对张家港地区水稻籽粒中重金属元素Cu、Pb和Cd的含量及其空间变异性进行了研宄。结果表明:与《国家食品卫生标准》(GB2762.2005)相比,张家港局部地区的水稻样品存在着Pb超标现象,超标样点主要出现在某些企业周围;Cu、Cd不存在超标情况,但在某些工厂企业周围含量较高,应当引起注意;空间分布上,水稻重金属Cu、Pb含量在雏形土地区明显高于人为土地区,而水稻中Cd的空间分布则相反;工业活动导致的土壤重金属含量异常对水稻中元素含量影响也较突出,不同类型的工厂企业对水稻重金属的影响不同,化工类企业周围的水稻重金属Cu和Cd含量要明显高,水稻重金属Pb在冶金类企业周围的含量要明显高;土壤重金属Cu、Cd全量对水稻Cu、Cd含量和富集有着明显的影响,土壤pH的变化对水稻中Cd元素的富集有明显的影响。这些结果为该市农产品质量安全的评价和针对性农业管理措施的开展提供了重要的基础资料和参考依据。
Zhangjiagang county in Yangtze River Delta region was chosen as the typical area to study the spatial variation of heavy metals of copper (Cu), lead (Pb) and cadmium (Cd) in rice grains. Results indicated that Pb content in rice grains of some samples was significantly higher than the National Food Health Standard (NFHS) (GB2762-2005). Most of those samples appeared in the areas near the industries. Cu and Cd in rice grains had no threat to human's health at present, but attentions should be taken to the accumulation of Cu and Cd in the areas near the industries. Spatially, Cu and Pb contents in rice grains were higher in Anthrosols than in Cambosols but converse to Cd (p〈0.05). Heavy metal contents in rice grains also depended on the types of industries. Cu and Cd were higher in the areas close to the chemical industries, while Pb was higher in the areas close to the metallurgy industries. The accumulations of Cu and Cd in rice grains were significantly affeeted by their contents in soil, and accumulation of Cd influenced by soil pH as well. These results can provide important basic information and reference for assessing security of agricultural product quality and performing effective agricultural management in the region.