Estimation Forest Stand Crown Based on High Spatial Resolution Imagery

The crown is an important tree measurement factor of the forest stand. Estimating forest canopy based on high-resolution remote sensing images is an important research topic that has attracted much attention in recent decades. This paper proposes two methods of extracting stand crown widths based on different stand densities based on high spatial resolution satellite remote sensing images (QuickBird) of the Baisha artificial fir forest in Minhou, Fujian. For high-density forests, where the crowns are not easily distinguishable on the image, a method is proposed to estimate the average crown width using the semi-covariance function of the image slice based on the spatial structure of the canopy on the high-resolution image; for low-density forests, where the crowns are easily identifiable on the image, a method is proposed to extract the crowns and calculate the crown widths using the vegetation index contour combined with the maximum point of crown reflectance.