Large Area DEM Generation Using Airborne LiDAR Data and Quality Control

摘要

Digital Elevation Model (DEM) is a crucial component in terrain-related applications.Researches on terrain data collection and DEM generation have received great attention.Traditional methods such as field surveying and photogrammetry can yield high accuracy terrain data,but they are time consuming and labour intensive,especially for large area.Airborne Light Detection and Ranging (LiDAR) -also referred to as Airborne Laser Scanning (ALS),provides an alternative for high density and high accuracy three dimensional terrain point data acquisition.LiDAR data have become a major source of digital terrain information and has been used in a wide of areas,with terrain modeling being the primary focus of most LiDAR collection missions.The use of LiDAR for terrain data collection and DEM generation is the most effective way and is becoming a standard practice in spatial science community.Although LiDAR data has become more affordable for users due to the gradually dropping of the costs of LiDAR data collection,how to effectively process the raw LiDAR data and extract useful information remains a big challenge.This paper presented ways to generate a high quality DEM in a large catchment area using LiDAR data.A number of research challenges such as terrain modeling methods,interpolation algorithms,DEM resolution,and data reduction were identified and discussed in detail for quality control ofa LiDAR-derived DEM.