Studies On The Heavy Metal Pollution Risk Evaluation In Dong-Ting Lake And Remediation Technology In Situ

Soil heavy metals content and Heavy metals in soil and crop production, food security and the environment and human health are closely related, and it is the most basical most important research in soil quality changes. The paper is base on vegetable plant soil in Dong-Ting Lake in Hunau province,Brassica rapa original place Cadmium pollution soil rehabilitation and regulate experiment,Brassica rapa screening experiment In a basin,in order to provide reason for vegetable plant and pollution soil utilization.Chapter I of the thesis mainly introduces the research's purpose, meaning and methods etc.Chapterâ…¡A survey was conducted in the 19 vegetable cropping region of Yueyang, Huarong, Nangxian, Yuanjing, Yiyang and Xiangyin, Dongting Lake Plain to study pollution status of heavy metal in vegetable soils. The contents of heavy metals of Cd, Pb, Cu and Zn in top soil were mesured and single pollution index and comprehensive pollution index were applied in the survey. Th results showed that:the orders of heavey metabl pollution was Cd> Zn> Cu in vegetable soils. Pollution of Pb was not measured in the whole study area. Based on the pollution index and comprehensive pollution index of soil heavy metals, the Yuanjing, Yiyang and Xiangyin soils belonged to pollution soil, needing to be remediated. By contrast, the soils collected from Yueyang, Huarong and Nangxian belonged to the clean soil, suitable for the cultivation of green vegetables.Chapter III In a field experiment of Chinese white cabbage, the improvement of Cd contaminated soil by different soil amelioration materials was conducted during double successive growing seasons from Oct.2010 to Dec.2010 in Qing Shui Tang region, Zhuzhou, to reducing the Cd content of agricultural products in Cd contaminated soil. Fresh weight of Brassica rapa aboveground was no difference among three ameliorion treatments. Compared to CK treatment, the soil pH was suitable for growing for Brassica rapa in calcium magnesium phosphate treatment. The content of Cd of Brassica rapa aboveground and DTPA-extraced Cd in soil decreased while fresh weight of Brassica rapa aboveground increased significantly with calcium magnesium phosphate treatment.Chapter IV The low Cd uptake and accmulation cultivars in the Cd pollution soil, was studied in this study. Twenty seven cultivars of Brassica was conducted with the Cd pollution soil in the pot study in the greenhouse. The results showed that the percentage of Cd content of edible part exceeded the National Edible standard was 85.2% on the 2.31mg/kg Cd soil. The Cd content of shoot of cultivar Jin chuan number 9, Qiu tian huo zhi qing, Ai jiao huang and Chun run jia mei was lower than the concentraction of National Edible standard, which could be cropped in the light Cd pollution soil.Chapter V is base on the experiment data,draw to the master conclution.