Applications of Multi-temporal DTMs in Mining Management and Environmental Analysis

The mining industry, which encompasses national resource management, environmental and ecological impacts, is becoming increasingly important to sustainable development policies. Digital Terrain Model (DTM) provides a spatial distribution of numerical terrain features and the ways in which the model can be constructed and mapped have evolved through a variety of technologies, including aerial photography, airborne LiDAR and drone mapping, DTM can be subdivided into Digital Surface Model (DSM) and Digital Elevation Model (DEM). This study therefore proposes to integrate multi-technology DTMs with terrain metrology analysis to accurately define the land use profile of a mine site over time to provide transparent land use information and monitor environmental changes. In addition to estimating assessment of the mine site is investigated, and vertical accuracy analysis based on spatial grid sampling and the 2018 airborne LiDAR DEM is conducted to assess the error between data to calculate surface volume variation and demonstrate elevation profile changes. According to the results of the accuracy analysis, the 2003 aerial photography DTM showed a larger average error of -0.19 m with a standard deviation of ±1.71 m compared to the airborne radar and UAV; the 2015 airborne radar DEM showed an average error of 0.00 m with a standard deviation of ±0.11 m; and the 2022 UAV DSM showed an average error of 0.00 m with a standard deviation of ±0.10 m. Aerial photographic DTMs can demonstrate the early geomorphology of the study area; airborne LIDAR DEMs can present a wide range of high-precision and high-resolution topographic information features that can penetrate vegetation; and UAV DSMs can reflect regional surface changes, such as mining volume variation in open pit mines.