不同植茶年限土壤微团聚体及有机碳分布特征  

DISTRIBUTION CHARACTERISTICS OF SOIL MICRO-AGGREGATES AND ITS ORGANIC CARBON IN DIFFERENT TEA PLANTATION AGE

作　　者：吴铭[1] 郑子成[1] 李廷轩[1] 罗键[1] 樊西凌 代莉[1] 

机构地区：[1]四川农业大学资源环境学院,四川成都611130

出　　处：《长江流域资源与环境》2014年第7期999-1005,共7页Resources and Environment in the Yangtze Basin

基　　金：国家自然科学基金项目(40901138);四川省学术和技术带头人培养基金项目(2012);四川农业大学大学生创新性实验计划项目(121062660);四川省大学生创新创业训练计划项目(201310626032)

摘　　要：采用野外调查和室内分析相结合的方法,就不同植茶年限土壤微团聚体及有机碳分布特征进行了研究.结果表明：（1）茶园土壤微团聚体含量随粒级的减小而减小;＞0.05 mm和0.05～0.01 mm粒级微团聚体含量随着土壤深度的加深而增大,而0.01～0.005 mm、0.005～0.001 mm和＜0.001 mm粒级微团聚体含量随着土层深度加深而减少;（2）茶园土壤微团聚体有机碳含量随微团聚体粒级的减小而增加;随植茶年限的延长,各粒级微团聚体中有机碳含量增加;不同植茶年限茶园土壤总有机碳含量随土层深度的增加而减少;（3）微团聚体对土壤有机碳的贡献率以＞0.05 mm粒级为主,0.05～0.01 mm粒级次之,0.005～0.001 mm粒级最少.随着植茶年限的延长,＞0.05 mm粒级微团聚体对土壤有机碳的贡献率呈减小的趋势,0.05～0.01 mm粒级微团聚体对土壤有机碳的贡献率呈增加的趋势,而其它粒级的微团聚体则呈现先增大后减小的变化趋势,并在植茶21～23 a达到最大值.Through field investigation and laboratory analysis, distribution characteristics of soil micro- aggregates and organic carbon under different tea plantation age were studied. The results showed as follows.（1） The tea garden soil micro-aggregate concentrations decrease with the decrease in the particle size in general, indicating that tea garden soil in the study area has stronger ability of protecting fertilizer. In the upper （0- 20 cm） soil layer, along with the extending length of planting tea, concentrations of micro-aggregates in the sizes of〉 0.05 mm, 0.01- 0. 005 mm and 〈 0. 001 mm show a ＂A ＂ type changing pattern, concentrations of the remaining fraction present an increasing trend. In the lower soil layer （20--40 cm）,graded levels of micro-aggregates in the sizes of 〉 0.05 mm and 0.05--0. 01 mm varied obviously with plant tea length extended, while concentrations of the remaining three grades of micro-aggregates remain stable with increases in years planting tea. （2） Tea garden soil organic carbon concentration with micro-aggregate fraction increases with the decrease in the micro-aggregate concentrations.This is because the soil micro-aggregate fraction is smaller, the specific surface area is larger,and the organic carbon adsorption ability is stronger. Along with the increase in planting tea fixed number of year, the organic carbon concentration in the micro-aggregate graded increases. This is mainly due to fact that in the natural soil after planting tea,a lot of old leaves return soil,bringing large amounts of carbon sources.Total organic carbon concentrations of different fixed number of year of the tea garden soil decrease with the increase in soil depth, mainly because of the mobility of the soil organic matter and organic matter source of the differences.（3） Micro-aggregate contribution to〉 0.05 mm of soil organic carbon fraction is given priority to,granule grades of 0.05--0.01 mm,0. 005--0. 001 mm grade at least. With increasing years of planting tea, micro-agg

关 键 词：植茶年限 土壤微团聚体 有机碳 

分 类 号：S152.4[农业科学—土壤学]