黄土丘陵区不同植被恢复模式对土壤酶活性的影响

为了解侵蚀环境下植被恢复对土壤酶活性的影响，以典型侵蚀环境黄土丘陵区纸坊沟流域生态恢复30a植被长期定位试验点为研究对象，选取坡耕地为参照，分析了植被恢复过程中土壤脲酶、磷酸酶、蔗糖酶、淀粉酶、纤维素酶、过氧化氢酶、多酚氧化酶及理化性质的演变特征。结果表明，黄土丘陵区的坡耕地由于不合理的人为干扰，土壤理化性质和酶活性较弱，通过植被恢复可以有效的改善土壤肥力，不同恢复模式对土壤酶活性和肥力的改善作用不同，恢复30a，脲酶活性增加33%~213%，磷酸酶活性增加275%~394%，蔗糖酶活性增加70%~210%，纤维素酶活性增加24%~48%，过氧化氢酶增加32%~96%，多酚氧化酶降低23%~29%，淀粉酶变化规律不同。不同植被恢复模式其生物特性不同，对土壤酶活性影响也不同。相关性分析说明磷酸酶、蔗糖酶、纤维素酶和多酚氧化酶与其它因子相关性相对较强，可以作为评价土壤质量的生物学指标。

Efect of Soil Enzyme Activities under Different Vegetation Restoration in Eroded Hilly Loess Plateau

In order to find the effect of soil enzyme activities under different vegetation restoration in Hilly Loess Plateau, seven kinds of soil enzyme activities and physicochemical properties were studied. In this study, six long trial sites located in Zhifanggou Catchment were studied, and a farmland was chosen as the references. The results showed that soil physical and chemical properties were poor in slope farmland, but vegetations recovery can increased them apparently. After 30 years of de-farming and vegetation recovery, soil urease, phosphatases, invertase, cellulose and catalase, respectively, increased by the percentage of 33%~213%, 275%~394%, 70%~210%, 24%~48% and 32%~96% as compared to the farmland, while polyphenol oxidase decreased by the percentage of 23%~29% and amylase had no obvious effect. Different types of vegetation restoration are different in improving soil enzyme activities. The significant relationships were observed between phosphatase, invertase, cellulose, polyphenol oxidase and physical and chemical properties of soil. We think that the four kinds of soil enzyme activities can be used as indicators of soil quality.