweet potato plant stoichiometric data,the effects of straw and milk vetch mulching cover on soil nutrient restriction and ecological stoichiometric characteristics were explored.It was found that:1)The straw and milk vetch mulching treatments significantly increased soil organic carbon and total nitrogen content,and from changes in the soil stoichiometric ratio,it was deduced that the mulching treatments effectively alleviated soil nutrient restriction.2)The straw and milk vetch mulching treatments significantly increased the content of soil microbial biomass carbon,nitrogen and phosphorus,and showed differences in the C-N-P stoichiometric ratios of microorganisms at different crop growth stages,with large fluctuations in the early growth period,and relatively stable values in the middle and late growth period.In terms of homoeostasis characteristics,except for the CK treatment,the microbial and soil stoichiometric ratios showed strong homoeostasis.3)The nitrogen content of sweet potato organs was significantly increased by straw and milk vetch mulching treatments,and the best effect was achieved in the S+M mulching treatment.The yields of sweet potato were ranked S+M>S>M>CK.In terms of stoichiometric ratio,S+M treatment was superior.This treatment prolonged the growth time of sweet potato,and effectively alleviated

关 键 词：秸秆覆盖 紫云英覆盖 甘薯 化学计量特征 内稳性 

分 类 号：S154.4[农业科学—土壤学]