Surface and Subsurface Hydrodynamics of Inland Wetlands in Brazil: Integrating High-Resolution Remote Sensing and Hydrogeophysics

Abstract. Inland wetlands, especially those isolated from surface water systems, present complex hydrological dynamics due to interactions between meteoric water, soil moisture, and groundwater. These ecosystems act as critical zones of recharge and discharge within a catchment, and their balance is increasingly disturbed by land use changes and climate variability. The challenge is even greater in isolated wetlands, where the absence of visible surface connectivity complicates the understanding of their hydrological role— particularly in regions subjected to seasonal heavy rainfall and high evapotranspiration. To overcome these challenges, this study applies an integration of high-resolution remote sensing and hydrogeophysical techniques to develop 3D surface and subsurface hydrological models. These tools allow detailed spatial analysis of terrain morphology, soil saturation zones, and subsurface water pathways, thereby enhancing the characterization of wetland structure and function. The surface modelling component utilizes drone imagery to delineate microtopography and surface flow patterns, while subsurface modelling incorporates geophysical surveys (electrical resistivity tomography) to map below-ground water distribution and interactions with soil and aquifers. This multidisciplinary approach offers insights into the water storage capacity and connectivity of wetlands, contributing to a more robust understanding of their ecological and hydrological significance.