ACCURACY ASSESSMENT OF LIDAR BASED DTM AND GROUND SURVEY BASED DTM

Digital Terrain Models (DTMs) are widely used to model the elevation and topography of the ground surface; however, their accuracy largely depends on the data acquisition technique employed. This study focuses on the accuracy assessment of Ground Survey–Based DTM and LiDAR–based DTM to evaluate their reliability and suitability for topographic applications. Ground survey data were collected using Global Navigation Satellite System (GNSS) in static and RTK observation modes, while LiDAR data were obtained from an airborne platform and processed to generate a DTM. Spot height values were extracted from both DTMs at corresponding locations, and statistical analysis was conducted to determine the Root Mean Square Error (RMSE), Mean Error (ME), and Standard Deviation (SD). These metrics were used to quantify the vertical accuracy and evaluate the performance of each method. The results revealed that the LiDAR-based DTM achieved higher spatial coverage and reduced data collection time compared to the ground survey–based DTM. However, the ground survey–based DTM provided superior point-level accuracy in areas with dense vegetation or complex terrain where LiDAR returns were less reliable. Overall, the LiDAR-based DTM demonstrated efficiency and high accuracy for large-scale terrain mapping, while the ground survey–based DTM remained essential for detailed engineering and site-specific projects requiring precise elevation control. This assessment underscores the importance of selecting an appropriate DTM generation method based on project objectives, terrain characteristics, and required accuracy standards. The findings provide valuable insights for geospatial professionals in optimizing data acquisition strategies for topographic modeling and geospatial analysis.