| Green food and organic food production has been more and more important for people since economic development and live level increase. China is one of the important original region for citrus production where the plant area is the first and productive output is the third in the world. In the Three-Gorge Reservoir Region of Chongqing citrus production has been pillar industry for agriculture. Accompany with the life level increase, environmental condition and ecological system will be pay more attention to citrus production. Non-polluted agricultural production is the most important approach for high quality and high efficiency, while soil environmental quality standards of heavy metal is imperative for environment monitoring and assessment.In the soil-plant system litter of heavy metal is enriched by plant, most of them will exist in the soil a long time. It is necessary to understand the form and distribution of heavy metal pollution, as well as the characteristics and the law of varied plant absorbing the heavy metal. Soin this paper the research has been done about the heavy metal ecological behaviors of soil-citrus system of the Three-gorge Reservoir Region in Chongqing.Heavy metal ( Hg, As, Cd, Pb and others) have a great effect to human being health through food links. Heavy metal also effect crop output and quality in the soil-plant system, the factors were analyzed which influence the transport and transformation of heavy metal. Combined pollution caused by organic pollutant and heavy metal and interaction of heavy metal is one of the important environmental pollution forms. Phytoextraction and remedy of polluted soils by heavy metal was also discussed.Among heavy metal elements of polluted soil, cadmium (Cd) toxicity is famous. Some aspects related to the mechanisms of Cd toxicity the plants, e.g., plant growth, photosysthesis, stomatal action, water relations, efflux of cation and enzyme activity were effected by Cd. It was demonstrated that bioavailability of Cd is related with pH, microorganisms, and other elements in rhizosphere of soils. The way of mercury (Hg) pollution, transportation and harness method in soil were discussed witch including atmospheric deposition, emissions of Hg from soil, effect of Hg on plant growth and development. Copper (Cu) is one of necessary elements, but Cu is also a high toxicity and wide-spread heavy metal pollutant, excessive Cu can decrease the membrane integrity, the activity of enzymes, change the synthesis of chlorophyll and the efficiency of the primary photochemical reactions. Zinc (Zn) and nitrogen interaction has the influence to plant growth and the uptake of P, K, Fe and other elements. The effects of Nickel (Ni), Lead (Pb), Arsenic (As) and Chromium (Cr) to plant and soil are also discussed. Heavy metal impact on the cytoplasmic function in a number of different ways, principally by their binding to protein sulfhydryl groups, by producing a deficiency of ions, by substituting the essential ions. Other modes of toxicity are including disruption of cell transport processes and oxidative damage by free radicals.This paper analyze the heavy metal content of citrus different organs, citrus different strains and ecological environment of the Three-gorge Reservoir Region in Chongqing. The heavy metal ecological behave in soil-citrus ecological system was research by studying in soil-citrus ecological system. The area of citrus research is Feng Jie county, Zhong county, Chang Shou county and Jiang Jin county in Chongqing.The object is to obtain a scientific evaluate for environmental quality of citrus orchards and citrus fruit security of the Three-gorge Reservoir Region in Chongqing by the current effective standards of China. The discuss is also done to understand the way of soil heavy metal pollution incitrus orchards and citrus fruit, the biological influence of heavy metal to soil-citrus ecological system to build a ecological model of security high quality citrus production in the Three-gorge Reservoir Region.1. Investigation a...
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