怀化市郊农业土壤重金属含量及其污染评价

为了解怀化市郊农业土壤重金属含量特征以及为怀化市发展绿色食品生产提供科学依据，利用INNOV-X土壤重金属分析仪测定了怀化市郊不同乡镇、不同土地利用类型土壤中Cr、Cu、Zn、As和Pb的含量，并采用单因子污染指数法和综合污染指数法进行了土壤重金属污染的评价。结果表明：怀化市郊各乡镇、各土地利用类型土壤中Cr、Cu、Zn、As和Pb含量基本上均低于国家二级标准和绿色食品产地环境质量标准，单项污染指数（除个别采样点外）以及综合污染指数均小于1，即不存在重金属元素的污染，适合绿色食品基地的建设。但有些乡镇和地类的综合污染指数较高，污染等级达到了警戒级，如杨村乡和盈口乡的综合污染指数分别为0.87和0.71，苗圃和果园的综合污染指数分别为0.96和0.73，尤其是苗圃，即将接近轻度污染。因此，采取预防并控制怀化市郊农业土壤重金属污染的相关措施对于怀化市发展绿色食品生产意义重大。

Heavy Metal Concentrations and Pollution Assessment of Agriculture Soil in Huaihua Suburbs

In order to understand the content of heavy metal in agriculture soil of Huaihua suburbs and provide scientific basis for developing green food production, this research studied the content of Cr, Cu, Zn, As and Pb in different towns and land use types of agriculture soil by using INNOV-X soil heavy metal measurement instrument. It also made the assessment of heavy metal pollution by the method of single factor pollution index and the synthesis pollution index. Results showed that, the content of Cr, Cu, Zn, As and Pb in different towns and land use types of agriculture soil was almost lower than national secondary standard and green food producing area environment quality standard. Both the individual pollution index and the synthesis pollution index were less than 1, which mean there was no heavy metal pollution and the soil was suitable for green food base construction. But the synthesis pollution index of some towns and land use types reached to the alert level. The synthesis pollution index of Yangcun village and Yingkou village were 0.87 and 0.71, and the synthesis pollution index of orchard and nursery were 0.96 and 0.73, especially the nursery almost reached to the light pollution level. Therefore, take measures to prevent and control the heavy metal pollution of agriculture soil is very important to develop the production of green food of Huaihua City.