陕西秦岭西段南坡油松林的数量分类

Quantitative Classification of Chinese Pine Forests on South Slop in the West Qinling Mountains

收集和调查了２９块油松林标准地伐前林分状况和代后天然更新状况。选取伐前和伐后树种组成，天然更新的密度、频度、坡位和土壤厚度等因子。通过聚类和排序等方法，将标准地分成３类，有力的支持了主观经验分类结果。分类的主要因子是伐前及更新中油松和阔杂的成数，坡位，土壤厚度。用伐前因子分类和上述分类结果相一致，最后构造了用伐前因子分类的判决函数。

Investigation on stand conditions before cutting and natural regeneration after cutting has been conducted at 29 Chinese pine(Pinus tabulaeformis)stands.According to the composition,density and frequency of natural regeneration,position on the slop and soil thickness,using cluster analysis and ordination,the stands could be divided into 3 types, which verified the results of subjective experience classification.The important factors available for the classification were composition of Chinese pine and trees with froad leave(excluding birch and oak)in natural regeneration before and after cutting, position on slop and soil thickness.The results between classification using factors before cutting and classification using factors before and after cutting are unanimous. Finally,using factors before cutting,the decision functions for classification of forest were composed.