What does photogrammetry dsm mean?

Digital Surface Model (DSM) is a technical term in the field of surveying and mapping, which refers to the collection of digital expressions of the surface morphology of objects.

Digital elevation model is an exposed ground grid based on vertical datum. When the non-ground points such as bridges and roads are filtered out, a smooth digital elevation model will be obtained.

DEM excludes buildings (power lines, buildings and towers) and nature (trees and other types of vegetation).

When vegetation and man-made elements are removed from DSM elevation data, DEM will be generated, and bare land elevation model is particularly useful in hydrology, soil and land use planning:

Hydrological modeling: Hydrologists use DEM to describe river basins and calculate flow accumulation and flow direction.

Terrain stability: the area prone to avalanches is the high slope area with sparse vegetation, which is very useful in planning expressway or residential zoning.

Soil mapping: DEM helps to map soil, which is a function of altitude (as well as geology, time and climate).