%0 Articles
%T Airborne laser scanning based identification and interpretation on ecologically important old-growth forest habitats in natural conservation areas
%A Vehmas, Mikko
%D 2011
%J Dissertationes Forestales
%V 2011
%N 120
%R doi:10.14214/df.120
%U http://dissertationesforestales.fi/article/1903
%X Over the last decades, accurate and cost efficient remote sensing techniques in large-scale forest inventories have developed rapidly. In particular, the airborne laser scanning (ALS) has provided new possibilities to quickly and accurately monitor forest ecosystems over large areas. ALS provides three-dimensional data on forest structure and is already applied in the stand level management inventory in many countries. My study focuses to tests the potential of ALS to facilitate biodiversity inventories that have not yet been entirely assessed.

The data used in this thesis was collected from the Koli National Park (Koli NP) in eastern Finland and included 274 mature forest stands belonging to five different forest site types. The longevity of aspen stands was studied based on multi-source data. About one-third of the old-growth forest areas of the Koli NP contained large aspen trees that persisted throughout the period between 1910 and 2004, which shows that aspen can maintain long-term occurrence in old-growth forests.

The ALS was used to identify herb-rich forest stands. ALS was capable of distinguishing herb-rich forests from less fertile site types with an accuracy of 88.9%. This was mainly based on the vertical vegetation profiles that characterize forests on high fertility sites. The best overall classification accuracy achieved for all the forest site types was 58.0%. As a basis on earlier studies canopy gaps can be located using ALS data. I found clear differences between the canopy gaps of natural forests and managed forests. In addition, both the density of vegetation and amount of coarse woody debris are utilizable characteristics in the ALS data-based identification of canopy gaps. In the large-scale forest inventories ALS-data proved to be a useful technology for the identification of several forest characteristics related to biodiversity in old-growth boreal sites.