锌铬复合胁迫对大豆根际土壤酶活性的影响

为研究不同Zn、Cr复合胁迫对大豆根际土壤酶活性的影响,在盆栽条件下,采用添加外源Zn、Cr的方法,测定了大豆根际和非根际土壤脲酶活性、过氧化氢酶活性、蔗糖酶活性。结果表明,不同Zn、Cr处理对大豆根际土壤脲酶活性有显著抑制效果,在Zn、Cr浓度分别为500、400 mg/kg时,大豆根际土壤脲酶活性为最低。随Zn、Cr浓度的增加,大豆根际土壤过氧化氢酶活性呈现先升高后降低的趋势,在Zn、Cr浓度分别为0、300 mg/kg时,达最大值,比对照提高14.80%;在Zn、Cr浓度分别为500、400 mg/kg时,仅为2.38 ml/(g·h),是最小值,比对照降低44.38%。随Zn、Cr浓度增加,大豆根际土壤蔗糖酶活性也呈现类似趋势,在Zn、Cr浓度分别为0、90 mg/kg时,达最大值3.65(mg/g·d),比对照提高9.87%;在Zn、Cr浓度分别为500、400 mg/kg时,达到最小值1.80(mg/g·d),比对照降低45.8%。同时结合偏相关分析结果发现,Zn、Cr对3种土壤酶活性均产生了协同抑制效应,且Zn的抑制作用大于Cr。

Effects of Compound Pollution of Zinc (Zn) and Chromium (Cr) on Soil Enzyme Activities of Soybean Rhizosphere

To study the different concentrations of zinc and chromium on soybean roots soil enzyme activities, a pot experiment was carried out using the addition of exogenous zinc and chromium method for determining soil urease activity, soil catalase activity and soil sucras activity on roots zone of soybean. The results showed that different zinc and chromium concentrations had significant inhibitory effect on soil urease activity on roots zone of soybean. When zinc and chromium concentrations were 500 mg?kg-1, 400 mg?kg-1 respectively, soil urease activity was lowes. With increasing concentrations of zinc and chromium, soil catalase activity on roots zone of soybean increased firstly and then decreased, the maximum was in 0 mg?kg-1zinc and 300mg?kg-1chromium, which increased 14.80% compared with the control. When the concentrations of Zn and Cr were 500 mg?kg-1, 400 mg?kg-1respectively, soil catalase activity on roots zone of soybean rhizosphere only 2.38 ml?g-1?h-1 (the minimum), and which was 44.38% lower than the control. With zinc and chromium concentrations increased, soil sucras activity on roots zone of soybean also showed a similar trend with soil catalase activity. When zinc and chromium concentrations were 0 mg?kg-1, 90 mg?kg-1respectively, soil sucras activity reached a maximum of 3.65 mg?g-1?d-1, and was increased by 9.87% compared with the control. When zinc and chromium concentrations were 500 mg?kg-1, 400 mg?kg-1respectively, soil sucras activity reached minimum of 1.80 mg?g-1?d-1, and was 45.8% lower than the control. Combined with partial correlation analysis, found that zinc and chromium had synergistic inhibitory effect on three kinds of soil enzyme activities, and the effect of zinc was higher than chromium.