不同土壤类型下Cd和Pb在水稻籽粒中累积特征及其环境安全临界值  

Accumulation characteristics of Cd and Pb in rice grain and their security threshold values in paddy field under different soil types

作　　者：范中亮[1] 季辉[1] 杨菲[1] 吴琦[1] 张卫建[1,2] 

机构地区：[1]南京农业大学应用生态研究所,江苏南京210095 [2]中国农业科学院作物科学研究所//农业部作物生理生态与栽培重点开放实验室,北京100081

出　　处：《生态环境学报》2010年第4期792-797,共6页Ecology and Environmental Sciences

基　　金：国家"十一五"科技支撑计划课题(2006BAD02A15;2007BAD89B12);公益性行业(农业)科研专项(200803028)

摘　　要：研究水稻籽粒对土壤重金属的累积特征和水稻产地土壤重金属安全临界值,可为水稻安全生产和产地安全适宜性评价提供重要参考。以杂交籼稻KU818作为材料,通过外源添加不同质量分数的Cd和Pb,于2008年在南京采用盆栽试验方法,研究不同土壤类型下水稻籽粒对土壤重金属Cd和Pb的累积特征及其环境安全临界值。结果显示,水稻籽粒对重金属的累积量总体上随着外加重金属质量分数的增加而呈现增多趋势,籽粒中重金属含量与处理水平及盆栽土壤中重金属有效态含量呈现显著或极显著正相关。籽粒对Cd、Pb的累积特征呈现出土壤类型之间的显著差异,水稻土栽培下,籽粒对重金属的累积高于潮土栽培下的。根据国家《食品中污染物限量(GB 2762-2005)》标准中重金属的限量标准和水稻籽粒重金属的累积特征推算出水稻产地(潮土和水稻土)安全临界值:Cd为1.63 mg.kg-1和0.74 mg.kg-1,Pb为230 mg.kg-1和110 mg.kg-1,均高于国家《食用农产品产地环境质量评价标准(HJ 332-2006)》的指标。结果表明,由于临界值在土壤类型之间差异较大,制定统一的农产品产地重金属限量标准还需结合当地土壤性质加以评价。Increasing publics attentions have been paid to the concerns of toxic heavy metals contamination of human food.Rice is the most important staple food in China,and the highway construction has developed quickly during the last decades,implying a contamination high risk of rice sown around the roadsides.To learn the accumulation characteristics of toxic heavy metals in rice grain growing around the highway and their safety threshold will contribute a great to rice cropping with high safety and environmental security assessment of paddy field.Therefore,we conducted pot cultivation experiments with two exogenous heavy metals of Cd and Pb and one hybrid Indica rice（KU 818） under two typical soil types（Alluvial soil and Paddy soi） in Nanjing,Jiangsu province,in 2008.Our objectives were to investigate the accumulation characteristics of soil Cd and Pb in rice grain and their environmental security threshold.Results showed that the contents of Cd and Pb in rice grain increased along with the treatments level,and that the contents were significantly positively correlated with the treatments level and the effective contents of Cd and Pb in soils（P0.05）.The accumulation characteristics of Cd and Pb in rice grain indicated significant differences between the two soil types.The contents of Cd and Pb in rice grain were significantly higher in the paddy soil than in the alluvial soil.According to the National Standards of ＂Codex General Standard For Contaminants And Toxins In Foods（GB2762-2005）＂ and the accumulation characteris-tics of Cd and Pb in rice grain,we calculated the security threshold values of Cd（1.63 mg·kg^-1） and Pb（230 mg·kg^-1） for Alluvial soil,and Cd（0.74 mg·kg^-1） and Pb（110 mg·kg^-1） for Paddy soil.These threshold values are higher than the National Standards of ＂Farm-land environmental quality evaluation standards for edible agricultural products（HJ332-2006）＂.Since the threshold varies widely between soil types,this study suggests that local soil properties sh

关 键 词：Cd PB 植物富集 土壤类型 安全临界值 

分 类 号：S152[农业科学—土壤学]