艾比湖湿地自然保护区4种典型群落间土壤酶活性的变化

Variation of Soil Enzyme Activity among Four Typical Plant Communities in the Ebinur Lake Wetland Nature Reserve,Xinjiang

酶是土壤生态系统代谢的一类重要动力,研究其在土壤垂直层间和群落间的变化,能够为理解土壤生态系统中物质循环和能量转换提供依据。本文以艾比湖湿地自然保护区内分布最广泛的胡杨、梭梭、柽柳和盐节木4种典型荒漠群落为研究对象,通过分析过氧化氢酶、脲酶、磷酸酶和蔗糖酶的活性、群落数量特征和土壤理化性质在不同群落间的变化,试图阐明群落数量特征和土壤理化因子对土壤酶活性变化的影响。结果表明:(1)4种典型群落内,土壤酶活性在0~15 cm、15~30 cm和30~50 cm的土层间均无显著性差异(P>0.05);(2)4种典型群落间,同土壤深度的过氧化氢酶和磷酸酶的活性均无显著性差异(P>0.05);相反,同土壤深度的脲酶和蔗糖酶的活性存在显著性差异(P<0.05);(3)将群落数量特征和土壤理化因子对土壤酶活性逐步回归后发现,除过氧化氢酶活性受群落数量特征影响外,脲酶、蔗糖酶、磷酸酶的活性变化均与群落数量特征无关。表明干旱荒漠内,群落数量特征和土壤理化因子都能对土壤酶活性的变化产生影响,但具体起影响作用的因子与土壤酶类型有关。

Soil enzyme is an important driving force for metabolic process of soil ecosystem,its change among soil layers and among plant communities can help us to understand the material cycle and energy conversion of soil ecosystem. In this study,four typical plant communities,i. e. Populus euphratica,Haloxylon persicum,Tamarix chinensis and Halocnemum strobilaceum communities,were set as the research subjects,and subsequently the variations of soil enzyme activities,i. e. catalase,urease,phosphatase and invertase,and the soil physicochemical properties and community quantity characteristics were investigated so as to reveal the relationships among them. The results are as follows：（1） Soil enzyme activities were not significantly different among soil layers of 0-15,15-30 and 30-50 cm in depth in the four typical communities（P〉 0. 05）;（2） There were no significant changes of activities of catalase and phosphatase among the four typical communities at the same soil depth（P 〉 0. 05）,whereas the urease and invertase activities were opposite（P 〈 0. 05）;（3） The results of multivariate linear stepwise regression revealed that there were little relations between the activities and community quantity characteristics for other soil enzymes except for the variation of catalase activity influenced by community quantity characteristics. In conclusion,soil physicochemical properties and community quantity characteristics can affect the changes of soil enzymes activity across soil layers and plant communities,however,the essential factors affecting soil enzyme activity was related to soil type.