为揭示白银区东大沟流域耕地土壤Cd的分布特征及其影响因素，对采集土样的Cd、土壤有机质、全氮、全磷、CEC、pH、土壤脲酶、蔗糖酶、过氧化氢酶和多酚氧化酶含量进行了测定，运用GIS手段分析了耕层土壤Cd空间分布特征。结果表明，耕层土壤Cd浓度范围0.170～82.400 mg/kg，属重度污染。土壤Cd含量高值区出现在沙坡岗和民勤村，呈岛状分布，并以此为中心Cd浓度向周边方向递减。Cd土壤剖面分布具有明显的表层富集规律，符合负指数方程递减规律。表层土壤Cd含量与有机质呈显著正相关，与pH呈极显著负相关。

This study is aimed to explore Cd distribution characteristics and its influence factors in cultivated soil from Dongdagou in Baiyin district of Baiyin city， Gansu province. The content of Cd， soil organic matter， total N， total P， CEC， pH， soil urease， invertase， catalase and polyphenol oxidase in soil are measured， and the spatial distribution data of Cd are obtained with ArcGIS method. The result shows that the arable layer soil is polluted seriously， the range of Cd contents is 0.170~82.400 mg/kg. The high value area of Cd contents with island-like spacial distribution located mainly in Shapogang and Minqin village， in which Cd contents decreased around. Cd distribution has obvious enrichment regularity in the surface layer of soil profile， and the significant model of negative exponential function is found for Cd. Cd contents are significantly positively correlated with organic matter， and it are very significantly negatively correlated with pH.

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甘肃省青年科技基金计划“白银矿区土壤镉迁移转化与粮食质量安全的耦合规律研究”(2013GS06935)；甘肃科技计划软科学项目“白银矿区土壤重金属污染现状、趋势及对策研究”(1305ZCRA174)