湖泊科学2024，Vol.36Issue(1)：17-33,17.DOI:10.18307/2024.0102
三峡水库支流甲烷排放研究进展
Research progress on methane emissions from tributaries of the Three Gorges Reser-voir
摘要
Abstract
Methane(CH4)has a large contribution to the global greenhouse effect.The CH4 emission from the Three Gorges Res-ervoir has attracted considerable attention since its impoundment in 2003.However,the unique operation mode of the Three Gorges Reservoir affected the CH4 emission and transport in its tributaries.However,the underlying mechanism of CH4 emissions remains unclear.This study reviewed the research progress of CH4 emission from the tributaries of the Three Gorges Reservoir.The CH4 flu-xes of typical tributaries were generally higher than those of the main streams.The CH4 emission flux of some tail tributaries of the Three Gorges Reservoir was higher than that of the head and tributaries.The CH4 fluxes in most typical tributaries have peak values in summer,and relatively low values during high water operation in winter.The factors influencing CH4 emission from these tributa-ries mainly included algae,climatic factors,hydrodynamic conditions and human activities.The future research hotspots were sum-marized.1)Algae:The impoundment of the Three Gorges Reservoir has led to intensified algal blooms in some of its tributaries.The dominant species of phytoplankton gradually changed from river-type algae to lake-type algae in the early stage of water storage.This succession of phytoplankton would increase CH4 production.In addition,the algal bloom in tributaries of the Three Gorges Reservoir,would undergo seasonal succession.Phytoplankton dominated by green algae and cyanobacteria has high contribution to CH4 emission.2)Climatic factors;The generation and consumption rate of tributary CH4 were positively correlated with tempera-ture.In general,higher temperature promote the growth of algae.However,the out-of-season scheduling mode of the Three Gorges Reservoir also enhances phytoplankton production in winter.The tributary temperature stratification would further aggravate algal bloom,providing substrate for CH4 production.Rainfall affected CH4 discharge of these tributaries by increasing the content of or-ganic matter,the abundance of methanogenic bacteria,and disturbing the surface water.The degree of impact was related to the magnitude of rainfall runoff.3)Hydraulic conditions:During the low water level period of the Three Gorges Reservoir,CH4 con-sumption in the water body was lower enhancing CH4 transmission.Moreover,the water level change caused by the operation of the reservoir also affects environmental factors such as temperature stratification,algae growth and organic matter distribution,which has an indirect impact on the CH4 flux of tributaries.4)Human activities:Land use changes caused by human activities would in-crease nutrient concentrations in tributary water bodies and enhance nutrient-related metabolism of bacterial communities,resulting in an increase of CH4 emission.The damming and reservoir operation in the tributary area changed the hydrodynamic conditions of the tributary,blocked the transport of organic matter,and thus increased the total organic carbon content in the sediment,provi-ding more substrate for CH4 production.Finally,the future research hotspots were summarized to provide scientific basic for the management of CH4 emissions in the Three Gorges Reservoir.关键词
三峡水库/支流/甲烷排放/水环境条件/水动力条件/人类活动/气象条件Key words
Three Gorges Reservoir/tributaries/methane emission/water environmental conditions/hydrodynamic conditions/human activities/meteorological conditions引用本文复制引用
毛羽丰,何蕊序,李宏,杨胜发,余薇薇,叶开来,林彤,白小霞,何强..三峡水库支流甲烷排放研究进展[J].湖泊科学,2024,36(1):17-33,17.基金项目
国家自然科学基金项目(52270196,U20A20326,52000018)、重庆市自然科学基金项目(cstc2020jcyj-msxmX0176)、重庆市教育委员会科学技术项目(KJQN202000745)、中国科协青年人才托举工程项目(2022QNRC001)和水利水运工程教育部重点实验室开放基金项目(SLK2021B06)联合资助. （52270196,U20A20326,52000018）
