The Research On Distribution Characteristics Of Heavy Metals And Agricultural Application In Water And Sediment Of Jinyang Lake

This paper takes Jinyang Lake’s water and sediment as research objects. Water and sediment in different function areas (power plants, resort, fishing zones) are sampled and the heavy metal elements of water and sediment are analyzed. At the same time, this paper studies environment and ecological risk of the five heavy metals (Cu, Cr, Zn, Ni, Pb) in sediment by taking different evaluation methods. Based on the study, this paper designs and implements experiments to study the influence of sediment when it is used as agricultural soils by adding regional sediment to the soil tested. The main conclusions are as follows:(1) Jinyang Lake is influenced by power plant’s cooling circulation water, aquaculture base, human activities and its pollution can’t be ignored. The content of elements in surface water is different among areas. Pb element is higher than other regions which should be paid attention to.(2) The average content of heavy metals in the Jinyang Lake’s sediment is sorted as Cu> Zn> Pb> Cr> Ni, the average Cu, Pb are2.85,2.57times compare with Taiyuan background soil value respectively which may be affected by transportation, power plants, chemical industrial activities and other human activities. On the analysis of sediment, the sediment can meet the Control standards for pollutants in sludges from agricultural use.(3)The Jinyang Lake’s sediment is evaluated by three ways. Judging from the results of the index of integrated and pollution, three regions of the Jinyang Lake’s water are moderate polluted, and the pollution is mainly caused by the Cu, Pb; By evaluating index of Geoaccumulation, the three regions have mild Pb pollution whereas the power plant area and resort have mild Cu contamination; By using the potential ecological risk of the heavy metal index method, it can be seen that the five kinds of heavy metals’ potential ecological risk orders are as follows:Cu> Pb> Ni> Zn> Cr, the Jinyang Lake pollution is in the low-risk status, and its water surface sediments’ potential ecological risk is slight. (4) Chemical speciation of heavy metals of Jinyang Lake’s sediment is researched. The Cu, Ni, Pb, Cr elements of Jinyang Lake’s sediment mainly exist in residual status, they are lower biological activity and are safe for agricultural use. But Zn has potential ecological risk which is highly toxicity and has high biohazard.(5) The thesis takes the research object as the soil of the area of XiaoDian as subsoil by adding sediments in different regions of jinyang lake in taiyuan. The results show that the unstable state of each heavy metal in soil increased by the addition of sediments. However, its potential perniciousness was smaller due to the small proportion.