Collaborative Research: Quantifying Feedbacks between Groundwater Decline, Wind Erosion, and Ecological Change in Desert Vegetation

该奖项将资助地下水、土壤和植被特性以及沙漠尘埃产生之间相互作用的分析。沙漠土壤的风蚀被认为会对生态系统造成不可逆转的变化，而被调动的颗粒物会严重降低空气质量。在全球的沙漠中，产生沙尘最多的地区的特点是低海拔洼地，在那里，可风侵蚀的物质已经并将继续以河流的方式沉积。通常从这些地区抽取浅层地下水供农业和市政使用。由于许多沙漠地区对水的需求迅速增加，因此越来越需要了解地下水管理可能如何影响粉尘的产生。理想情况下，可以获得指导地下水管理的信息，以促进土壤稳定。该项目将利用对植被、土壤条件和风速的测量，对过去20年来地下水波动较大的一系列地点进行风蚀模拟。模型结果将与使用放射性沉降同位素和捕尘器对近期土壤流失的直接测量结果进行比较。最后，土壤资源可用性（养分和土壤水分）的测量将用于了解地下水下降、土壤流失和可能促进土壤持续不稳定的生态系统变化之间的反馈过程。更广泛的影响：该项目将对我们理解水管理对沙漠尘埃和空气质量的作用产生广泛的影响。这项工作将形成学术机构和监管团体之间的合作，在拟议的研究区域，靠近毕晓普，加州。因约县水务局和大盆地统一空气污染控制区将为该项目提供必要的数据，并获得关于如何调整其植被和空气质量管理活动以获得长期可持续性的重要信息。

This award will fund an analysis of the interactions between groundwater, soil and vegetation properties, and desert dust generation. Wind erosion of desert soils is thought to cause irreversible change to ecosystems, and the mobilized particulate matter can seriously degrade air quality. In deserts globally, regions that produce the most dust are characterized by low elevation depressions where wind erodible material has been and continues to be deposited fluvially. Shallow groundwater is often pumped from these regions for agricultural and municipal use. Since water demands are rapidly increasingly in many desert regions, there is increasing need to understand of how groundwater management might influence dust generation. Ideally, information could be attained that would guide groundwater management with the goal of promoting soil stability. This project will utilize measurements of vegetation and soil conditions and wind velocities to model wind erosion at a range of sites that experienced successively greater groundwater fluctuation over the past 20 years. Model results will be compared to direct measurements of recent soil loss using radiogenic fallout isotopes and dust traps. Finally, measurements of soil resource availability (nutrients and soil moisture) will be used to understand feedback processes between groundwater decline, soil loss, and ecosystem changes that might promote continued soil instability. Broader Impacts: The project will have a broad impact on our understanding of the role water management has on dust and air quality in deserts. The work will form collaborations between academic institutions and regulatory groups in the proposed study region, near Bishop, California. Both the Inyo County Water Department and the Great Basin Unified Air Pollution Control District will provide necessary data to the project and gain important information on how their vegetation and air quality management activities could be tailored to gain long-term sustainability.