河北省优势农产品——小麦、玉米主产区土壤重金属分布研究

通过计算每种重金属含量极差,制作每种重金属次数分布图,对河北省优势农产品——小麦、玉米主产区20.53万hm2农田的1 535个土壤样品中8种重金属含量检测数据进行了分布规律研究。结果表明:河北省小麦、玉米主产区不同的土壤重金属含量分布也不同,有的元素接近正态分布,如砷和镍,有的是属于偏态(对数正态)分布,如铅、镉、锌、铜、汞和铬。在剔除异常数据后,对剩余数据再制作次数分布表,可以看出,将数据修正后,铬、锌、铜接近正态分布,铅和汞仍然属于偏态分布。

Contents of Several Heavy Metals in Soils with Predominantly Growing Wheat and Maize in Hebei Province

As many as 1 535 soil samples representing 205.3 thousand hm2.of farmland predominantly growing wheat and maize in Hebei province were analyzed in order to probe contents of 8 heavy metals.Times distribution charts of all data for all elements with 30 groups were drawn.By calculating extreme dispatch of every heavy metal contents to make the time distribution chart of every heavy metals.The result indicated that in the main wheat and maize area,different elements had different content distributions.Some elements showed nearly normal distribution such as As and Ni.The other elements showed logarithmic distribution,including Pb,Hg,Cd,Cr,Cu and Zn.After deletion of abnormal data,the rest data were grouped into 30 subgroups.The result showed that some elements showed nearly normal distribution,such as Cr,Zn and Cu.But the elements of Cd,Hg and Pb were still showed logarithmic distribution.