Enhancing Flood Resilience: Geomorphological Insights into Lowland Riverscapes for Nature-Based Solutions

Aimed at achieving environmentally and economically smart growth in lowland riverscapes in the face of exacerbating flood threats, the elements of natural riverscapes, such as floodplain landforms, riparian forests, and wetlands can provide solutions to flood risk reduction. Geomorphological knowledge is crucial to working effectively with river processes and landforms in addressing flood hazards. In addition to unique landforms and habitats that can support flood mitigation, landscape-level geomorphological characteristics, such as geomorphological heterogeneity and connectivity, can also impact the attenuation and retention of downstream fluxes of water, sediment, and other materials, and thus resistance and resilience to floods. In this study, we employ a geomorphological approach to delineate the natural elements of lowland riverscapes as geomorphological habitats to assess their susceptibility to floods and erosion/sedimentation as well as their capacity to alleviate the negative impacts of floods. To delineate geomorphological habitats, we utilize a range of classification approaches and geospatial data including LiDAR-derived digital terrain models, airborne and satellite images, raster/vector data on vegetation, soils, and land-cover land-use. We then quantify the diversity, heterogeneity, and connectivity of delineated habitats using landscape ecological approaches and in the context of flood impacts and mitigation. Our geomorphological approach to riverscape characterization provides new insights on fundamental knowledge of natural elements as geomorphological habitats and their interconnections and interdependencies. This new knowledge has a high potential for developing geomorphologically derived nature-based solutions to flood management and enhancing flood resilience of lowland riverscapes.