| With the rapid development of the society and economy, it is being serious more and more that the harm to eco-entironment which is caused by trash produced by human being activities. The investigation result by regional geochemistrical investigation shows that there is pollution of different extents farming soil in our country and especially the situation is more serious around towns. Thus that causes to human being pay attention to the problem. Because heavy metal elements in the environment will not degradation spontaneously by natural process, it profected by a number of experiment investigation results that the present effect by accumulating of heavy metal elements in the soil to agricultural. However, the effect of long-time or persistent is seldom investigated and further investigation is needed. The author studies systemically characteristics of the activation and transfer heavy metal in soil under acid rain condition. The example of some Hg anomaly in Zhujiang Delta it is showed that experiment investigation on early warning of heavy metal pollution in soil using, and meanwhile, general extractant for analying active component is tesed by ourselves to satisfied the requirements of appraising ecological effect and early warning of pollution heavy mental in soil.In order to complete the investigation, impersonality feasible experiment solutions and devices are designed independently to systemically investigate on activation and transfer characteristic of soil heavy metal under acid rain effect. Primary results are shown as followings:1. PH measuring results of soil solution and eluviation solution show that the ability of experimental plot the acid buffer capacity of soil is stronger under the experiment condition,there is no obvious acidification in soil which after acid rain eluviation.The result has substantial differences with that gotten by most of investigationers in similar work before. The reason probably lies in the difference between the experiment condition of this time and that of before, the most important of which is that weight of soil sample in this experiment is notably greater than that of ancient experiments, and soil used is undisturbed soil which structure and composition are not destroyed. Therefore the proportional relation between joined acid rain and soil which endure acid precipitation is more similar to the acid precipitation course in the nature. Experiment results based on this should be more impersonal and reliable. 2,The effect caused by acid rain on activation and transfer of base ions is undoubted. But during the course of activation and transfer of base ions, expected activation of heavy metals do not appear, which demonstrates that heavy metal elements are not as sensitive to acid rain as what is analyzed in theory.During the course of acid rain eluviation, Zn shows the most activation. Although Zn does not seem to be obviously anomaly, it has the highest concentration in soil solution and eluviation solution, the most activation heavy metal element in acid rain effect. Other elements including Hg, As, Cd, Cu, Pb etc. has weak activation and transfer under acid rain effect and redeposition will take place during the course of their moving from surface soil to deep soil. Contrasted quality standard analysis of surface water, ground water and drinking water, these elements will not bring about negative effect to the water environment and ecological environment of soil. Geochemical investigation results in experimental plot validate reliability of the conclusion.One aspect of activation of heavy metal elements during the course of acid rain eluviation is probably determined by the ability of the acid buffer capacity of soil and the other more important aspect is probably related with their existing forms in the soil. A great deal of investigation results have made it clear that the abnormity of Hg in soil of alluvial plain mainly has something to do with Org.C. This experiment finds cinnabar in soil heavy minerals. Above existing forms of Hg...
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