湿地土壤微生物碳源代谢活性对不同水分条件的动态响应--以鄱阳湖为例  

Functional Response of Wetland Soil Microbial Carbon Source Metabolic Activity to Different Water Conditions——A Case of Lake Poyang

作　　者：刘亚军[1] 蔡润发 李赟璟 刘以珍[1] 葛刚[2] 吴兰[1] LIU Yajun;CAI Runfa;LI Yunjing;LIU Yizhen;GE Gang;WU Lan(School of Life Sciences of Nanchang University,Nanchang 330031,China;Key Laboratory of Environment and Resource Utilization of Poyang Lake,Ministry of Education,Nanchang 330031,China)

机构地区：[1]南昌大学生命科学学院,南昌330031 [2]鄱阳湖环境与资源利用教育部重点实验室,南昌330031

出　　处：《土壤》2018年第4期705-711,共7页Soils

基　　金：国家自然科学基金项目(31360127;31260110;31660149)资助.

摘　　要：为深入了解湿地土壤微生物群落代谢特征对不同水分条件的响应变化,本研究以鄱阳湖湿地表层土壤为研究材料,采用室内控制试验,运用Biolog技术探讨土壤微生物碳源代谢活性在不同水分条件(干燥、湿润、淹水)下连续处理132 d的变化特征。结果表明:湿润组土壤微生物代谢活性最高,其平均光密度值(AWCD)在处理的第72天分别是淹水组和干燥组的1.34倍和3.95倍;同时土壤微生物对不同碳源类型的利用能力也发生了显著的差异性变化,其中干燥组利用的主要碳源为多聚物类和碳水化合物类(占总碳源利用率的39.25%和36.53%),而淹水组对氨基酸类碳源有较高的利用能力(占总碳源利用率的36.33%)。土壤微生物碳源代谢特征在处理的第21天达到稳定状态,而土壤理化性质和土壤微生物群落结构在处理的第72天发生显著变化,同时研究发现淹水条件升高了土壤pH和铵态氮含量,降低了微生物群落多样性。由此可知,水分条件不仅会影响湿地土壤微生物总体碳源代谢活性强度,还会改变对不同碳源的相对利用能力,最终导致土壤环境发生改变。In order to understand the changes in metabolic characteristics of wetland soil microbial community under different water status, soil was collected from Poyang Lake wetland and was used for a 132 d greenhouse experiment, and Biolog was used to understand metabolic activity of soil microbial carbon source under three water conditions （drought, wetting and flooding）. The results showed that soil microbial metabolic activity was the highest in wetting condition, the average well color development （AWCD） was 1.34 and 3.95 times （120 h） of those in drought and flooding conditions on the 72＂d days, respectively. Meanwhile, the abilities of soil microbial utilizing different type carbon sources also were significantly changed under different treatments, polymers and carbohydrates were mainly used under drought condition （39.25% and 36.53%, respectively）, while amino acids mainly used （36.33%） under flooding condition. Metabolic characteristics of soil microbial carbon source reached a stable state on the 21st day, while soil physiochemical properties and soil microbial community structure were changed significantly on the 72no day. At the same time, it was found that soil pH and ammonium nitrogen content were increased and microbial community diversity was decreased under flooding condition. The results suggest that water status not only affects metabolic activity of total carbon source, but also changes the relative utilization ability of different carbon sources, and then changes soil environment in wetland soil.

关 键 词：湿地 土壤微生物 水分条件 碳源利用 功能多样性 

分 类 号：S154.36[农业科学—土壤学]