ABSTRACT

Innovative biological processes that utilize the power of microorganisms are interesting tools for the treatment of Heavy metals polluted soils. This study conducted in column systems containing three different soils artificially contaminated with Cr, Zn and Cu, investigates the effect of soil bioaugmentation by two yeast strains Wickerhamomyces anomalus and Candida tropicalis on heavy metal leaching and the behavior of soil enzymatic activities. The soils have different capacity to retain heavy metals and the correlation tests showed the influence of soil properties, mainly CaCO₃, clay, silt and aromaticity of organic matter on the mobilization of these heavy metals. Strong positive correlation was also observed between enzymes activities (phosphatase, galactosidase and arylsulfatase) and organic matter. The introduction of yeast strains was beneficial. It favored the immobilization of Cr and the mobilization of Cu and Zn in soils. It also stimulated the soil phosphatase, galactosidase and arylamidase activities and affected negatively arylsulfatase activity. Data thus indicate that the bioaugmetation of soils with yeast cells present an excellent performance in bioremediation by decreasing/increasing the bioavailability of metals and on soil ecosystem functioning by increasing soil enzyme activity.

摘要

利用微生物的力量进行创新的生物过程是处理重金属污染土壤的有趣工具。这项研究是在含有三种分别被Cr，Zn和Cu人工污染的土壤的色谱柱系统中进行的，研究了两种酵母菌株Wickerhamomyces anomalus和热带假丝酵母对土壤生物强化对重金属浸出的影响以及土壤酶活性的行为。土壤具有不同的保留重金属的能力，相关测试表明土壤性质的影响主要是CaCO _3。，粘土，淤泥和有机物的芳香性对这些重金属的动员。酶活性（磷酸酶，半乳糖苷酶和芳基硫酸酯酶）与有机物之间也观察到强正相关。酵母菌株的引入是有益的。它有利于土壤中铬的固定以及铜和锌的固定。它还刺激了土壤磷酸酶，半乳糖苷酶和芳基酰胺酶的活性，并对芳基硫酸酯酶的活性产生了负面影响。因此，数据表明，通过降低/增加金属的生物利用度，酵母细胞对土壤的生物强化在生物修复方面表现出优异的性能，并且通过增加土壤酶的活性对土壤生态系统起作用。