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通过盆栽实验研究了重金属Cu递进胁迫对白茅根际和非根际土壤酶活性的影响。结果表明,随着Cu浓度的增加,根际和非根际土壤的pH值下降、土壤酸化,而电导率呈持续上升,但根际土壤的pH值持续高于非根际土壤且更接近于中性。在梯度浓度的重金属Cu胁迫下,根际和非根际蔗糖酶活性随Cu浓度增加均表现出先升后降的趋势,但根际土壤的蔗糖酶活性在Cu浓度为1000 mg kg-1时达到峰值,而非根际土壤则在Cu浓度为500 mg kg-1时已到达峰值。白茅根际和非根际土壤中磷酸酶、脲酶和过氧化氢酶活性受Cu离子的影响均表现出持续下降的趋势,但各酶受抑制率各不相同。对梯度浓度Cu胁迫下的白茅根际和非根际土壤酶活性而言,四种酶在根际土壤中的活性普遍高于非根际土壤,且Cu2+对根际酶活性的抑制率也大于非根际土壤酶。对重金属单Cu污染敏感的土壤酶类依次为磷酸酶>蔗糖酶>脲酶>过氧化氢酶,其中磷酸酶可作为检测污染土壤的指示酶。
Pot experiments were conducted to study the effects of Cu progressive stress on Rhizosphere Rhizosphere and Rhizosphere soil enzyme activities in Rhizosphere. The results showed that with the increase of Cu concentration, the pH of rhizosphere and non-rhizosphere soil decreased and the soil acidified while the conductivity continued to increase. However, the pH of rhizosphere soil was higher than that of non-rhizosphere soil and closer to neutral. Under the gradient concentration of heavy metal Cu, the activities of invertase in rhizosphere and non-rhizosphere firstly increased and then decreased with the increase of Cu concentration, but the sucrase activity in rhizosphere soil reached at the concentration of 1000 mg kg-1 Peak, but not the rhizosphere soil peaked at a Cu concentration of 500 mg kg-1. The activities of phosphatase, urease and catalase in rhizosphere and non-rhizosphere rhizosphere of Rhizoma Imperatae showed a continuous decreasing trend under the influence of Cu ions, but the inhibition rate of each enzyme was different. The activity of four enzymes in rhizosphere soil was higher than that in non-rhizosphere soil under rhizosphere and non-rhizosphere soil enzymes under the gradient Cu stress, and Cu2 + had more inhibitory effect on Rhizosphere enzyme activity Non-rhizosphere soil enzymes. Soil enzymes susceptible to single Cu heavy metal pollution were phosphatase> sucrase> urease> catalase, of which phosphatase could be used as an indicator enzyme for the detection of contaminated soil.