The invention provides a method for calculating the
extinction coefficients of a three-dimensional forest
canopy under any given incident
ray by using a geometric
algorithm, belonging to the research field of a method of acquiring the structural parameters of the forest
canopy. The method for calculating the
extinction coefficients of the three-dimensional forest
canopy by using the geometric
algorithm comprises the following steps: acquiring and preprocessing the three-dimensional
laser-
point cloud data of a
plant canopy; carrying out three-dimensional gridding on the
point cloud data; carrying out
point cloud slice arithmetic based on a
voxel data structure; carrying out linear sampling analysis on the point cloud slices; calculating an average projection coefficient of a kth layer of slices; and calculating the
extinction coefficient of any given incident
ray in each layer of slices and the extinction coefficient of whole canopy. Compared with the traditional observing way, the invention has the characteristics of being small in working amount, and free from the contact observation and the damage of the canopy structure and
radiation, and has objectiveness, high efficiency and precision; a method of extracting the three-dimensional structures and biological and physical diversity information from the
laser radar data is developed to characterize the
horizontal and vertical distribution change rules of the leaves.