Forest Inventory and Biomass Assessment by the Use of Airborne Laser Scanning Method (example from Siberia)

The use of aerial laser scanning method provides a number of principally new possibilities on remote sensing of forest vegetation and specifically of a disturbed forest ecosystems (after wild fires, logging operations, insect outbreaks etc.) which area increases year by year in Siberia. The high efficiency of laser sensing survey (up to 50-70 thousand original measurements per second) combining with the spatial resolution and accuracy of a few centimeters allow making the effective algorithms of morphology analyses, ensuring automatic extraction of many important information characteristics of a disturbed forest ecosystems. The analysis of stand structure integrated with GPS data, digital aerial videoand highly accurate (10-15 cm of actual linear resolution) photographic images makes it possible to highly reliable interpretation of different types and layers of forest vegetation separating it by a tree species, density, degree of disturbance and other parameters. The consequent processing of laser profiling data and digital aerial photographs using original ALTEXIS software, integral calculations, the Fourier and mean free path analysis makes possible to get such important and precise information on vegetation as forest structure, tree species composition and timber stock at a direct way or by mediate on correlation with morphometric parameters. The regression method with the use of allometric functions provides accurate and effective assessment of stand biomass when processing a laser profiling data. The methodology aspects of airborne laser scanning method use for an aerial survey and biomass assessment at disturbed forests of Siberia are considered in the paper. The description of the morphology algorithms is shown. The results of practical application of airborne laser scanning by Optech Inc. ALTM-2050 machine for forest biomass evaluation in Central Siberia are discussed.