Lakes are carbon dioxide(CO_(2))and methane(CH_(4))emission hotspots,whose associated flux is spatially vari-able.Many studies have investigated the impact of microorganisms and environmental factors on CO_(2) and CH_...Lakes are carbon dioxide(CO_(2))and methane(CH_(4))emission hotspots,whose associated flux is spatially vari-able.Many studies have investigated the impact of microorganisms and environmental factors on CO_(2) and CH_(4) emissions between different lakes.However,the carbon emissions and their influencing factors of different areas within a single lake remain poorly understood.Accordingly,this study investigates CO_(2) and CH_(4) emission hetero-geneity in a large floodplain lake system and distribution characteristics of associated functional microorganisms.Findings show that mean CO_(2) and CH_(4) flux values in the sub lake area were 62.03±24.21 mg/(m2·day)and 5.97±3.2μg/(m2·day),which were greater by factors of 1.78 and 2.96 compared to the water channel and the main lake area,respectively.The alpha diversity of methanogens in the sub lake area was lower than that in the main lake and water channel areas.The abundance of methanogens in bottom water layer was higher compared with the middle and surface layers.Conversely,the abundance of methane(CH_(4))-oxidizing bacteria in the surface layer was higher than that in the bottom layer.Additionally,the composition of methanogen and CH_(4)-oxidizing bacterial community,chlorophyll a(Chl-a),pH,total phosphorus(TP)and dissolved organic carbon(DOC)con-tent constituted the dominate driving factors affecting lake C emissions.Results from this study can be used to improve our understanding of lake spatial heterogeneous of CO_(2) and CH_(4) emission and the driving mechanisms within floodplain lakes under the coupling effects of functional C microorganisms and environmental factors.展开更多
三峡工程作为全球巨型水利枢纽之一,其水文泥沙问题对防洪安全、库容保持及流域生态健康具有深远影响。本研究基于文献计量法,利用CiteSpace对2010-2022年Web of Science(WOS)与中国知网(CNKI)的中英文文献进行定量分析,系统梳理三峡水...三峡工程作为全球巨型水利枢纽之一,其水文泥沙问题对防洪安全、库容保持及流域生态健康具有深远影响。本研究基于文献计量法,利用CiteSpace对2010-2022年Web of Science(WOS)与中国知网(CNKI)的中英文文献进行定量分析,系统梳理三峡水文泥沙研究脉络与热点演进。研究发现,国内外年均发文量超过310篇,研究热度持续攀升,国内研究主要聚焦库区泥沙淤积与调度优化,国际研究则侧重生态效应与风险评估。研究机构以长江水利委员会、武汉大学及中科院等机构为主要研究力量,但跨学科协作网络有待加强。入库水沙变化、库区淤积规律、坝下游冲刷效应、江湖关系演变、生态影响及监测技术6个关键问题的研究呈现阶段性深化特征,其中前5类问题以三峡工程整体竣工验收为节点分为两阶段,研究内容逐渐从现象观测转向机理探究,研究不断深入细化。泥沙监测技术研究自2020年起开始向智能化转型。本研究为三峡工程泥沙管理优化及全球巨型水库水沙调控提供了政策建议与理论参考。展开更多
基金supported by the National Natural Science Foundation of China(No.42225103).
文摘Lakes are carbon dioxide(CO_(2))and methane(CH_(4))emission hotspots,whose associated flux is spatially vari-able.Many studies have investigated the impact of microorganisms and environmental factors on CO_(2) and CH_(4) emissions between different lakes.However,the carbon emissions and their influencing factors of different areas within a single lake remain poorly understood.Accordingly,this study investigates CO_(2) and CH_(4) emission hetero-geneity in a large floodplain lake system and distribution characteristics of associated functional microorganisms.Findings show that mean CO_(2) and CH_(4) flux values in the sub lake area were 62.03±24.21 mg/(m2·day)and 5.97±3.2μg/(m2·day),which were greater by factors of 1.78 and 2.96 compared to the water channel and the main lake area,respectively.The alpha diversity of methanogens in the sub lake area was lower than that in the main lake and water channel areas.The abundance of methanogens in bottom water layer was higher compared with the middle and surface layers.Conversely,the abundance of methane(CH_(4))-oxidizing bacteria in the surface layer was higher than that in the bottom layer.Additionally,the composition of methanogen and CH_(4)-oxidizing bacterial community,chlorophyll a(Chl-a),pH,total phosphorus(TP)and dissolved organic carbon(DOC)con-tent constituted the dominate driving factors affecting lake C emissions.Results from this study can be used to improve our understanding of lake spatial heterogeneous of CO_(2) and CH_(4) emission and the driving mechanisms within floodplain lakes under the coupling effects of functional C microorganisms and environmental factors.
文摘三峡工程作为全球巨型水利枢纽之一,其水文泥沙问题对防洪安全、库容保持及流域生态健康具有深远影响。本研究基于文献计量法,利用CiteSpace对2010-2022年Web of Science(WOS)与中国知网(CNKI)的中英文文献进行定量分析,系统梳理三峡水文泥沙研究脉络与热点演进。研究发现,国内外年均发文量超过310篇,研究热度持续攀升,国内研究主要聚焦库区泥沙淤积与调度优化,国际研究则侧重生态效应与风险评估。研究机构以长江水利委员会、武汉大学及中科院等机构为主要研究力量,但跨学科协作网络有待加强。入库水沙变化、库区淤积规律、坝下游冲刷效应、江湖关系演变、生态影响及监测技术6个关键问题的研究呈现阶段性深化特征,其中前5类问题以三峡工程整体竣工验收为节点分为两阶段,研究内容逐渐从现象观测转向机理探究,研究不断深入细化。泥沙监测技术研究自2020年起开始向智能化转型。本研究为三峡工程泥沙管理优化及全球巨型水库水沙调控提供了政策建议与理论参考。
