Collaborative Research: NSFGEO-NERC: Aeolian dust responses to regional ecosystem change

概述：拟议的研究将建立由三种干扰机制引起的北美区域生态系统变化的尘埃排放响应：1)大量离散的、小规模(&lt；10公顷)与能源(石油和天然气)开发相关的突然生态系统变化；2)离散、大规模(&gt；1000公顷)、与火有关的突然生态系统变化以及促进入侵草地和改变火风侵蚀制度的生态反馈；以及3)与持续灌木入侵沙漠草原相关的扩散、大范围(&gt；1000公顷)普遍的生态系统变化。将使用遥感和大范围标准化生态数据集驱动的新的扬尘模型来解决土壤和植被-风沙输送相互作用的力学问题。这些模型将使用国家风蚀研究网络观测站的数据进行校准，然后应用于探索研究地区的粉尘排放模式。将使用国家生态数据集来分析驱动因素，并解释不同干扰制度下区域生态系统变化的粉尘排放响应。知识价值：这项建议审查了区域生态系统变化(土地利用和土地复盖变化)对北美粉尘排放量的地貌机制和影响。来自北美沙漠的粉尘对人类健康和运输系统、水资源、农业生产及其对生物地球化学循环和气候的反馈影响深远，因此具有区域重要性。由于干旱、土地利用和管理压力以及气候变化，粉尘源区正在经历生态系统结构和功能的变化。地块尺度的研究探索了旱地植被变化和风沙过程之间的相互作用。然而，生态系统变化对当前和未来区域粉尘排放的重要性尚未在大范围内确定。这项研究将改变我们对人类土地利用压力和自然干扰导致的不同类型生态系统变化如何影响区域粉尘排放的理解。这些发现将极大地提高我们对沙尘循环和生态系统变化的人为驱动因素之间的耦合的理解。

Overview: The proposed research will establish dust emission responses to regional ecosystem change across North America due to three disturbance regimes: 1) numerous discrete, small scale (<10 ha), abrupt ecosystem changes associated with energy (oil and gas) development; 2) discrete, large scale (>1000 ha), abrupt ecosystem change associated with fire and ecological feedbacks that promote invasive grasses and altered fire-wind erosion regimes; and 3) diffuse, large scale (>1000 ha), pervasive ecosystem changes associated with sustained shrub invasion of desert grasslands. New dust emission models driven by remote-sensing and broad-scale standardized ecological datasets will be used to resolve the mechanics of soil and vegetation-aeolian transport interactions. The models will be calibrated using data from National Wind Erosion Research Network observatory sites, then applied to explore patterns of dust emission across the study regions. National ecological datasets will be used to analyze the drivers and interpret dust emission responses to regional ecosystem changes across the disturbance regimes. Intellectual Merit: This proposal examines the geomorphic mechanisms and impacts of regional ecosystem change (land use and land cover change) on the magnitude of North American dust emission. Dust originating from North American deserts is regionally important for its profound impacts on human health and transportation systems, water resources, agricultural production, and its feedbacks to biogeochemical cycling and climate. Dust source regions are experiencing changes in ecosystem structure and function due to drought, land use and management pressures, and climate change. Plot-scale research has explored the interactions between vegetation change and aeolian processes in drylands. However, the significance of ecosystem changes for current and future regional dust emissions has not been established over large areas. This research will transform our understanding of how different types of ecosystem change due to human land-use pressures and natural disturbances impact regional dust emissions. Findings will significantly improve our understanding of the coupling between the dust cycle and anthropogenic drivers of ecosystem change.