生长于铬污染土壤上石榴产品铬污染评价

研究了攀西地区铬污染土壤和正常土壤铬含量分布及其石榴样品铬污染情况。结果表明攀枝花大田石榴基地土壤铬含量在23．1—504mg／kg，平均值高达184mg／kg，超标率为26％，而对该基地的石榴果实进行两年连续监测结果表明，铬含量在0．0012—0．067mg／kg之间，平均为0．016mg／kg，大大低于相应产品标准（0．5mg／kg），超标率为0％；会理石榴基地土壤铬含量在34．5—99．1mg／kg，平均值为69．0mg／kg，超标率为0％，该基地的石榴果实铬含量在0．0075—0．104mg／kg之间，平均为0．024mg／kg，大大低于相应产品标准（0．5mg／kg），超标率为0％。形态分析表明土壤中铬99％以上都是以不被植物利用的残渣态存在，因此土壤总铬再高，其被植物可吸收部分却很少，这就导致了受铬污染的土壤却不一定能生产出污染石榴的原因。

Assessment of Cr Pollution of the Megranate Products Growing in the Soil Polluted by Cr

Cr content in normal soil and that polluted by Cr as well as in megranate growing on the test soils were analyzed in Panxi District. The results showed that for the Datian Megranate Planting Base in Panzhihua City, the Cr content changed from 23. 1 to 504 mg/kg in soil with a high average up to 184 mg/kg and 26% over the standard. While the Cr content in the megranate,according to the test lasting for two years, was from 0. 0012 to 0. 067 mg/kg with an average of 0. 016 mg/kg which was much lower than the standard （0. 5mg/kg） and none over the standard. In soils of Megranate Planting Base of Huili, the Cr content was from 34. 5 to 99. 1 mg/kg with an average of 69. 0 mg/kg and none over the standard. The Cr content in megranate was between 0. 0075 and 0. 104 mg/kg with an average of 0. 024 mg/kg, which was much lower than the corresponding production standard （0. 5mg/kg） and none over the standard. According to the morphological analysis, more than 99% of Cr in soil exists as residues which could not be absorbed by plants. Therefore, in spite of high total Cr content in soil, little Cr could be absorbed by plants. That is why the Cr polluted soil may produce megranate without Cr pollution.