小微黑臭水体修复过程中温室气体排放特征  

Greenhouse gases emissions in high polluted water and its restoration

作　　者：陈成[1] 杨正健[1,2] 王从锋 郭小娟 唐金云 CHEN Cheng;YANG Zheng-jian;WANG Cong-feng;GUO Xiao-juan;TANG Jin-yun(China Three Gorges University,Hubei Field Observation and Scientific Research Station for Water Ecosystem in Three Gorges Reservoirs,Yichang 443002,China;Hubei University of Technology,Hubei Key Laboratory of Ecological Restoration of River-lakes and Algal Utilization,Wuhan 430068,China)

机构地区：[1]三峡大学,三峡水库生态系统湖北省野外科学观测研究站,湖北宜昌443002 [2]湖北工业大学,河湖生态修复与藻类利用湖北省重点实验室,湖北武汉430068

出　　处：《中国环境科学》2023年第8期4211-4218,共8页China Environmental Science

基　　金：国家自然科学基金资助项目(52079075,U2040220,52079074);湖北省杰出青年基金资助项目(2021CFA097)。

摘　　要：为分析小微黑臭水体修复过程中温室气体释放规律,选择典型小微黑臭水体分别设置污染拦截并生态修复(W1)、污染拦截(W2)和污染直排(W3)3组围隔进行对比实验研究.结果表明,在实验期内,污染拦截并生态修复围隔中CO_(2)、CH_(4)和N_(2)O扩散通量分别为(5671.9±1189.5)、(39.2±10.1)和(4.2±2.2)μmol/(m^(2)·h),其CO_(2)当量贡献率分别为76.51%、6.54%和16.95%;仅污染拦截围隔中CO_(2)、CH_(4)和N_(2)O扩散通量分别为(1139.3±1169.6)、(102.1±35.6)和(20.0±14.1)μmol/(m^(2)·h),其CO_(2)当量贡献率分别为13.64%、15.12%和71.24%;污染直排围隔中CO_(2)、CH_(4)和N_(2)O扩散通量分别为(9140.3±256.4)、(1126.8±215.1)和(1.8±1.7)μmol/(m^(2)·h),其CO_(2)当量贡献率分别为38.74%、59.04%和2.22%.实验围隔中三大温室气体释放CO_(2)总当量大小表现为:污染直排>污染拦截>生态修复.污染直排围隔(W3)中缺氧且沉积物有机质含量较高,有机质降解过程中消耗大量O_(2)并释放CH_(4)和CO_(2),导致其释放通量及当量贡献率较高;污染拦截围隔(W2)发生了水体富营养化及藻类水华,藻类光合作用产氧消耗CO_(2)并释放N_(2)O,导致N_(2)O较高、CO_(2)较低,N_(2)O是其当量最主要贡献者;污染拦截并生态修复围隔(W1)中DO较高,抑制CH_(4)产生并加速氧化,同时抑制反硝化作用导致N_(2)O较低,减少了向大气的总温室气体排放.In order to analyze the greenhouse gases emissions in high polluted water,three experimental enclosures were set as:pollution intercepted and ecological restoration treated enclosure(W1),pollution intercepted enclosure(W2)and no treatment enclosure(W3).The CO_(2),CH_(4) and N_(2)O diffusion fluxes in W1 were(5671.9±1189.5)μmol/(m^(2)·h),(39.2±10.1)μmol/(m^(2)·h)and(4.2±2.2)μmol/(m^(2)·h),respectively,and contributed for 76.51%,6.54%and 16.95%of the total CO_(2) equivalent emission.In the pollution intercepted enclosure W2,the CO_(2),CH_(4) and N_(2)O diffusion fluxes were(1139.3±1169.6)μmol/(m^(2)·h),(102.1±35.6)μmol/(m^(2)·h)and(20.0±14.1)μmol/(m^(2)·h),and contributed for 13.64%,15.12% and 71.24% of the total CO_(2) equivalent emission.In no treatment enclosure W3,the CO_(2),CH_(4) and N_(2)O diffusion fluxes were(9140.3±256.4)μmol/(m^(2)·h),(1126.8±215.1)μmol/(m^(2)·h)and(1.8±1.7)μmol/(m^(2)·h),and contributed for 38.74%,59.04% and 2.22% of the total CO_(2) equivalent emission.The total greenhouse gases emission in the experimental enclosures sorted as:no treatment high polluted water>pollution intercepted enclosure>pollution intercepted and ecological restoration treated enclosure.Organic matter degradation in no treatment enclosure W3 resulted in anoxic and high CH_(4) and CO_(2) emission.In pollution intercepted enclosure W2,eutrophication and algal bloom occurred.Algae photosynthesis consumed CO_(2) and released N_(2)O,therefor N_(2)O was the main contributor(71.24%)to the total emission.The high DO in the pollution intercepted and ecological restoration enclosure(W1)inhibited the production of CH_(4) and accelerated its oxidation,and the inhibition of denitrification resulted in low N_(2)O,which reduced the total greenhouse gases emissions to the atmosphere.

关 键 词：小微黑臭水体 温室气体排放 CO_(2)、CH_(4)和N_(2)O当量贡献 生态修复 

分 类 号：X52[环境科学与工程—环境工程]