徐州柳新地区耕地土壤Se-Hg-Cd-Pb元素地球化学特征与生态风险评估  

Geochemical characteristics of Se-Hg-Cd-Pb elements and ecological risk assessment at farmland in Liuxin district of Xuzhou City

作　　者：丁晨龙 何金先[1] 程晓雪 黄成 吴泓辰 DING Chenlong;HE Jinxian;CHENG Xiaoxue;HUANG Cheng;WU Hongchen(School of Resources and Geoscience,China University of Mining and Technology,Xuzhou 221116,Jiangsu,China;State Key Laboratory of Environmental Geochemistry,Institute of Geochemistry,Chinese Academy of Science,Guiyang 550002,Guizhou,China)

机构地区：[1]中国矿业大学资源与地球科学学院,江苏徐州221116 [2]中国科学院地球化学研究所环境地球化学国家重点实验室,贵州贵阳550002

出　　处：《矿产与地质》2022年第5期1056-1066,共11页Mineral Resources and Geology

基　　金：国家级大学生创新训练项目(202010290034Z);中国矿业大学校级大学生创新训练项目(2020199cx);国家自然科学基金项目(No.41702170)共同资助。

摘　　要：为探究徐州市柳新地区采煤塌陷回填复垦耕地土壤Se元素含量和潜在的生态风险,针对该地区表层土壤中Se、Cd、Hg、Pb四种元素的分布特征,采用多元统计分析、GIS空间插值技术、内梅罗指数、地累积指数和潜在生态风险评估法进行元素分布特征探究和生态风险评估。研究结果表明:研究区表层土壤Se元素平均质量分数为0.36×10^(-6),高于全国土壤背景值,且远高于江苏省平均值;土壤Se元素变异系数为50.87%,处于强变异水平,Se浓度和不均匀性可能是受到了人类活动(如塌陷回填物、采煤、燃煤等)的影响。研究区内Hg、Cd、Pb元素的平均质量分数分别为0.043×10^(-6),0.15×10^(-6),21.4×10^(-6),均小于江苏省土壤平均值,其中Hg、Pb平均值小于全国土壤背景值,而Cd含量则高于全国土壤背景值。Hg和Cd元素在研究区土壤中分布不均匀,推测受到局部发电、冶金等点污染源影响较大,而Pb元素分布则较为均匀,局部高异常推测与发电企业有关。研究区无明显的Hg、Pb污染,部分地区存在Cd元素的轻度污染。徐州柳新地区采煤塌陷复垦耕地初步评估为富Se低污染耕地,具有良好的商品粮耕作价值。In order to explore the selenium content and potential ecological risk of reclaimed farmland soil in Liuxin district of Xuzhou City, the distribution characteristics of four elements(Se, Cd, Hg, Pb)in the surface soil of this district are studied. Multivariate statistical analysis, GIS spatial interpolation technology, Nemerow pollution index, geo-accumulation index and potential ecological risk assessment method were used to explore the distribution characteristics of elements and evaluate the ecological risk. The results showed that the average content of selenium in the surface soil of the study area is 0.36×10^(-6), which is higher than the national soil background value, and is much higher than the average value of Jiangsu Province. The variation coefficient of Se in soil is 50.87%, which is at a strong variation level. The concentration and inhomogeneity of Se may be affected by artificial factors, such as subsidence backfill and coal mining. The average contents of Hg, Cd and Pb in the study area are 0.043×10^(-6), 0.15×10^(-6)and 21.4×10^(-6)respectively, which are lower than the average value of soil in Jiangsu Province. The average contents of Hg and Pb are lower than the national soil background value, while the Cd content is higher than the national soil background value. Hg and Cd elements are unevenly distributed in the soil of the study area, and it is speculated that local power generation, metallurgy and other dotlike pollution sources have a greater impact, while the distribution of Pb is relatively uniform, the local high anomaly is speculated to be related to power generation enterprises. There is no obvious Hg and Pb pollution in the soil of study area, while some areas have a slight pollution of Cd. The reclaimed farmland of coal mining subsidence in Liuxin district is preliminarily evaluated as selenium-rich and low-pollution cultivated land.

关 键 词：土壤硒 重金属 空间分布 生态风险评估 采煤复垦地 柳新地区 

分 类 号：P595[天文地球—地球化学]