Greenhouse gas emissions from rivers and streams along a steep gradient of biogeochemical constituents and land use

沿生物地球化学成分和土地利用陡峭梯度的河流和溪流的温室气体排放

• 批准号: 242560981
• 负责人: Professor Dr. Andreas Lorke
• 金额: --
• 依托单位: Department of Earth and Environmental Sciences (E&ES)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/242560981?language=en
• 关键词: Greenhouse; gas; emissions; rivers; streams

Inland waters play a vital role in regional to global carbon cycling. Among the latest and least understood aspects in this context is the amount of carbon emitted from inland waters into the atmosphere as carbon dioxide (CO2) and as methane (CH4). Recent estimates suggest that less than half of the carbon that enters freshwater ecosystems from the terrestrial biome ultimately reaches the ocean. The remaining amount of terrestrial carbon, which is processed and eventually emitted into the atmosphere from inland waters, is a significant, though often neglected component of carbon cycling and greenhouse gas (GHG) budgets. While recent research effort focused mainly on lakes and reservoirs as GHG sources, major research gaps exist in respect to emissions from small streams and headwater systems, as well as in respect to the contribution of CH4 to the total GHG potential of emitted gases. The objectives of the proposed project are twofold: Our major goal is a quantitative assessment of the key processes controlling the intensity and flux paths of CO2 and CH4 emission from the fluvial network of a complete watershed. This process-based assessment will be obtained from extensive measurements within the core study area, the fluvial network of the 271 km2 watershed of the River Queich. This area consists of streams originating within the biosphere reserve Pfälzerwald and flowing through a contrasting landscape in terms of land use within less than 100 km distance. The measurements include GHG partial pressures in stream water, gas exchange velocity, bubble- and plant-mediated gas fluxes, stream metabolism, and surface area. A geographic information system will be used for up-scaling of the reach-scale measurements to the entire study area. As a second objective of this proposal, we will analyze the accuracy of this up-scaling, and there with the accuracy of regional-scale estimates of GHG fluxes and its dependence on quality and quantity of underlying data. These finding will be applied to estimate GHG emissions from an extended study area, where only low-level sampling will be performed. We expect land use and stream structural quality to be among major determinants for the key processes controlling local fluxes and for the magnitude of regional-scale emissions rates. Our measurement program and proposed analyses allows for a quantitative assessment of the impacts of anthropogenic activities on carbon processing and corresponding GHG emission from streams. Thus, this project may serve as a reference study for assessing GHG emissions from anthropogenically altered fluvial networks.

内陆沃茨在区域乃至全球碳循环中发挥着至关重要的作用。在这方面，最新和最不为人所知的方面是内陆沃茨以二氧化碳（CO2）和甲烷（CH4）形式排放到大气中的碳量。最近的估计表明，从陆地生物群落进入淡水生态系统的碳中，只有不到一半最终到达海洋。陆地碳的剩余量经过处理并最终从内陆沃茨排放到大气中，是碳循环和温室气体预算的一个重要组成部分，尽管常常被忽视。虽然最近的研究工作主要集中在作为温室气体源的湖泊和水库上，但在小溪流和源头系统的排放量方面，以及在甲烷对排放气体的温室气体总潜力的贡献方面，存在着重大的研究空白。拟议项目的目标是双重的：我们的主要目标是一个定量评估的关键过程控制的强度和通量路径的CO2和CH4排放从河流网络的一个完整的流域。这种基于过程的评估将获得广泛的测量范围内的核心研究领域，河流网络的271平方公里的流域的奎克河。这一地区由发源于普费尔策瓦尔德生物圈保护区内的溪流组成，在不到100公里的距离内流经土地利用方面形成鲜明对比的景观。测量包括温室气体分压在流水，气体交换速度，气泡和植物介导的气体通量，流代谢，和表面积。将利用地理信息系统将可达尺度测量扩大到整个研究区域。作为本提案的第二个目标，我们将分析这种放大的准确性，并与区域尺度的温室气体通量估计的准确性及其对基础数据的质量和数量的依赖。这些发现将被应用于估计温室气体排放量从一个扩展的研究领域，只有低水平的采样将进行。我们预计，土地利用和流结构质量的主要决定因素控制当地通量的关键过程和区域尺度的排放率的大小。我们的测量程序和建议的分析允许定量评估人类活动对碳处理和相应的温室气体排放流的影响。因此，该项目可作为评估温室气体排放量的参考研究，从气候变化的河流网络。

项目成果

Regional-scale lateral carbon transport and CO 2 evasion in temperate stream catchments

• DOI: 10.5194/bg-14-5003-2017
• 发表时间: 2017-11
• 期刊: Biogeosciences
• 影响因子: 4.9
• 作者: Katrin Magin;Celia Somlai-Haase;R. Schäfer;A. Lorke

Sediment Properties Drive Spatial Variability of Potential Methane Production and Oxidation in Small Streams

• DOI: 10.1029/2019jg005213
• 发表时间: 2020-01-01
• 期刊: JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
• 影响因子: 3.7
• 作者: Bodmer, P.;Wilkinson, J.;Lorke, A.
• 通讯作者: Lorke, A.

Deconstructing Methane Emissions from a Small Northern European River: Hydrodynamics and Temperature as Key Drivers.

• DOI: 10.1021/acs.est.6b03268
• 发表时间: 2016-10
• 期刊: Environmental science & technology
• 影响因子: 11.4
• 作者: D. McGinnis;N. Bilsley;M. Schmidt;P. Fietzek;P. Bodmer;K. Premke;A. Lorke;S. Flury