攀枝花市农田土壤钒钛污染特征及风险评价

Risk Assessment and Characteristics of Vanadium and Titanium Pollution in Farmland of Panzhihua City

为探究攀枝花市矿区农田土壤中重金属Ti和V的污染特征并评价其环境风险,在攀枝花仁和区的大花地村、半海村、陶家渡、灰嘎村的农田采集了24个表层土样(0~20 cm),测定土壤样品中Ti和V的总量和有效态含量,再采用单因子污染指数法、地累积指数法、潜在生态危害指数等方法分析了研究区农田重金属Ti和V的污染状况及其环境风险。结果表明:研究区域农田土壤中Ti、V元素的平均值含量均低于四川省土壤背景值,部分采样点位V的浓度高于四川省背景值;重金属Ti和V的有效态含量平均值分别为2.59和4.76 mg/kg,生物有效性系数分别为1.01%和5.66%,相对较低。评价结果表明研究区域内农田土壤中Ti含量未达污染级别,V含量为轻微污染级别,受到污染的矿区需引起相关部门重视,及时采取一定的管控和污染防治措施。

This study aimed to explore the characteristics of vanadium(V)and titanium(Ti)pollution of farmland in Panzhihua mineral region of Sichuan,and evaluate their environmental risks.A total of 24 topsoil samples(depth 0-20 cm)were collected from Dahuadi,Banhai,Taojiadu and Huiga villages in Renhe District of Panzhihua.The total contents of Ti and V metals extracted by the three-acid digestion method,and the contents of soil available Ti and V extracted with 0.1 mol/L calcium chloride were simultaneously determined by ICP-MS.The single-factor pollution index method,geo-accumulation index method,and potential ecological hazard index were used to analyze the pollution status and environmental risks of Ti and V in farmland in the study area.The results show that the average contents of V and Ti in the farmland around the mining area were both lower than the soil background value in Sichuan Province,and the concentration of metal V in some sampling points was higher than the background value in Sichuan Province.The average values of available Ti and V contents were 2.59 and 4.76 mg/kg,respectively,and the bioavailability coefficients were 1.01%and 5.66%,respectively,which were relatively low.The evaluation results demonstrated that Ti content of farmland soil in the study area was not up to the pollution level,while V content was in the range of slight pollution.Relative departments should pay attention to the polluted mineral area,and certain control measures should be taken in time.