上海市草莓主产区土壤重金属含量的环境质量分析与评价

Environmental quality analysis and evaluation of heavy metal content in soil of strawberry main production area in Shanghai

为了解上海市草莓产地土壤环境质量状况,以上海市草莓主要产区崇明、奉贤、浦东、青浦、金山5个区县的草莓基地为调查对象,采样分析了草莓基地的土壤重金属镉、铅、砷、汞、铬、铜、锌含量,并评价了土壤环境质量状况。结果表明:被监测区域内土壤各项重金属的含量平均值分别为镉0.101 mg/kg、铅16.111 mg/kg、砷7.972 mg/kg、汞0.123 mg/kg、铬85.860 mg/kg、铜23.248 mg/kg、锌115.329 mg/kg,均低于GB 15618—1995《土壤环境质量标准》和HJ 332—2006《食用农产品产地环境质量评价标准》规定的限量值。土壤中各项重金属的单项污染指数均<1,综合污染指数为0.390,土壤未受到污染,属于清洁水平,适宜发展草莓生产。但大部分监测点重金属铬、汞和锌的含量均高于上海市农业土壤环境自然背景值,其中以锌的平均含量最高,是上海地区土壤环境背景值的1.34倍,说明上海市草莓主产区土壤中重金属铬、汞和锌已经产生了累积,其中锌的累积尤为明显,需及时采取有效措施加强污染监测与控制。

In order to comprehend the soil environmental quality of strawberry base in Shanghai, the contents of heavy metals including cadmium, lead, arsenic, mercury, chromium, copper and zinc in the soil of strawberry base were sampled and analyzed, and the quality of soil environment was evaluated, taking strawberry bases in the strawberry main production areas of Chongming, Fengxian, Pudong, Qingpu, Jinshan as the research objects. The results showed that the average contents of Cd, Pb, As, Hg, Cr, Cu and Zn in the soil of five districts is 0. 101 mg/kg, 16. 111 mg/kg,7. 972 mg/kg,0. 123 mg/kg,85. 860 mg/kg,23. 248 mg/kg, 115. 329 mg/kg, respectively,which were all below the limit value in GB 15618--1995 ＂environmental quality standard for soils＂ and HJ 332-2006 ＂farmland environmental quality evaluation standards for edible agricultural products＂. The single contamination index of soil heavy metal was below 1 and the comprehensive contamination index was 0. 390. The soil was not contaminated and at the clean level, indicating that the soil was suitable for strawberry production. But the heavy metal content in most monitored areas was higher than Shanghai soil environmental background value. The average content of zinc was the highest,which was 1.34 times of the background value of soil environment in Shanghai. These results demonstrated that heavy metals Cr, Hg and Zn had been accumulated in in the soil of these monitored areas, especially the accumulation of zinc. The government needs to take effective measures to strengthen the pollution monitoring and control.