Analysis of bioavailability and influencing factors of heavy metals in soil is a key to assess the risk management of heavy metal in soil. This study determines the available Hg, Pb, Cd, Cr, As, Cu and Zn in the soils over Xiaoqinling gold mining region, China, using field survey, on-site sampling, testing and comprehensive analysis. It investigates the relationship between available con-tent of the 7 kinds of heavy metals and correlations between available content and total content, and between available content and the basic physical and chemical parameters of the soils such as particle size, soil pH, and organic matter content. The pollution sources of the heavy metals were analyzed by the correlation analysis and the factor analysis. The results show that the average concentrations of the available heavy metals obtained (mg/kg) were Hg 2.289, Pb 2.289, Cd 2.524, Cr 6.304, As 2.159, Cu 6.304, and Zn 2.159. The variation coefficients of available heavy metals were as follows:Hg>Pb>Cu>zinc>As>Cr>Cd. The gold mine development ac-tivities, the slag and tailings were the main reason for Hg large variability in the soil of the study area. There was a significant correla-tion between available Hg, Pb, Cd, Cu, Zn and total amount;there is a significant correlation between soil organic matter and avail- able heavy metal;there is a significant negative correlation between soil pH and available heavy metal;available heavy metal accumula-tion was not affected by soil particle size.%土壤中重金属生物有效性与影响因素分析是土壤重金属风险管控的关键问题。通过实地调查、现场采样、实验测试、综合分析等方法，分析了研究区100km2内Hg、Pb、Cd、Cr、As、Cu、Zn七种重金属元素的有效态含量特征，研究了这些重金属有效态含量之间、有效态含量与全量、有效态与土壤pH、有机质含量、粒度等基本理化参数之间的相关性，分析了重金属污染来源。结果表明，土壤中Hg、Pb、Cd、Cr、As、Cu、Zn七种重金属有效态的平均含量分别为2.29mg/kg、594mg/kg、2.52mg/kg、6.30mg/kg、2.16mg/kg、48.14mg/kg、50.21mg/kg，其变异系数大小为：Hg＞Pb＞Cu＞Zn＞Cd＞As＞Cr。Hg的变异系数最大，是由于金矿选矿活动采用混汞法提金排放的尾矿堆（库）分布不均。Hg、Pb、Cd、Cu、Zn有效态量与全量之间均存在显著的相关性；土壤有机质与重金属有效态之间存在显著的相关性；土壤pH与有效态重金属之间存在显著的负相关性；土壤粒度对重金属有效态的累积影响不明显。
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