太湖地区水稻土不同粒级团聚体中酶活性对长期施肥的响应  

Responses of enzyme activities in different particle-size aggregates of paddy soil in Taihu Lake region of China to long-term fertilization

作　　者：牛文静[1] 李恋卿[1] 潘根兴[1] 宋祥云[1] 李志鹏[1] 刘晓雨[1] 刘永卓[1] 

机构地区：[1]南京农业大学农业资源与生态环境研究所,南京210095

出　　处：《应用生态学报》2009年第9期2181-2186,共6页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金面上项目(40771108)资助

摘　　要：以太湖地区水稻土长期肥料试验田为研究对象,采用低能量超声波物理分散法分离土壤团聚体,研究长期不同施肥处理下(化肥与秸秆配施、化肥与猪粪配施、单施化肥和不施肥)耕层土壤团聚体酶活性的变化.结果表明:供试土壤中200～2000μm和2～20μm粒组的团聚体占总土壤的60%～70%;施肥显著促进了200～2000μm团聚体的形成.各种酶活性在不同团聚体中的变化存在差异,脲酶和蔗糖酶在<2μm的粘粒组中活性最高,纤维素酶、多酚氧化酶和荧光素二乙酸酯(FDA)水解酶则以200～2000μm粗砂粒中活性最高.肥料的施用特别是化肥与有机肥的配合施用显著提高了200～2000μm粒组中蔗糖酶、脲酶、纤维素酶和FDA水解酶的活性.以5种酶活性的几何平均数(GMea)作为酶的综合活性指标,发现施肥处理下200～2000μm粒组中GMea显著高于其他粒组,可见大团聚体中土壤的酶活性对施肥措施响应敏感.有机和无机肥长期配合施用可以通过促进土壤团聚体的聚合和提高较大团聚体中酶活性来提高土壤整体的生物活性功能.Taking a long-term fertilized paddy soil in Taihu Lake region as research object, the en- zyme activities in 〈 2, 2-20, 20-200, and 200-2000μm aggregates under no fertilization （NF）, chemical fertilization （CF）, chemical fertilization plus straw return （CFS）, and chemical fertilization plus pig manure （CFM） were investigated. Fertilization promoted the formation of 200,2000 μm aggregates significantly. The enzyme activities differed with aggregates＇ particle-size. Urease and invertase activities were the highest in 〈 2μm aggregates, whereas the activities of cellulase, polyphenoloxidase and FDA hydrolase were the highest in 200-2000 μm aggregates, Fertilization, especially the combined fertilization of inorganic and organic fertilizers, increased the activities of urease, invertase, cellulase and FDA hydrolase in 200-2000 μm aggregates significantly. With the geometric mean （GMea） of the five test enzyme activities as the integrative index of soil enzyme activities, it was found that under fertilization, the GMea was significantly higher in 200-2000 μm aggregates, suggesting the high sensitivity of enzyme activities in larger particle-size aggregates to fertilization practices. Long-term inorganic plus organic fertilization could enhance the soil bio-function via the promotion of the formation of larger particle-size aggregates and the enzyme activities in these aggregates.

关 键 词：水稻土 团聚体 酶活性 长期施肥 

分 类 号：S154.2[农业科学—土壤学]