基于粗糙集理论的立地类型分类规则探讨

Classification Rule of Site Type Based on Rough Set Theory

利用粗糙集理论((R ough Set))中的知识表达系统和约简算法,在研究区内选取与立地因子关系最密切的树高因子为决策属性,以海拔、母岩、坡度、坡位、土类和土层厚度作为条件属性;决策属性动态聚类和各条件属性值域离散化后,建立立地类型分类决策表,计算决策属性的依赖度及其相对约简,得到马尾松林分立地类型的分类因子为土层厚度、坡位和母岩,并且其重要性分别为0.692 3、0.538 5和0.307 7.

Making use of knowledge presentation system and reduction algorithm in the theory of rough set, choosing in the study area tree height factors closely related to site factors as decision attributes, and taking altitude above sea level, parent rock, slope, slope site, soil type, soil level thickness as term attributes, the paper set up a site type classification decision table after the dynamic classification of decision attributes and the value dispersing of all sorts of decision attributes, and calculated the depending tolerance and relative reduction of decision attributes, thus defining classification factors of Masson Pine stand site type as soil level deepness, slope site and original rock, and its significance value is 0. 692 3, 0. 538 5 and 0. 307 7 respectively.