艾比湖自然保护区土壤酶活性及理化性质

以艾比湖自然保护区荒漠生态系统不同土壤类型为研究对象，分析各土壤类型酶活性及理化性质，探讨理化性质对酶活性影响的强度。结果表明：黑钙土酶活性较高，营养元素丰富，水分和盐分条件较好；而棕漠土、栗钙土酶活性相对较低，理化条件相对较差；灰钙土、灰漠土则表现为土壤酶活性极差，营养元素贫乏。从通径分析和决定系数得出：土壤有机质是影响该地区酶活性的主导因子；速效磷对过氧化氢酶活性的直接通径系数较大，较大程度影响过氧化氢酶活性；全氮对脲酶活性直接通径系数较大，是直接影响脲酶活性的主导因子；碱解氮对磷酸酶和蔗糖酶活性有强烈的直接作用，是影响磷酸酶和蔗糖酶活性的主导因子；土壤总盐对蔗糖酶存在较大的直接负效应，是制约蔗糖酶活性的主导因子。

Enzyme Activities and Physicochemical Properties of Soils in the EbinurLake Nature Reserve in Xinjiang,China

In this paper, the influence intensity of soil physicochemical properties on soil enzyme activities was studied with the methods of correlation analysis and path analysis based on analyzing 4 soil enzymatic activities including catalase, urease, invertase and alkaline phosphatase and 7 soil physicochemical properties including soil moisture content, total salt content, pH value, organic matter content, total N content, available phosphorus content, and available nitrogen content of different soils in a typical desert ecosystem in the Ebinur Lake Nature Reserve. The results showed that soil enzyme activities and physicochemical properties were obviously different from the five soil types. Specifically, the soil enzyme activities and physicochemical properties of chernozem soil were better than those of other soils. Path analysis revealed that soil organic matter content was the leading factor affecting soil enzyme activity; available phosphorus content was the main factor affecting soil catalase activity and had the maximum path coefficient and determinative coefficient; soil total nitrogen content was the decision factor of urease activity and had the highest direct path coefficient; available nitrogen content had the intensive effects on invertase and phosphatase activities; soil total salt content was the main factor of restricting soil invertase. Compared with correlation analysis and stepwise regression analysis, path analysis could be used to objectively and comprehensively assess the influences of soil physicochemical properties on soil enzyme activity.