摘要
以西南典型高原湖泊阳宗海为研究对象,于2020年11月应用新型快速水-气平衡装置(FaRAGE)及便携式温室气体分析仪,开展了表层水体和垂向剖面溶解CH_(4)浓度的高分辨率监测,揭示了溶解CH_(4)浓度空间分布特征及影响因素.结果表明,阳宗海表层水体溶解CH_(4)浓度为0.02~0.97μmol/L,表现为大气甲烷的源.空间上呈现出南北高、中部低的分布特征,与水生植物分布、入湖河流输出和水深等因素密切相关.湖泊不同区域垂向剖面溶解CH_(4)浓度分布较为一致,湖心区CH_(4)氧化消耗最为明显.自展分析表明,基于少量样点监测的CH_(4)排放估算具有较大不确定性,准确估算阳宗海CH_(4)扩散通量所需最小采样点数量约为3.7个/km^(2),高空间分辨率的监测对于湖库碳排放的准确估计十分必要.
Near-surface and vertical profiles of dissolved CH_(4) concentrations were measured at a high resolution using the new fast-response automated gas equilibrator(FaRAGE)connected to a greenhouse gas analyzer at Yangzonghai Lake in November 2020,to investigate the spatial pattern of dissolved CH_(4) and its driving factors.Results showed that dissolved CH_(4) concentrations of surface water ranged between 0.02 and 0.97μmol/L,indicating a net source of atmosphere CH_(4).The dissolved CH_(4) was relatively higher in the north and south parts of the lake,but lower in the middle area,which was mainly influenced by aquatic plants distribution,discharge from inflow rivers and topographical conditions.Vertical profiles of dissolved CH_(4) at different spots of the lake exhibited relatively consistent pattern,while CH_(4) was more significantly oxidized in the middle section.The bootstrap analysis suggested that estimates of CH_(4) emission derived from fewer measurements were subjected to potentially large biases,and the minimum number of sampling sites that guaranteed an accurate estimation of diffusive CH_(4) flux at Yangzonghai Lake was 3.7per km^(2).It was necessary to perform high-resolution observations of CH_(4) concentration for an accurate estimation of carbon emission from lakes or reservoirs.
作者
郑祥旺
陈敏
肖尚斌
王圣瑞
王雪竹
陈巍
刘佳
许浩霆
ZHENG Xiang-wang;CHEN Min;XIAO Shang-bin;WANG Sheng-rui;WANG Xue-zhu;CHEN Wei;LIU Jia;XU Hao-ting(Engineering Research Center of Eco-environment in Three Gorges Reservoir Region,Yichang 443002,China;College of Hydraulic and Environmental Engineering,China Three Gorges University,Yichang 443002,China;Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir,Yichang 443002,China;College of Water Sciences,Beijing Normal University,Beijing 100875,China;Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed,Kunming 650034,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2022年第2期834-842,共9页
China Environmental Science
基金
国家自然科学基金资助项目(41807513,51979148)
湖北省自然科学基金创新群体项目(2019CFA032)。
关键词
温室气体
溶解浓度
空间分布
通量
阳宗海
greenhouse gas
dissolved concentration
spatial distribution
flux
Yangzonghai Lake
