扎龙湿地土壤微生物代谢功能的季节性差异

Seasonal discrepancy of metabolic function of soil microbial communities in Zhalong wetland

运用Biolog-Eco微平板技术,对扎龙湿地不同季节(春、夏、秋和冬)的土壤微生物群落代谢功能多样性进行研究。结果表明:不同季节土壤微生物群落代谢活性差异显著(P<0.01),微生物碳源平均颜色变化率(average well color development,AWCD)主要表现为夏季>秋季>春季>冬季。不同季节湿地微生物群落Shannon指数和Simpson指数均为夏季最高,其次为春季,秋季、冬季间无显著差异(P>0.05);而McIntosh指数为夏季最高,其次为春季,秋季最低。主成分分析(principal component analysis,PCA)表明,湿地微生物碳代谢功能具有显著的季节变化,聚合物类和糖类是区分不同季节湿地微生物代谢功能差异的主要碳源类型。土壤养分因子很好地解释了微生物功能的季节性差异,对微生物代谢功能多样性有重要的影响,其中有机质、速效氮和总磷是影响土壤微生物代谢功能的主要因素。

Biolog-Eco plate analysis was used to study the metabolic functional diversity of soil microbial communities of different seasons（spring,summer,autumn and winter）in Zhalong wetland.The results showed that the metabolic activity of soil microbial communities in different seasons significantly varied with each other（P 0.01）.The average well color development（AWCD）values were changed in the following order：summerautumnspringwinter.The Shannon index and the Simpson index were both the highest in summer,followed by the spring,and there was no significant difference between autumn and winter（P0.05）.The McIntosh index was the highest in summer,followed by the spring,and the lowest in autumn.Principal component analysis（PCA）revealed that the carbon metabolism functional diversity of wetland soil microbial communities had significant seasonal changes and polymers and carbohydrates were the main carbon source types to distinguish the differences between the metabolic function of wetland soil microbial communities of different seasons.Soil nutrient factors explained the seasonal discrepancy of microbial function,which had important influence on metabolic functional diversity of microbial communities.The organic matter,available nitrogen and total phosphorus were the main factors influencing the metabolic function of soil microbial communities.