| With the rapid development of modern industry and urban pollution, and the extensive application of agricultural chemical substances to soil made heavy pollution problems become more serious. Heavy metals accumulated in plant roots, stems, leaves and seeds, which will not only seriously affected plant growth and development, but also entered the food chain and endangered human health. Copper and zinc were essential trace elements for animal and plant growth, meanwhile they also contaminated soil. Soil adsorption-desorption processes controlled the concentration of heavy metal ions, which was one of the main chemical processes. Copper and zinc adsorption-desorption of soil controlled prividing copper and zinc of the soil and cushioning capacity of copper and zinc, which determined the plants absorbed the amount of copper and zinc from the soil, and also determined the largest copper and zinc capacity from the outside which the soil can sustain.The experiment studied the migration of copper and zinc in soybean plants and their adsorption-desorption in the black soil area, it will provide theoretic basis for establishing environment standard and confirming environmental capacity of copper and zinc in the black soil area.The results showed that:1 The contents of copper and zinc in the upper of soybean plants increased as the increased used of copper and zinc, the two were highly positively correlated, the absorption rate of plants (the content in plants/soil input concentration* 100%) decreased as the increased used of copper and zinc. In addition to the contrast, when the same copper and zinc applied to the soil, the content of copper and zinc in the upper of soybean plants showed that Hailun> Fangzheng> Shuangcheng, it may be due to the adsorbability of shuangcheng was strongger than Fangzheng and Hailun, which resulted in the decrease of the transference amount of copper to the above-ground in Shuangcheng, copper and zinc in the upper of soybean plants got rules that Hailun> Fangzheng> Shuangcheng.2 The residue of available Cu content in soil and the input of Cu content in soil were positively correlated, The residue of available Zn content in soil increased as Zn content inputted in soil increased.3 With the increase of concentration inputted in the soil, the residue of available Cu content in soil gradually increased, the contents of Cu and Zn in plant also increased correspondingly. When the same zinc concentration inputted, zinc content in plant were more than the residue of available Zn content in soil. 4 Copper and zinc adsorption increased as the increase consistency of copper and zinc in the equilibrium solutions of the soil, when Cu2+ and Zn2+ concentration were low in a equilibrium solution, the gradient of the adsorption curve was larger, it indicated that Cu2+ and Zn2+ in the solution most adsorpted by soil, but with the Cu2+ concentration in the equilibrium solution increased, the steep curve gradually became smaller, which indicated that the adsorption Cu2+ of the soil increased at a slower rate. With the Zn2+ concentration in the equilibrium solution increased, the curve lasted a period of platform areas when the concentration was about 10-30 mg·L-1 in the equilibrium solution, this showed that the adsor-ption Zn2+ of the soil increased at a slower rate, and then the gradient of the adsorption curve continue to increase.5 Cu2+ and Zn2+ adsorption ability in Shuangcheng, Hailun and Fangzheng got rules as follows:Shuangcheng>Fangzheng>Hailun, this may be due to the clay content of Shuangcheng>the clay content of Fangzheng>the clay content of Hailun, Shuangcheng soil had larger specific surface area, so Cu2+ and Zn2+ adsorption ability in Shuangcheng was stronger. The amount of copper in Shuangcheng, Fangzheng, and Hailun were 563,636,673 mg·kg-1, which indicated that environmental capacity of Cu2+ in Hailun was the largest.6 Freundlich equation could best describe adsorption-desorption processes of Cu2+ from the three framland black soil, Cu2+ desorbed had a obvious lag period, meanwhile, the desorption ratio of Cu2+ from the three framland black soil were low. Freundlich equation could best describe adsorption processes of Zn2+ from soil samples, but Langmuir equation could best describe desorption processes of Zn2+ from soil samples.
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