Laser scanning applications in fluvial studies
During recent decades, the use of high-resolution light detection and ranging altimetry (LiDAR) data in fluvial studies has rapidly increased. Airborne laser scanning (ALS) can be used to extensively map riverine topography. Although airborne blue/green LiDAR can also be utilized for the mapping of river bathymetry, the accuracy levels achieved are not as good as those of terrain elevation measurements. Moreover, airborne bathymetric LiDAR is not yet suitable for mapping shallow water areas. More detailed topographical data may be obtained by fixed-position terrestrial laser scanning (TLS) or mobile terrestrial laser scanning (MLS). One of the newest applications of MLS approaches involves a boat/cart-based mobile mapping system (BoMMS/CartMMS). This set-up includes laser scanning and imaging from a boat moving along a river course and may be used to expand the spatial extent of terrestrial scanning. Detailed digital terrain models (DTMs) derived from LiDAR data can be used to improve the recognition of fluvial landforms, the geometric data of hydraulic modelling, and the estimation of flood inundation extents and fluvial processes.