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

Ohio State University, The, Columbus OH

Investigators

Abstract

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.