Analysis of gully erosion hazard using high resolution terrestrial LiDAR

摘要

Gully erosion removes large volumes of soil and water from complex areas. It's difficult to quantify the loss of soil because the footprint of individual gullies is too complex to be captured by most common measures, such as general available digital elevation models (DEMs). LiDAR (Light Detection and Ranging) is a recent innovation technique widely used in topographic surveying, smart city, historic preservation, revere engineering, etc. Ground-based LiDAR has the potential to provide the required data with non-contacting, convenient, fast and high accuracy at lower cost. In this study, two different Terrestrial Laser scanners (TLS) were used to monitor an individual gully. Terrain complexity and volumetric estimates of the eroded sediment were produced by comparing the LiDAR-derived DEMs under different point cloud resolution. The result showed that the surface roughness and erosion sediment were increased with higher resolution point cloud. However, time-consuming and computational complexity was suddenly raised as dense point cloud provided more details information. This paper provides a new method for how to choose a moderate resolution in dealing with gully erosion in regional area.