Greenhouse Gas Instrumentation System for Aquatic Ecosystems (GHG-Aqua)

土地利用和农业排放的温室气体约占人类温室气体排放总量的四分之一。虽然造成这些排放的一些活动，如砍伐森林，很容易观察到，但其他活动则不然。现在人们认识到，淡水生态系统是全球碳循环的活跃组成部分；河流和湖泊处理从集水区接收的有机物质和营养物质，向大气排放二氧化碳和甲烷，通过水生初级生产封存二氧化碳，并将碳埋在沉积物中。人类活动，如农业和城市废水造成的营养物质和有机物污染，排水网络的改造，以及从农场池塘到水电和供水水库等新水体的广泛创造，极大地改变了自然水生生物地球化学过程。在一些内陆水域，这导致大量温室气体排放到大气中。然而，这些排放在时间和空间上变化很大，通过一系列途径发生，因此在所需的时间和空间尺度上特别难以测量。技术的进步，包括高频监测系统、自动船载传感器和可在多个地点远程操作的新型低成本自动化系统，现在有可能捕获这些重要但鲜为人知的排放。在温室气体-水项目中，我们将建立一个综合的，全英国范围的系统来测量水生温室气体排放，将高度仪器化的“哨兵”站点与部署在英国内陆水域的分布式，社区运行的低成本传感器系统网络相结合，以测量跨越人类干扰梯度的河流，湖泊，池塘，运河和水库的排放。一套流动仪器将能够基于运动详细评估通量和基本过程的垂直和空间变化。这一全球独特且高度集成的测量系统将改变我们量化内陆水域水生温室气体排放的能力。在大量研究人员的支持下，这将有助于使英国在该领域处于世界领先地位，并将促进未来的国内和国际科学研究，以了解自然和人工水体作为碳循环活跃区域的作用，以及温室气体的来源和汇。我们将与政府合作，将这些通量纳入英国的国家排放清单；与水务行业合作，支持其减缓气候变化的业务目标；并与从事保护和恢复淡水环境的慈善机构、机构和其他方面合作，确保能够通过有针对性的有效投资，捕捉、报告和维持其活动所产生的减缓气候变化的惠益。

Land-use and agriculture are responsible for around one quarter of all human greenhouse gas (GHG) emissions. While some of the activities that contribute to these emissions, such as deforestation, are readily observable, others are not. It is now recognised that freshwater ecosystems are active components of the global carbon cycle; rivers and lakes process the organic matter and nutrients they receive from their catchments, emit carbon dioxide (CO2) and methane to the atmosphere, sequester CO2 through aquatic primary production, and bury carbon in their sediments. Human activities such as nutrient and organic matter pollution from agriculture and urban wastewater, modification of drainage networks, and the widespread creation of new water bodies, from farm ponds to hydro-electric and water supply reservoirs, have greatly modified natural aquatic biogeochemical processes. In some inland waters, this has led to large GHG emissions to the atmosphere. However these emissions are highly variable in time and space, occur via a range of pathways, and are consequently exceptionally hard to measure on the temporal and spatial scales required. Advances in technology, including high-frequency monitoring systems, autonomous boat-mounted sensors and novel, low-cost automated systems that can be operated remotely across multiple locations, now offer the potential to capture these important but poorly understood emissions. In the GHG-Aqua project we will establish an integrated, UK-wide system for measuring aquatic GHG emissions, combining a core of highly instrumented 'Sentinel' sites with a distributed, community-run network of low-cost sensor systems deployed across UK inland waters to measure emissions from rivers, lakes, ponds, canals and reservoirs across gradients of human disturbance. A mobile instrument suite will enable detailed campaign-based assessment of vertical and spatial variations in fluxes and underlying processes. This globally unique and highly integrated measurement system will transform our capability to quantify aquatic GHG emissions from inland waters. With the support of a large community of researchers it will help to make the UK a world-leader in the field, and will facilitate future national and international scientific research to understand the role of natural and constructed waterbodies as active zones of carbon cycling, and sources and sinks for GHGs. We will work with government to include these fluxes in the UK's national emissions inventory; with the water industry to support their operational climate change mitigation targets; and with charities, agencies and others engaged in protecting and restoring freshwater environments to ensure that the climate change mitigation benefits of their activities can be captured, reported and sustained through effectively targeted investment.