保护性耕作下黄土高原作物轮作系统土壤健康评价  

The evaluation of soil properties under conservation tillage in a maize-wheat-soybean rotation on the Loess Plateau

作　　者：王明明[1] 李峻成[1] 沈禹颖[1] 

机构地区：[1]兰州大学草地农业科技学院农业部草地农业生态系统学重点开放实验室,甘肃兰州730020

出　　处：《草业科学》2011年第6期882-886,共5页Pratacultural Science

基　　金：国家重点基础研究发展规划(2007CB106804;G2000018602);澳大利亚国际农业研究中心项目(LWR21999/094);教育部2003年重点科技项目

摘　　要：在黄土高原雨养农业区,以4个耕作处理[传统耕作（t）、传统耕作＋秸秆覆盖（ts）、免耕（nt）和免耕＋秸秆覆盖（nts）]的2年3熟粮豆轮作系统为对象,研究了0~5和5~10 cm土壤全碳、有机碳、全氮及微生物生物量碳和氮等指标的变化特征。结果表明,实施保护性耕作7年后,有机碳含量在ts、nt和nts处理下比t处理显著增加22.9%、25.3%和42.6%,0~5 cm层土壤微生物生物量碳和氮含量均以nts最高,t处理最低。在0~10 cm土层内,免耕促进了土壤碳的表聚化,但耕作有助于秸秆有机碳在土壤剖面的均匀分布。研究结果表明,短期尺度下微生物量碳和氮是反映耕作措施的敏感指标,中期尺度下土壤有机碳可以敏感反映土壤健康状况。The aim of this study was to determine how soil properties changed when conservation tillage was used in a maize-wheat-soybean rotation on the Loess Plateau,China.The four tillage treatments were： t（conventional tillage）,ts（conventional tillage with stubble retention）,nt（no tillage） and nts（no tillage with stubble retention）.Soil total C,organic C,total N and microbial biomass C and N in the 0-5 cm and the 5-10 cm layer was measured over a seven year period in each treatment.Soil organic C was significantly higher in the ts,nt and nts treatments,compared with that in the t treatment.Soil microbial biomass C and N in 0-5 cm layer was highest in the nts treatment among the treatment..No-till enhanced soil organic C accumulation in the top layer,tillage incorporated stubble distribution along the soil profile.The results showed that soil microbial biomass C was an indicator for short term run effects of conservation tillage,and soil organic C was an indicator for mid term run conservation tillage.

关 键 词：土壤全碳 土壤全氮 土壤有机碳 土壤微生物量碳氮 

分 类 号：S158.2[农业科学—土壤学]