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近年来,国内外用污泥作肥料日趋增多。美国、日本、瑞典用于农田的污泥分别占25％、10％和1/3。上海每年也约有近百万吨污泥用于农田。而污泥中含有大量的有毒物质,特别是含有浓度很高、毒性很大的重金属。人们对镉的毒性研究,早在十九世纪中叶就开始了。但对作物因使用污水和污泥吸收重金属的研究,近几年才较为深入地开展起来。一、影响作物吸收镉的因素农田施用含镉污泥后,作物体内会不同程度地残留镉。然而由于土壤特性和作物种
In recent years, domestic and foreign sludge as fertilizer is increasing. The United States, Japan, Sweden sludge for farmland accounted for 25%, 10% and 1/3. Nearly 1 million tons of sludge are used in farmland each year in Shanghai. The sludge contains a lot of toxic substances, especially with high concentrations of toxic heavy metals. Cadmium toxicity studies began as early as the mid-nineteenth century. However, researches on crops that absorb heavy metals due to the use of sewage and sludge have only been carried out more thoroughly in recent years. First, the factors affecting crop absorption of cadmium Farmland containing cadmium sludge, the crop will be different degrees of residual cadmium. However, due to soil characteristics and crop species