Diverse regional drivers of aquatic greenhouse gas emission - management and climate drivers

由于淡水系统中广泛的碳和氮循环，淡水是向大气排放天然温室气体的主要来源。排放量的大小可以通过人为的压力源显着改变，但我们对驱动排放的不同淡水系统的特性的机械理解是预测的主要差距。草原地区的内陆浅沃茨尤其如此，这是典型的干湿循环，管理湿地和池塘的蓄水，并管理许多河流的流量。温室气体预算预计将是高度动态的，气候和土地使用的变化预计将放大这一点。除此之外，还出现了对水质恶化、代价高昂的洪水和重要栖息地丧失的担忧，这些担忧正在推动政策的变化，并重新努力保护湿地和水资源管理。迫切需要详细审议政策和做法的变化对这些生态系统温室气体平衡的影响。我的计划将侧重于识别草原地区浅层沃茨温室气体排放的关键驱动因素。我将使用新的方法，包括我的研究团队开发的新传感器，来了解温室气体的释放速率。这将使我们了解不同释放途径对温室气体预算的重要性。我将使用当地景观的方法来连接草原湿地水生温室气体的条件，包括水文和化学的驱动程序。这将有助于深入了解区域温室气体排放如何响应自然周期和干扰而发生变化。在新的工作表明水库水位管理可以改变温室气体排放的基础上，我将确定人类水位管理对管理的草原河流温室气体排放的影响-包括受流量管理影响的大型河流发电，以及一条以污水为主的小型河流，日常用水模式决定流量模式。这项研究将奠定基础，帮助我们了解草原水生生态系统的当前排放量，并在温室气体排放的整个农场核算中考虑这些系统。这将有助于我们预测未来的变化，并限制对多年期区域水-大气温室气体交换的估计，确定气候，土地和水管理的影响。

Freshwaters are a key source of natural greenhouse gas emissions to the atmosphere, owing to widespread carbon and nitrogen cycling in these systems. The magnitude of emissions can be dramatically altered by anthropogenic stressors, but our mechanistic understanding of the properties of different freshwater systems that drive emissions is a major gap for prediction. This is especially true of shallow inland waters of the prairie region, which is typified by wet-dry cycles that govern water storage in wetlands and ponds, and managed flows in many rivers. Greenhouse gas budgets are expected to be highly dynamic, and changes in climate and land use are expected to amplify this. Overlaid on this are emerging concerns regarding degraded water quality, costly flooding, and the loss of important habitat that are driving changes in policy and renewed efforts at wetland conservation and water resource management. Detailed consideration of the effects of changes in policy and practice on the greenhouse gas balance of these ecosystems is urgently required.******My program will focus on identification of the key drivers of greenhouse gas emissions from shallow surface waters in the prairie region. I will use novel approaches, including new sensors developed by my research team, to understand rates of greenhouse gas release. This will allow us to understand the importance of different release pathways for greenhouse gas budgets. I will use a local landscape approach to link prairie wetland aquatic greenhouse gas conditions to drivers including hydrology and chemistry. This will provide insight into how regional greenhouse gas emissions shift in response to natural cycles, and disturbance. Building on new work demonstrating that water level management in reservoirs can alter greenhouse gas release, I will identify the effect of human water level management on greenhouse gas emissions in managed prairie rivers – including a large river impacted by flow management for electricity production, and a small sewage-dominated stream where daily water consumption patterns determine flow patterns. This research will build the foundation to help us understand current emissions from prairie aquatic ecosystems and to account for these systems in whole-farm accounting of greenhouse gas emissions. This will help us anticipate future change, and constrain estimates of regional water-atmosphere greenhouse gas exchange over multi-year periods, identifying influences of climate, land and water management.