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Through planting Mustard in contaminated soil in XiaWujiang of HuanJiang County, fertilizing single conditioner and mixing three different conditioner hydrated lime, Bio-organic fertilizer and calcium magnesium phosphate. Study on the differences between the absorption ability of mustard and enrichments to heavy metal of improved soil in polluted area as well as heavy metal pollution’s impact on the yield and quality of mustard. By indoor cultivation experiment and plant mustard in greenhouse, research on the mustard’s biomass, heavy metal absorption, amount of heavy metals of rhizospheric and non-rhizospheric soil under fertilizing different conditioner, approach the differences and effects and mechanism of heavy metals contamination in soil improvement between single application and fertilizer. In order to evaluating the quality status and safety of mustard reasonably, providing a theoretical reference on vegetable cultivation and pollution prevention of contaminated soil, making a contribution to local people’s health and safety.The main results obtained are as follows:On the soil contaminated by lead, cadmium and zinc, the mustard which aren’t conducted with modifier are strongly affected. slaked lime, phosphate fertilizer and microbial organic fertilizer modifier can promote the growth of mustard, amend physicochemical property of soil and remit poisonous effect of the lead, cadmium and zinc, increase biomass. The best effect of modifier is slaked lime with microbial organic fertilizer.Using mixed fertilizer(slaked lime, phosphate fertilizer and microbial organic fertilizer)is better than using themselves respectively,and the aftereffect of slaked lime is no better than organic fertilizer and phosphate fertilizer, so the best choice is mixed slaked lime fertilizer and biological organic fertilizer together, it can not only amend heavy metal pollution of soil, but also can it keep effect for a long time.2.After adding slaked lime into the soil, OH- increase and mould as oxid deposition, when heavy metal’s available conformation decrease , the PH value of soil which was polluted by heavy metal is sharply increasing. So the PH value is a key factor of exchanging lead, zinc, cadmium in the soil. Different using of modifier can increase soil’s PH value in different degree. The best effect to raise soil’s PH value is using slaked lime, the effect order of improving soil’s PH is: slaked lime> microbial organic fertilizer>phosphate fertilizer.3.In the heavy metal polluted soil along the bank of DaHuan River, zinc and cadmium are mainly existing as free state form, lead is existing as organic matter form, modifier can notably cut down the effective form(exchangeable form) of heavy metal in soil, increase void form (Fe-Mn oxide and carbonate bound), thus lowering the bioavailability of heavy metals. Modifier of this effect is still the order of slaked lime> microbial organic fertilizer>phosphate fertilizer, Absorption effects are almost the same,so after adding the modifier, the main mechanism of modifier repairing heavy metal polluted soil is the decreasing of the effective form of heavy metal.
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