ANALYSIS METHOD OF NATURAL FOREST DISTRIBUTION PATTERN BASED ON ARTIFICIAL IMMUNE ALGORITHM AND GRID SEARCH

摘要

Correctly describing the spatial pattern of forest trees is the basis for determining the distribution of forest trees. This paper analyzed the spatial distribution pattern of forest trees in typical natural broad-leaved secondary forest in the Dongting Lake area in China. Firstly, the position of the tree was adopted as a point target in the forest trees coordinate system. Then, we applied the grid theory and artificial immune algorithm to search the optimal grid of the forest trees, and then got the grid-degree ratio of the optimal grid. Finally, we used the grid- degree ratio as an important indicator for judging the spatial pattern of forest trees. The results of Spearman correlation analysis showed that the gird- degree ratio of the optimal grid depends strongly on the clustering index, angular scale and Voronoi coefficient of variation. Therefore, it is completely feasible to use the optimal grid method as the evaluation index of the spatial pattern of forest trees. Overall, we proposed a method based on the optimal grid to analyze the spatial pattern of forest trees. Such a method we proposed clarified effectively the spatial distribution pattern of forest trees by means of the horizontal distribution characteristics of forest trees.