镉胁迫下土壤理化因子与过氧化氢酶活性的通径分析

对湖南3种不同程度Cd污染土壤添加不同种类、不同浓度的修复材料，研究修复材料修复效果，并评估了Cd胁迫下土壤理化性质对过氧化氢酶的影响。分别对pH值、速效氮、速效磷、速效钾及土壤有效态Cd浓度与土壤过氧化氢酶活性做相关性分析、多元线性回归、通径分析，并对比3种分析。结果表明：Cd浓度较小的土壤过氧化氢酶活性的主要影响因子为土壤pH、土壤速效钾、土壤速效氮、土壤速效磷；中等污染土壤过氧化氢酶的主要影响因子为土壤速效氮、土壤速效磷；严重污染土壤过氧化氢酶的主要影响因子为pH值和土壤有效Cd。对比3种土壤影响因素的系数发现，随着土壤全Cd浓度的增加，土壤有效态Cd对土壤过氧化氢酶活性的影响系数越来越大，而土壤速效钾、土壤速效氮、土壤速效磷对过氧化氢酶活性影响系数越来越小。与简单相关和多元线性回归相比，通径分析结果能更客观、全面的体现各因素对土壤过氧化氢酶活性的影响过程。该试验为评价土壤性质对酶活性的影响提供依据。

Path Analysis of Soil Physicochemical Factors and Catalase Activities Under Cadmium Stress

To investigate the remediation effect of different soil repair materials and assess the impacts of soil physicochemical properties on catalase activities under Cd stress, this research added different kinds and different concentrations of repair materials into three different levels of Cd contamination soil in Hunan. The relations between catalase activities and pH value, available N, available P, available K, available Cd were studied through correlation analysis, multiple linear regression and path analysis. The results showed that pH value, available K, available N and available P were the major factors which influenced catalase activity in lower pollution soil; available N and available P were the major factors which influenced catalase activity in middle pollution soil; pH value and available Cd were the major factors which influenced catalase activity in serious pollution soil. With the Cd concentration increased in the soil, the influence coefficient of available Cd on catalase activities showed a growing trend, however, the influence coefficient of available K, available N and available P on catalase activities showed a reducing trend. Compared with the simple correlation analysis and multiple linear regression, path analysis results objectively and comprehensively explained the relationshipbetween soil catalase activity and soil physicochemical properties. This research could provide the foundation for accessing the effects of soil properties on enzyme activity.