For the purpose of ameliorating sediment and changing it into the kind of soil suitable for plant growth, straw, withered leaves and sediment were minxed uniformly, and the compost was kept standing for 70 days. The analysis results showed that, after composting, the acid-soluble heavy metals concentration in the sedi-ment decreased obviously, and the concentrations of oxidable heavy metals and residual form heavy metals in-creased, therefore, the bio-availability and transfer ability were effectively reduced, which was conducive to the safe use of sediment. In addition, the density of the sediment decreased with the increasing of apparent density;the concentration of organic matters increased obviously, and the total nitrogen concentration reduced slightly;the rapid available phosphorus concentration remained unchanged; the microorganism concentration was enhanced significantly. The result of pot experiment showed that, the modified sediment was appropriate for water spinach growth, the yield of water spinach planted in the said sediment was higher than that in local farm-oriented soil, the content of Pb, Cu and Cd in the water spinach was lower than the national standard. It could draw a conclu-sion that, sediment contaminated by heavy metals could be impolyed as vegetative soil after compost.%以传统堆肥方式将秸秆、枯树叶与底泥混合均匀,静置堆肥70 d,改良底泥,制作成适合植物生长的土壤。分析结果表明,堆肥后的底泥中酸可提取态重金属含量明显降低,可氧化态、残渣态重金属含量增加,有效地降低了重金属生物有效性和迁移能力,提高了底泥利用的安全性；底泥的密度降低、表观密度增大；底泥中有机质明显增加,总氮略有降低,速效磷含量基本不变；微生物量有显著提高。盆栽试验结果表明,改良后的底泥适宜蕹菜的生长且产量高于当地农用土蕹菜产量,蕹菜中Pb、 Cu、 Cd的含量低于国家标准。重金属污染底泥经过堆肥改良后可以作为培植土利用。
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