Investigating Fluvial Ecosystem Structure and Change on the Landscape Scale Using Topobathymetric Lidar

Rivers and streams are highly dynamic components of landscapes and their expressed geomorphology creates a foundation for the structure of highly active ecosystem zones.  Flood and landslide hazards typically develop adjacent to fluvial corridors that integrate and capture the response to past and present sediment and water supplies across broad regions. Riverine aquatic biodiversity is diminishing dramatically across landscapes. Due to cost and logistical constraints investigation and mitigation of these trends was previously limited to fragmented, small scale local studies. Understanding and conserving entire fluvial ecosystems requires knowledge of processes in streams, analysis of the interactions between channels, and extrapolation to the functions of hydrologic networks. Terrestrial–aquatic lidar now enables regional capture of continuous three-dimensional channel and floodplain topography. This recent advance in remote sensing has great potential to spawn landscape-scale studies and conservation of broadly networked aquatic ecosystems. These new inland topobathymetric mapping lidars are typically full temporal waveform resolving, green-wavelength laser, low beam divergence airborne instruments that seamlessly integrate the spatially detailed capture of channel morphology, adjacent river banks and floodplains, and riparian vegetation structure.