Environmental Effects Of Heavy Metal Elements In Soil-rice Plant System In Hefei Suburb

With the acceleration of the urbanization construction, the industrial production and human dailylife have brought much "three wastes". The surrounding soil environment is polluted, and the human being's health in the area is affected. While The crop is much planted in Hefei, crop circle directly involved in the food chain cycle. So, it's becoming more insidious if the heavy metals enter inteo the human body through the food chain.This paper is based on many subjecets, such as pedology, ecology, environmental geochemistry and so on. Through careful field work and laboratory analysis, we give a systematic analysis in the paper on the current conditions of heavy metal pollution in the rhizosphere soil and the rice, do research the content and spatial distribution of the heavy metal in crops.The research on the heavy metal content of soil shows that the heavy metals in two palces have varying degrees of accumulation, Cd is the most, the other's turns is followed :Hg> Zn> Pb> Cu> As> Cr> Ni, but only Cd in Daxin area and Hg in Yicheng area exceed the National Second Standards. The regional pollution of heavy metals is obvious, the accumulation of Cd mainly occurred in Daxing district, and the accumulation of Hg mainly in Yicheng.Through the research of heavy metals in the rice plant, the laws of accumulation of heavy metals in different organs of rice plant are:The regulation of accumulation and distribution of Cu is root>leaf>stem>seed;The regulation of accumulation and distribution of Cd in Daxin area is root> stem>seed>leaf, while in Yicheng area the regulation of accumulation and distribution of Cd is root> stem>leaf >seed;The regulation of accumulation and distribution of Cr is root>leaf>stem>seed;The regulation of accumulation and distribution of Ni is root>leaf≈stem≈seed;The regulation of accumulation and distribution of Pb is root>stem≈leaf>seed;The regulation of accumulation and distribution of Zn in Daxin area is root> stem>seed>leaf, while in Yicheng area the regulation of accumulation and distribution is root>seed >stem>leaf;The regulation of accumulation and distribution of Hg in Daxin area is root> stem>leaf>seed, while in Yicheng area the regulation of accumulation and distribution is root>seed > stem>leaf;The regulation of accumulation and distribution of As is root> stem>leaf >seed.Through careful analysis on the correlation of contents of each heavy metals in rice plant and the correlation of heavy metals in the soil and plant, we can infer that most correlations of heavy metals are not very obvious, which showed that the contents of heavy metals in rice plant is not only affected by the corresponding elements in the soil, also affected by many facors such as the pH, the physical and chemical properties of soil, the effectiveness of elements in soil, and the accumulations of elements in different parts of rice.