阿拉尔垦区土壤理化因子与酶活性的通径分析

Path Analysis of Soil Physicochemical Properties and Enzymatic Activities in the Aler Reclamation Area

土壤酶活性可以反映土壤生物化学过程的方向和强度。以新疆塔里木河上游阿拉尔垦区作为研究区域,选择8a棉田、30a棉田、人工林、天然林、荒草地、撂荒地及盐碱地等不同土地利用方式的样地为研究对象,综合考虑土壤理化和酶活性指标,对这两者的相关性进行深入探讨。结果表明:酶活性的较高值出现在绿洲内部的人工林、天然林和8a棉田,较低值出现在盐碱地和荒草地。由通径分析及决定系数可知,全氮是影响该地区酶活性的主导因子;速效磷对脲酶和转化酶存在显著的直接正效应,是影响脲酶和转化酶活性的主导因子;速效钾是影响过氧化氢酶和转化酶活性的重要因素。与简单相关或多元回归分析方法相比,通径分析能对土壤理化性质和土壤酶之间的关系进行更客观、全面地解释。

Soil enzyme activity can reflect the direction and strength of soil biochemical processes.The Aler reclamation area of upper reaches of Tarim River was selected as the study area.We chose sample plots of different land use type as the research sites including 8-year cotton field,30-year cotton field,forest plantation,natural forest,grassland,abandoned land,and saline-alkali land,soil physicochemical property and the enzyme activity indices were considered,and the correlations between the soil physicochemical property and the enzyme activity of the Aler reclamation area were further discussed.The results showed that the enzymatic activities were higher in forest plantation,natural forest and 8-year cotton field while lower in saline-alkali land and abandoned land.Path analysis and determination coefficient showed that total nitrogen was the dominant factor affecting the soil enzyme activity in the region.The available P directly influences urease and invertase activities,and the available K was the main factor affecting catalase and invertase activities.Compared with simple correlation and multiple regression analysis method,path analysis could more objectively and comprehensively explain the relationships of soil enzyme activities and soil physicochemical properties.