| 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0，50，100，300，500，1 000，1 500，3 000 mg/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 25 mg/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。 |
| 关键词: Cr3+ 土壤酶 生态剂量 作用机理 总体酶活性 |
| DOI： |
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| 基金项目: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） |
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| Effects of Cr3+ on soil enzyme activity |
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HU Yi,KONG Long,HE Wenxiang,et al
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Northwest A&F University
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| Abstract: |
| 【Objective】Influence of Cr3+ 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 (ED10),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. |
| Key words: Cr3+ soil enzymes ecological dose mechanism total enzyme activity |
