DISTRIBUTION OF FOREST VEGETATION AND CLIMATE IN THE KOREAN PENINSULA : III. DISTRIBUTION OF TREE SPECIES ALONG THE THERMAL GRADIENT

Abstract

YIM, Yang-Jai (Dep. Biol., Coll. Lib. Arts & Sci., Chungang Univ., Seoul). 1977. Distribution of forest vegetation and climate in the Korean Peninsula. III. Distribution of tree species along the thermal gradient. Jap. J. Ecol., 27 : 177-189. The distribution of 50 woody plant species along the gradient of thermal climate was studied using existing records of their three-dimensional distribution in the Korean Peninsula. The range and frequency of occurrence of the species were examined in relation to KIRA's warmth index (WI). The frequency-WI curves obtained were found to be bell-shaped and more or less symmetrical with a single maximum. The range of thermal distribution of a species was 30-60 (mostly 40-50)℃ month in terms of the WI. The species were grouped into the following 4 groups according to the optimal ranges of their thermal distribution ; subalpine, cool-temperate, warm-temperate deciduous and warm-temperate evergreen group. Unlike other groups, the northern or upward limits of distribution of the species of the last group proved to be most closely correlated with the coldness of winter as expressed by KIRA's coldness index.