江西赣州梓山地区富硒土壤重金属元素安全性评价

Safety evaluation of heavy metal contents in selenium-rich soil in the Zishan area,Ganzhou,Jiangxi Province

在江西梓山地区采集土壤样712件、水稻样46件,分析该区土壤、水稻中As、Cd等重金属元素含量及其在土壤—水稻系统中的安全性。研究区土壤环境质量总体优良,清洁和较清洁土壤图斑面积为11 883.06hm2,占全区面积的96.82%;轻微污染的土壤图斑面积为368.66hm2,占全区面积的3.00%;重金属污染的土壤图斑主要分布于富硒土壤区。水稻中As等重金属元素含量较低,均符合国家食品安全标准。水稻对As等元素的吸收富集能力受其土壤总量及其有效性制约,而重金属元素的生物有效性主要受重金属总量与TFe2O3的控制。研究区土壤脱硅富铁铝的特征表明,该区土壤As等重金属元素的生物有效性较低,可开发富硒水稻。

712 soil samples and 46 rice samples were collected in the Zishan area of Jiangxi Province to test the contents of heavy metals （such as As, Cd, etc） in the soil and rice and finally evaluate safety of land environment in the Zishan area. The test results show that soil environment quality of the study area is generally good. The clean soil area covers an area of 11 883.06 hm2 ,which takes up 96.82% of the total area. The slightly polluted soil area has an area of 368.66 hm2 ,which takes up 3.00% of the total area. The soil polluted by heavy metals is mainly distributed in Se-rich soil areas. The contents of heavy metals such as arsenic in rice samples are low and meet the national food safety standards. Absorption and enrich- ment ability of rice to heavy metal elements such as As is controlled by soil amount and validity. While bio-availability of heavy metals is mainly controlled by the total heave metal amount and TFe2 03. Soil charac-teristic of desiliconization and ferrallitic enrichment indicates that the biological effectiveness of heavy metals such as As is low in the area, which can be used to grow Se-rich rice.