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In this paper, rice (Oryza sativa L.) as the research object, through artificial cultivation of zinc chromium complex by adding four kinds of contaminated soil improver: organic amendments (straw, manure) and inorganic modifier (superphosphate, lime ), respectively for each modifier high (straw, manure and superphosphate as 8g/kg, quicklime is 1.5g/kg), medium (straw, manure and superphosphate as 6g/kg, quicklime is 1.0g/kg), low (straw, manure and superphosphate as 4g/kg, quicklime is 0.5g/kg) concentration process, Sichuan Agricultural University farm in pot experiment studied systematically applied into the soil improver zinc, chromium and nutrients (N, P, K) content changes, and different amendments on rice at different growth stages (tillering, booting and filling stage), root (root within the root surface adsorption and accumulation) zinc, chromium content and impact of changes in nutrient absorption, zinc chromium complex contaminated soil on rice production safety and provide a scientific basis for soil remediation, the main findings are as follows: 1. at different growth stages of rice, in addition to different concentrations of superphosphate treatment did not reduce soil available zinc content, the straw, manure and lime treatment with different concentrations were reduced soil available zinc content, in which high concentrations of lime most significant effects of treatment, the soil available Zn respectively, over the same period were reduced 77.51%, 42.28% and 69.18%. Soil available chromium content is processed at high concentrations straw reaches a minimum, respectively, over the same period were reduced 33.69%, 27.25% and 39.78%, while the chicken manure, superphosphate and lime treated with different concentrations, there is no this apparent results. Description lime, straw straw were high concentrations of reducing soil available zinc, chromium content, improved contaminated soil has an important role. 2 different growth stages in rice, soil nitrogen content maximum occurred at high concentrations of manure treatment, respectively, over the same period was increased by 148.03%, 176.26% and 119.39%; maximum soil available potassium occurred at high concentrations of straw treatment, whereas the maximum soil available phosphorus content appears in high concentrations superphosphate processed. Description manure, straw and superphosphate handle high concentrations of rice at different growth stages for the improvement of different soil nutrient availability plays an important role in promoting. 3 tillering in rice, wheat straw treatment on the root surface with a high concentration of zinc adsorption and zinc accumulation in roots sharpest decrease, respectively, over the same period were 61.62% and 52.11% lower. At booting and filling stage of rice, chicken rice roots treated with high concentration of zinc decreased the most. Among them, the root surface adsorption of zinc and zinc accumulation in roots were lower than the same period were 30.84%, 38.32% and 60.72%, 70.24%. The chromium content in rice roots maximum and zinc content in rice roots showed a similar trend. This shows that two types of modifiers (organic and inorganic), the organic (straw, manure) amendments on rice roots zinc, chromium adsorption capacity and the roots of zinc, chromium accumulation has produced significant effect, visible organic improver is mainly through direct effect on rice roots to reduce its zinc, chromium absorption. 4 in the tillering and booting, total nitrogen content in rice roots straw treatment showed high concentrations of the maximum, in which nitrogen adsorption capacity and root surface roots absorb the maximum amount of nitrogen respectively, compared with the same period of comparison High 203.37%, 49.81% and 202.38%, 35.25%. Filling stage in rice, rice root nitrogen content in the manure treatment showed high concentrations of the maximum, which, roots and root nitrogen adsorption nitrogen uptake within the maximum height respectively, compared with 68.8% in the same period of comparison and 68.64%. Rice Root maximum total potassium and total nitrogen in rice roots trend consistent performance. The roots of total phosphorus in high concentrations superphosphate treatment showed maximum. Visible, organic amendments and inorganic modifier application can increase soil nutrient availability content, improve rice root active absorption of nutrients, and promote the growth of rice roots.
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