LiDAR DTM: artifacts, and correction for river altitudes

lidar data provide high-resolution Digital Elevation Models (dems), but some artifacts affect their accuracy and precision. This includes the dems generated by the Mexican National Institute of Statistics and Geography (Instituto Nacional de Estadisitica y Geografia, inegi), especially lidar Digital Terrain Models (dtms) related to the bare earth surface. These artifacts correspond to triangular facets observed in different small and scattered areas, as well as on the surface of the rivers. When dense gallery forests are present, river surfaces have a high roughness also associated with multiple triangular facets. The treatments developed in this research mitigate and/or eliminate these drawbacks and improve the lidar dtms. Calculations based on the elevation Root Mean Square Roughness and the elevation Root Mean Square Error confirm that the method presented here allows dtm products to be improved in order to realize accurate simulations and precise measurements.