Application of lidar technology for rivers analysis

Abstract

The availability of high resolution topographic data is strategic for quantitative and qualitative analysis of river environment. The topographic data derived by traditional regional cartography are often too coarse for detailed recognition and mapping of surface morphologic features, while the more accurate data derived by GPS or theodolite are expensive and time-consuming. The airborne laser altimetry technology (LiDAR, Light Detection And Ranging) provides high-resolution topographic data over large areas with high vertical and horizontal accuracy, thus can significantly contribute to a better representation of land surface. A valuable characteristic of this technology, which marks advantages over the traditional topographic survey techniques, is the capability to derive a high-reso- lution (~ 1 m) Digital Terrain Model (DTM) from the bare ground LiDAR data, by filtering vegetation and man-made features points (buildings, bridges) from raw data. The complex morphology, the wide range of land cover categories, and the presence of deep water bodies, make the airborne LiDAR application in river environments more complicated than application in different contexts. The aim of this work is to highlight the capabilities but also the limitations of airborne LiDAR in river studies, presenting some relevant researches and the main methodological aspects of this technology in fluvial environment.