Abstract
Foliage estimation from laser scanning data has limitations caused by the occluded space of beams in a canopy and high cost of the scanning. We focused on twigs supporting leaves, and developed an estimation method for three-dimensional foliage distribution with low-cost laser scanning under leafless conditions. To validate the scanning method, we used the method for the canopy of a secondary Fagus crenata forest and applied a contact point quadrat method to the canopy. Vertical leaf distribution from scanning during leafless season was very similar to that of the contact method, and the three-dimensional leaf distribution from the scanning showed a smooth trend of leaf area density within a canopy volume of 1.8 × 1.8 × 0.6 m3. These results were caused by the smaller proportion of occluded space and substantial reduction of estimation error per beam length. We can reduce the cost of our scanning system because of its minimal requirements. The concept of scanning during leafless season might have the potential to contribute to scanning with a high-resolution scanner by complementing the occluded space in an existing foliage estimation method using our estimation method.
