塔里木盆地南缘绿洲土壤酶活性与理化因子相关性

基于塔里木盆地南缘于田绿洲土壤酶活性与水盐、养分等理化因子数据,利用冗余分析技术(RDA)全面分析了土壤酶活性与理化因子间的关系. 结果显示:①于田绿洲土壤酶活性总体水平较低,过氧化氢酶(以KMnO₄计)、转化酶(以Na₂S₂O₃计)、脲酶(以NH₃-N计)和碱性磷酸酶(以C₆H₆O计)活性平均值分别为9.37、2.04、0.27和0.18 mg/g；研究区土壤水分含量(15.46%,以w计)较少且盐渍化严重〔w(全盐)平均值为19.39 g/kg〕. ②w(有机质)、土壤水分含量、地下水埋深和w(有效磷)是影响土壤酶活性的主要因素,w(有机质)、土壤水分含量、w(有效磷)与土壤酶活性呈正相关,地下水埋深与土壤酶活性呈负相关. ③各理化因子对土壤酶活性影响的重要性排序为w(有机质)、土壤水分含量、地下水埋深、w(有效磷)、pH、w(全盐)、电导率、w(速效钾). 综合分析表明,研究区强盐渍化的土壤性质对土壤酶活性的抑制并不显著,土壤碳、磷等养分与水分状况才是限制土壤酶活性的关键因素. 

Soil Enzyme Activities and Their Correlation with Physicochemical Factors in the Oasis of Southern Margin of Tarim Basin

To investigate the relationships between soil enzyme activities and physicochemical factors, soil enzyme activities and physic chemical factors were studied in Yutian oasis of southern marginal zones of Tarim Basin by traditional statistics and redundancy analysis (RDA). The results showed that soil enzyme activities in the area were low, with the average of enzyme properties as follows:catalase (calculated by KMnO₄), invertase (calculated by Na₂S₂O₃), urease (calculated by NH₃-N), alkaline phosphatase (calculated by C₆H₆O) activity of 9.37,2.04,0.27 and 0.18 mg/g, respectively. According to the RDA results, the soil organic matter content, water content, groundwater depth and available phosphorus were the main factors limiting soil enzyme activities. Soil organic matter, water and available phosphorus were significantly positively correlated with enzyme activity, while groundwater depth was negatively correlated with enzyme activity. According to the ranking and significant test, the importance rank followed the order as follows:soil organic matter content > soil water content > groundwater depth > available phosphorus > pH > conductivity > available potassium. Strong soil salinization was not entirely limited to soil enzyme activities; organic matter, water and nutrients were found to be the key factors limiting enzyme activities.