三江平原小叶章湿地土壤酶活性的季节动态

选取三江平原小叶章（Calamagrostis angustifolia）沼泽湿地为研究对象,于5—9月采集0～20cm土壤样品,分析了小叶章湿地土壤酶活性的季节动态变化,并探讨了其与土壤有机碳和全氮含量的关系。结果表明：小叶章湿地土壤脲酶、蔗糖酶、淀粉酶、纤维素酶、酸性磷酸酶、过氧化氢酶活性具有明显的季节变化特点,变异系数分别为13.1%、7.9%、13.6%、9.8%、5.0%、27.0%。土壤脲酶、蔗糖酶、酸性磷酸酶、过氧化氢酶、纤维素酶活性具有相似的动态规律,均在6月份出现一个波峰值,但最大值出现的月份不同,脲酶、蔗糖酶、纤维素酶在9月份时的酶活性最高,而酸性磷酸酶和过氧化氢酶在6月份时酶活性最高。淀粉酶活性动态规律表现为5—7月酶活性降低,而后酶活性升高,9月份酶活性最高,此时淀粉酶的水解能力最大。并且,随着季节变化,小叶章湿地土壤脲酶、蔗糖酶、纤维素酶活性与有机碳含量显著正相关（p〈0.05）,淀粉酶、酸性磷酸酶活性与土壤全氮含量显著正相关（p〈0.05）。

Seasonal dynamics of soil enzyme activities under Calamagrostis angustzfolia marsh in the Sanjiang Plain

Surface soil samples（0～20 cm）were collected from the Calamagrostis angustifolia marsh in the Sanjiang Plain from May to September and soil enzyme activities were analyzed aiming to reveal their seasonal dynamics characteristics and their correlation-ships with the soil organic matter and nitrogen contents.The results indicated that the activities of urease,invertase,amylase,cellu-lase,acid phosphatase,catalase had significant seasonal variations,and coefficients of variation were 13.1%,7.9%,13.6%,9.8%, 5.0%,27.0%,respectively.The activities of soil urease,invertase,acide phosphatase,catalase and cellulase were with similar dy-namic rules and appeared peak values in June,but the maximum occured in different months.The activities of urease,invertase,cel-lulase were highest in September,while the activities of acid phosphatase and catalase were highest in June.The seasonal change of amylase activity was different from other enzyme activities,which firstly decreased rapidly from May to July,and then increased gradually and maximum value of amylase activity was in September.It showed that the hydrolysis intensity of amylase was the strongest at this period.Correlation analysis suggested that the activities of soil urease,invertase,cellulase under Calamagrostis an-gustifolia marsh were significantly positive related to the content of soil organic carbon（p0.05）and acid phosphatase activity was significantly positive correlation with the content of soil total nitrogen（p0.05）with the variation of season.