元谋干热河谷植被恢复对土壤酶活性的影响特征

Effects of Vegetation Restoration on Soil Enzyme Activity in Yuanmou Dry-hot Valley,China

选取5种植被恢复模式,研究了不同模式对土壤酶活性的影响以及土壤肥力与土壤酶活性的关系。结果表明,植被恢复后土壤蔗糖酶、过氧化氢酶和碱性磷酸酶活性相比光板地都有明显提高,顺序依次为酸角>小桐子>印楝;同种植被的土壤酶活性表现出根际大于非根际的特性;不同的植被恢复模式和种植方式对酶活性都有较大的影响,等高垄沟模式具有较好的保土保肥能力,创造了良好的微生物环境,增强了土壤酶活性;植被恢复模式下酶活性与土壤肥力之间的关系密切,特别是有机质、全氮与土壤蔗糖酶、过氧化氢酶和碱性磷酸酶的相关性较好。因此,用土壤酶活性来评价植被恢复的效果是可靠的。

The soil enzyme is a key criterion for evaluating soil efficiacy of vegetation restoration,as it is an important indicator of soil quality and function.The objectives of this study are 1）to estimate the effects of vegetation restoration on soil enzyme activity,2）to determine the correlationship between soil fertility and enzyme activity by comparing the five alternatives of vegetaion restoration.The results showed that soil enzyme activity of sucrase,catalase and alkaline phosphatase activity had significantly increased after vegetation restoration than that of barren land,and its magnitude followed the order of TamarindusJatrophacurcas L.Azadirachta indica.The soil enzyme activity in the rhizosphere of hedge acacia and Azadirachta indica was higher than in non-rhizosphere.Countour planting was found having an important role in preserving soil fertility to create a favorable environment for microorganisms and to enhance soil enzyme activity.These results suggested that different vegetation restoration practices and planting methods had distinct influences on soil enzyme activity.The enzyme activity had closely related with the soil fertility for various vegetation restoration practices,particularly for the relationship between soil organic matter,total nitrogen and soil sucrase,catalase and alkaline phosphatase activity.Thus,we concluded that indicator of soil enzyme activity was reliable for efficiency assessment of vegetation restoration.