The ‘Algemeen Hoogtebestand Nederland’ (AHN ) is a publicly open available Digital Elevation Model with national coverage in the Netherlands. The AHN can be used for estimating the height of objects as is already done by Alterra (OHN). The method they developed is an example of how the heights of objects, like houses or stand-alone trees, can be derived. Their method however isn’t really optimized for vegetation structures and in practice underestimates the height of e.g. trees.
Having a general-purpose Digital Surface Model (DSM) and Digital Terrain Model (DTM) based on the AHN, one might be interested in a Canopy Height Model or other forms of vegetation representation. This thesis topic aims to develop a method for deriving a general-purpose CHM or vegetation representation from the AHN pointclouds.
Several reasons and applications can be thought of for developing a vegetation map. For this thesis the purpose of the CHM is rather general: mapping the presence, height and ‘green volume’ of vegetation in the Netherlands. Important note is that the focus will not be on only individual trees, rather also on groups of trees, bushes and other vegetation structures.
- Exact research questions and objective will be formulated after brainstorm with the supervisor
Turn AHN 3 pointclouds into
- Raster-based Canopy Height Model
- 3D vegetation models
- Scripting skills for reproducibility and scaling up of your work (Geoscripting)
Theme(s): Sensing & measuring; Integrated Land Monitoring