Integration of remote sensing data into forest inventory in close-to-nature forests: An initial case study in Smolnicka Osada, Slovakia.

The initial case study concerns the first assessment of possibilities of integrating remote sensing into forest inventory in Slovak close-to-nature forests. Aerial images and airborne laser scanning data were used to estimate forest stand characteristics, such as the number of trees, mean tree height, mean tree diameter, and growing stock. eCognition software for tree species classification and reFLex software for individual tree detection was used. The accuracy of the assessment was conducted in the ProSilva object Smolnicka Osada (Eastern Slovakia, Central Europe), which has been under selective management for more than 60 years. The ALS data were obtained with a Leica RCD30 scanner from an average height of 1,034 m with a point density of 4 echoes per square metre. The ground reference data contained the measured positions and dimensions of 924 trees in 35 plots distributed across the region. It was found that the difference between the remote-based results and ground data was -50 percent for the number of trees, 8 percent for mean height and diameter, and -28 percent for growing stock.