藻源性有机质沉降对沉积物甲烷释放促进作用  

Enhancement and mechanism of algal-derived organic matter deposition on lake sediment methane release

作　　者：张楠 何凯 钟继承[2] 安燕飞[3] 袁和忠[1] 张雷[2] ZHANG Nan;HE Kai;ZHONG Ji-cheng;AN Yan-fei;YUAN He-zhong;ZHANG Lei(School of Environmental Science and Engineering,Nanjing University of Information Science&Technology,Nanjing 210044,China;State Key Laboratory of Lake Science and Environment,Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences,Nanjing 210008,China;School of Resources and Environmental Engineering,Anhui University,Hefei 230601,China)

机构地区：[1]南京信息工程大学环境科学与工程学院,江苏南京210044 [2]中国科学院南京地理与湖泊研究所,湖泊与环境国家重点实验室,江苏南京210008 [3]安徽大学资源与环境工程学院,安徽合肥230601

出　　处：《中国环境科学》2023年第12期6641-6650,共10页China Environmental Science

基　　金：国家自然科学基金资助项目(42177228,41771122);自然资源部国土(耕地)生态监测与修复工程技术创新中心开放课题(GTST2021-007)。

摘　　要：采集巢湖西北湖湾区水与沉积物样品,模拟藻源性有机质沉降对CH4释放的驱动作用.培养结果显示,加藻组CH4释放通量(1.59±0.51)^(98.89±14.30)μmol/(m^(2)·h)显著高于对照组(0.02±0.016)^(1.37±0.44)μmol/(m^(2)·h)(P<0.001).培养过程中,藻源性有机质降解迅速,提供了大量产甲烷底物,溶解氧和硫酸根等电子受体减少,创造了有利产甲烷菌的环境,增加了产甲烷菌数量,尤其是乙酸营养型产甲烷菌.综上,藻源性有机质的大量输入,可以增大沉积物产甲烷速率和甲烷释放通量,其中乙酸营养型产甲烷菌起到重要作用.Lakes are important natural sources of methane(CH4)release.A well-known view is that frequent cyanobacterial blooms promote CH4 release in freshwater lakes,but the specific driving process and mechanism are still unclear.In this study,the driving process and effect of algal-derived organic matter deposition on CH4 release were simulated and studied by using water and sediment samples from Lake Chaohu.The results showed that the CH4 release flux in the group with the treatment of additional added algae was(1.59±0.51)~(98.89±14.30)μmol/(m^(2)·h))significantly higher than that in the control group(0.02±0.016)~(1.37±0.44)μmol/(m^(2)·h))(P<0.001).During the simulating experiment,the degradation of algal-derived organic matter provided a large number of substrates for methane production while the reduction of electron acceptors such as dissolved oxygen and sulfate created an environment conducive to methanogens,which resulted in a massive proliferation of methanogens,especially acetic acid trophic methanogens.Our study clearly demonstrated that the large input of algal-derived organic matter increased the methane production rate and methane release flux of lake sediments with acetic acid trophic methanogens playing an important role.

关 键 词：释放通量 产甲烷菌 温室气体 二氧化碳 湖泊 水华 

分 类 号：X511[环境科学与工程—环境工程]