Doctoral Dissertation Research: Assessing Variability in High Elevation Soil Moisture: Integrating Unmanned Aerial Vehicles, Satellites, and Field Hydrology

区域水文学尚未研究的一个方面是土壤水分在季节性蓄水中的作用，以及它与相关的气候、水文地质和环境动力学的关系。土壤水分储存可对关键牧场的供水和初级生产起到控制作用，特别是在旱季。因此，土壤水分的可变性对下游利益攸关方的水、粮食和生计安全具有隐含的作用。本论文将通过多光谱无人机(UAVs)、卫星遥感和野外水文学的有机结合，研究土壤水分多尺度时空变异的模式、过程和驱动因素。这项研究将在无人机可用于地球科学和相对难以进入的(例如高山)研究方面提供方法和技术进步的科学贡献，以及关于所研究系统的区域水文学的经验知识。这项研究的结果将有助于回答有关高山系统的水平衡以及对周期性或其他气候和人为力量的反应的基本问题。对绘制地图和了解地球表面的新方法感兴趣的科学家将会对无人机应用中的方法和技术进步感兴趣。这项研究的经验性见解将对研究未来水文情景以及山区过程和规模问题的科学家们感兴趣。这项研究侧重于水的可获得性，对长期的水文、能源和经济管理和规划具有重大影响。这项工作发生在热带秘鲁安第斯山脉的Cordillera Blanca山脉，这是一个对了解动态土壤水分过程和条件具有重要科学意义的地区。据推测，土壤水分是连接冰川融化、大气通量和土地覆盖的一个重要但不均匀的地下水水库。为了研究这些过程，该项目将陆地卫星图像和高分辨率(厘米)多光谱无人机图像与气候和水文数据相结合，以量化土壤含水率(SMC)的年际和季节变化。为了确定多尺度SMC时空变异的潜在驱动因素，本研究考察了高寒草甸和湿地SMC、地下水储量、降水、冰川退缩、蒸散和气候之间的水文地质联系。系统的知识将有助于许多高海拔山脉系统以及依赖它们的社会和经济系统。最后，这项工作将开发一种方法，通过该方法，可以使用无人机平台以高空间分辨率连续覆盖偏远环境中的SMC。

An unstudied aspect of regional hydrology is the role of soil moisture in seasonal water storage, and how it is related to associated climatic, hydrogeologic and environmental dynamics. Soil moisture storage may act as a control on both water provision and primary production of key grazing lands, especially during the dry season. Variability in soil moisture therefore has an implicit role in water, food and livelihood security for downstream stakeholders. This dissertation project will investigate the patterns, processes and drivers of multi-scale temporal and spatial variability in soil moisture content (SMC) through a novel integration of multispectral Unmanned Aerial Vehicles (UAVs), satellite remote sensing and field hydrology. This research will provide a scientific contribution of both methodological and technological advances in the ways that UAVs can be used in earth science and relatively inaccessible (e.g., high mountain) research as well as empirical knowledge regarding the regional hydrology of the systems under study. The findings of this research will help answer fundamental questions about the water balance of high mountain systems and responses to periodic or other climatic and anthropogenic forces. The methodological and technical advances in UAV applications will be of interest to scientists interested in new ways of mapping and understanding the earth surface. Empirical insights of this research will be of interest to scientists investigating future hydrologic scenarios as well as questions of process and scale in mountain regions. Through its focus on water availability this research has significant implications for and long-term hydrologic, energy, and economic management and planning. This work takes place in the Cordillera Blanca range of the tropical Peruvian Andes, an area of documented scientific importance in understanding dynamic soil moisture processes and conditions. It is hypothesized that soil moisture constitutes an important yet heterogeneous reservoir of groundwater that couples glacier melt, atmospheric fluxes and land cover. To investigate these processes, this project combines the analysis of Landsat satellite imagery and high resolution (centimeter) multispectral UAV imagery with climate and hydrology data to quantify inter-annual and seasonal variability in soil moisture content (SMC). To identify potential drivers of multi-scale spatial and temporal SMC variability, this research examines the hydrogeoecological connections among SMC, groundwater storage, precipitation, glacier recession, evapotranspiration and climate in the high alpine meadows and wetlands. The systematic knowledge will contribute to many high elevation mountain systems as well as the social and economic systems dependent upon them. Lastly, this work will develop a methodology through which SMC in remote environments can be rapidly quantified with continuous coverage at a high spatial resolution using a UAV platform.