重金属镉对土壤酶活性影响的研究

在试验室条件下,研究了外源添加不同浓度的重金属镉对土壤生物活性和土壤酶活性的影响.结果表明,重金属镉污染对不同的土壤生化过程具有不同效应,镉污染对土壤酶活性的影响中,对土壤的脲酶活性有很显著的抑制作用,而对过氧化氢酶、磷酸酶等活性影响较小.通过对土壤酶活性的测定得出,由于土壤脲酶对不同浓度镉表现强烈的敏感性,用脲酶作为土壤Cd污染的评价指标和制定Cd的临界含量是可行的,可为污水灌溉地区提供土壤中镉浓度的最高限值,保证污灌区的农作物食用安全和土壤的可持续利用,对地区的经济发展和环境安全有重要意义.

Influence of heavy metal Cadmium on the soil enzyme activity

Under the laboratory condition,the influence on the soil biological and enzyme activity was studied by adding different concentration of heavy metal Cadmium.The results indicate that,for different soil biochemical process,the pollution effects of heavy metal Cadmium are different.The cadmium pollution has strong inhibitory action to the soil urease activeness,but has only a little influence on oxidized hydrogen enzyme and phosphatase.The determination of soil enzyme activity shows that it is feasible that urease activeness can be used as the evaluating indicator of soil Cd pollution and the critical content of Cd,as the enzyme urease in soil is very sensitive to Cd with different concentrations.It may provide the highest limiting value of the cadmium＇s concentration to the sewage irrigation areas,which guarantees the safe crops and sustainable soils.The study has the vital significance to the local economical development and the environmental safety.