大港河小流域土地利用方式对土壤肥力影响的研究

Effects of Land Use Types on Soil Fertility in Dagang Watershed

采用野外调查、取样和实验分析相结合的方法对江苏省宜兴市大港河小流域内4种主要土地利用方式(林地、水田、茶园、灌丛)的土壤理化性质进行对比研究,讨论不同土地利用方式对土壤肥力的影响,结果表明:不同土地利用方式对土壤肥力的影响不同,土壤有机质和全氮质量分数变化依次为灌丛>林地>茶园>水田;农业耕作活动对表层土壤物理性质影响较显著,0～20 cm层的土壤含水率变化顺序为水田>灌丛>林地>茶园;20～40 cm层的土壤含水率呈现出不同的变化规律,其顺序为灌丛>林地>水田>茶园;0～20 cm层的土壤容重变化顺序为水田>灌丛>茶园>林地;20～40 cm层的土壤容重呈现同样的变化规律。

Soil physical and chemical properties under the four main types of land use（forest land,paddy field,tea garden and bush land） in Dagang watershed,Yixing,Jiangsu Province,were studied through field soil sampling and laboratory analysis.The effects of different land use types on soil fertility have been discussed in this paper.The results show that different land uses have different effects on soil fertility.Both soil organic matter and total nitrogen content decline in a sequence from bush land,forest land and tea garden to paddy field.Simultaneously,farming practice has significant impacts on the physical and chemical properties of surface soil.The soil water content of the 0~20 cm layer is in the order of paddy field bush land forest land tea garden.Compared with the 0~20 cm layer,the 20~40 cm layer shows a different variation in the order of bush land forest land paddy field tea garden.The soil bulk density of the 0~20 cm layer and the 20~40 cm layer have the same change in the order of paddy fieldbush landtea garden forest land.