外源Cd对不同利用方式红壤脲酶活性的影响

采用室内培养实验,通过将外源Cd添加到同一母质、全镉含量相近的不同利用方式的红壤中(林地、水稻土和菜园土),研究了外源Cd污染对不同利用方式红壤脲酶活性的影响。结果表明:整个培养过程中,Cd污染对3种红壤脲酶活性都有抑制作用,且随重金属浓度的增强而增强。同剂量Cd污染对3种红壤脲酶活性的抑制效应不同,大小为林地>水稻土>菜园土。实验设定的Cd处理水平下,对林地、水稻土和菜园土脲酶活性产生显著抑制作用(p<0.05)的Cd浓度分别为5、30和50 mg/kg土。

Effects of cadmium pollution on urease activities in red soils of different utilizations

With an indoor incubation experiment,the effects of applied cadmium(Cd) on the urease activities in forest,paddy and garden soils of the same soil parent materials,the nearly Cd contents and different utilizations were studied.The results indicated that during the whole incubation period,Cd pollution had significant inhibitory effects on the urease activities in the three tested soils and the effects increased with their increasing concentration.Compared with the effects in the three tested soils,Cd had higher inhibitory effect on urease activities in forest soil than in paddy soil and garden soil.Under the same level Cd pollution,the inhibitory effects on the urease activities were in the order: forest soil>paddy soil>garden soil.Under designed test conditions,Cd pollution had remarkable effects(p<0.05)on urease activities in forest soil,paddy soil and garden soil when the concentrations of Cd were 5,30 and 50 mg/kg,respectively.