Cr^(3+)的土壤酶效应研究  

Effects of Cr^(3+) on soil enzyme activity

作　　者：胡一[1] 孔龙[2] 和文祥[1] 吕家珑[1] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]西北农林科技大学生命科学学院,陕西杨凌712100

出　　处：《西北农林科技大学学报（自然科学版）》2012年第5期166-172,共7页Journal of Northwest A&F University(Natural Science Edition)

基　　金：公益性行业(农业)科研专项"主要农产品产地土壤重金属污染阈值研究与防控技术集成示范"(200903015);国家"863"计划项目"农业生境监测检查与修复技术研究"(2012AA100602)

摘　　要：【目的】研究Cr3+对土壤酶活性的影响,为建立土壤重金属铬污染评价的酶学指标提供依据。【方法】以我国常见的红壤(酸性土壤)及褐土和风沙土(碱性土壤)为供试土样,采用室内模拟方法,在供试土样中添加0,50,100,300,500,1 000,1 500,3 000mg/kg Cr3+,研究不同Cr3+含量下土壤脲酶、磷酸酶、芳基硫酸酯酶、过氧化氢酶、脱氢酶和总体酶活性的变化规律。【结果】Cr3+显著或极显著地抑制了土壤脲酶、磷酸酶、芳基硫酸酯酶、过氧化氢酶和脱氢酶活性,且均为完全抑制作用(包括竞争性抑制和非竞争性抑制),供试土样中Cr3+轻度污染时的生态剂量(ED10)为25mg/kg;酸性土壤中脲酶、芳基硫酸酯酶和过氧化氢酶对Cr3+的毒害反应更敏感,碱性土壤中磷酸酶和脱氢酶的反应更敏感。【结论】土壤脲酶、磷酸酶、芳基硫酸酯酶、过氧化氢酶、脱氢酶活性及总体酶活性均可用来表征土壤Cr3+污染程度的大小;土壤pH、有机质含量对土壤酶与Cr3+的关系具有重要影响。[Objective] Influence of Cra＋ on soil enzymes was studied to provide a foundation for enzyme assessment index in soils polluted by heavy metals. [Method] Red soil,Cinnamonl and sandy soil, main soil types in China, were sampled. By simulative method, soil urease, phosohatase, arylsulphatase, catalase,dehydrogenase and total enzyme activities were studied under different Cr3＋ concentrations 0,50, 100,300,500,1 000,1 500,3 000 mg/kg. [Result] Soil urease, phosohatase, arylsulphatase, catalase, dehydrogenases enzymes significant or remarkably significant negative correlation with Cr3＋ concentrations was obtained. And the reaction mechanism was complete inhibition（including competitive inhibition and noncompetitive inhibition）. The critical Cr3＋ concentration was 25 mg/kg when the soils were slightly polluted （ED1o） ,arylsufatase and catalase were more sensitive to Cr3＋ in acid soils,however,in alkalinen soil phosohatase and dehydrogenases were more sensitive. [Conclusion] Soil urease, phosohatase, arylsulphatase, catalase,dehydrogenases enzymes and total enzyme activity could be index to monitor soils polluted by Cr3＋ , soil enzyme impact was up to soil physic-chemical properties,such as pH and organic matter content.

关 键 词：CR3+ 土壤酶 生态剂量 作用机理 总体酶活性 

分 类 号：S154.2[农业科学—土壤学]