Study on the Application of Airborne LiDAR in Topographic Mapping of Reservoir Bank

金沙江下游水库具有地形陡峭、植被茂密等特点。针对库岸传统测量方式作业难度大、风险源多、效率低下；航空摄影测量受天气影响大、植被覆盖区域无法获取地面信息等难题，提出应用机载LiDAR获取库岸三维地形信息的方案。机载LiDAR具有非接触性测量、全天候作业、较强的植被穿透性等优点，可以很好解决以往库岸地形测绘方式的不足。通过检验点定量分析高程较差表明：总体中误差为±0.12 m，不同地物属性的中误差平均值为±0.12 m，点云精度满足相关测量规范要求，适用于金沙江下游大比例尺库岸地形测绘项目。The reservoir in the lower reaches of Jinsha River is characterized by steep terrain and dense vegetation. The traditional measurement method of reservoir bank is difficult to operate, and has many risk sources and low efficiency. Aerial photogrammetry suffers from weather impacts and inability to acquire ground information in areas with heavy vegetation cover. To address these issues, a proposal has been made to use airborne LiDAR for acquiring three-dimensional terrain information of the reservoir bank. Airborne LiDAR has the advantages of non-contact measurement, all-weather operation, strong vegetation penetration, etc., which can solve the shortcomings of the previous methods for topographic mapping of reservoir bank. Through the quantitative analysis of the elevation difference of the test points, it is shown that the overall median error is ±0.12 m, and the average median error of different ground features is ±0.12 m. The accuracy of the point cloud meets the requirements of the relevant measurement standards, and is suitable for the Large-scale topographic mapping project of the reservoir bank in the lower reaches of the Jinsha River.