摘要
源头溪流作为连接陆地与内陆河流的关键节点以及海-陆碳库交互的先锋界面,其水-气界面CO_(2)排放对全球碳循环具有重要贡献。梳理源头溪流CO_(2)的产排基本过程,明确其排放的时空特征及其主要影响因子有助于重新认识河流系统碳处理能力,是进一步明晰全球碳循环过程的重要内容。本研究探讨了源头溪流CO_(2)的基本来源及过程(内源产生,外源输入);从年际、季节、昼夜的多维时间尺度,以及全球、区域、流域、生境的多维空间尺度对溪流CO_(2)排放规律进行系统分析;进一步从气象因子、溪流结构特征、水文地貌因子、陆域环境因子和水体理化因子等方面总结了影响溪流CO_(2)排放通量时空变异格局的关键因素;同时,分析了当前溪流CO_(2)排放监测的主要方法及其适应条件,为溪流CO_(2)监测的精确性提供参考。本文构建了溪流与陆地的碳耦合过程理论框架,呼吁溪流CO_(2)排放在陆域碳平衡中具有不可忽视的贡献。最后,根据研究中存在的不足,提出未来的研究应着重关注以下几个方面:(1)不同地理环境下溪流CO_(2)排放动力学过程解析;(2)全球不同地区溪流CO_(2)排放高时空分辨率的监测和数据库完善;(3)源头溪流CO_(2)排放与陆域景观格局的关联性及影响因素;(4)气候变化背景下溪流CO_(2)排放的响应特征;(5)区域及全球尺度溪流CO_(2)排放总量的精确估算;(6)寻求更加普适、有效的监测研究方法等。
Headwater stream plays a vital role in connecting terrestrial ecosystems with inland rivers, and is also a foremost interface of linking the terrestrial carbon sink with oceanic one. With the intensely biogeochemical processes, headwater streams are important contributors to CO_(2) emission budget from global inland waters and therefore affecting global carbon cycling. Clarifying the production and emission processes of CO_(2) in headwater streams, and illuminating their spatiotemporal characteristics as well as main regulating factors will be beneficial to re-understand carbon processing ability for river systems. Here, we reviewed the primary sources and processes of CO_(2) in headwater streams, including in-stream production and external input. We systematically analyzed the spatial and temporal variations at different time scales(i.e., annual, seasonal, daily and diurnal) and spatial scales(i.e., global, regional, watershed, and habitat) of CO_(2) emission from headwater streams. We summarized that the meteorological factors, stream structure characteristics, hydro-geomorphological factors, land environmental factors, and in-water physical and chemical factors were key regulators of the spatiotemporal variations in CO_(2) emission from headwater streams. Meanwhile, we summarized current methods for CO_(2) fluxes monitoring in inland water, and analyzed their applicability and optimization in headwater streams. We constructed a theoretical framework integrating the headstream waters into the carbon budget of headwater catchments, and proposed that the contribution of CO_(2) emission from streams to the terrestrial carbon balance cannot be ignored. Finally, based on the disadvantages existing in current research, we proposed several important research fields of CO_(2) emission from headstream, including(1) the analysis of dynamic process of CO_(2) emission from streams with different geographical environments;(2) the accumulation of observation database for headwater CO_(2) emission with high spatiotemporal res
作者
王继龙
王晓锋
袁兴中
吴胜男
李航
WANG Ji-long;WANG Xiao-feng;YUAN Xing-zhong;WU Sheng-nan;LI Hang(Chongqing Key Laboratory of Wetland Science Research of the Upper Reaches of the Yangtze River,Chongqing 401331,China;Three Gorges Reservoir Area Earth Surface Ecological Processes of Chongqing Observation and Research Station,Chongqing 405400,China;School of Geography and Tourism,Chongqing Normal University,Chongqing 400047,China;Faculty of Architecture and Urban Planning,Chongqing University,Chongqing 400030,China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2022年第5期1001-1014,共14页
Chinese Journal of Ecology
基金
国家自然科学基金项目(41807321)
重庆市科委基础研究与前沿探索(cstc2018jcyjAX0672)
重庆市教委科学技术研究重点项目(KJZDK202000502)资助。
关键词
源头溪流
CO_(2)排放
时空变异
影响因子
监测方法
headwater stream
CO_(2)evasion
spatiotemporal variation
influencing factor
monitoring method
