Airborne laser scanning performance analysis in the forest stand map production

Stand height information, a significant parameter for forest inventory, is widely obtained with acquiring single tree information with geodetic techniques in underdeveloped or developing countries like Turkey. Acquired single tree information is generalized for whole forest stand with high error rate estimations. Developed countries, especially America and European countries, have completely excluded terrestrial methods with a high margin of error in forest stand height determination studies with the development of modern measurement technologies based on remote sensing (RS). This study aims to produce forest stand height map with airborne laser scanning (ALS) dense point clouds and to reveal the absolute location accuracy potential of the produced map. For this purpose, a forest-dominant study area was selected in Houston, USA, digital surface and terrain models were produced with ALS data, and a three-dimensional forest stand height map was obtained using a normalized digital surface model technique. The accuracy of the map produced was evaluated with model-based approaches using the forest stand height map produced with the data obtained from terrestrial laser scanning (TLS) technique in the same study area. International accuracy metrics for standard deviation and normalized median absolute deviation were used in the evaluations. In the light of the results, it has been determined that the stand height map produced with ALS data has an absolute position accuracy of +/- 1 cm horizontally and +/- 40 cm vertical.