Differences in climate and drought response of the exotic plantation speciesAbies firma, Cryptomeria japonica, andChamaecyparis obtusain southern Korea

Abstract

Exotic species plantations are increasing for timber production and other economic benefits. However, evaluation of species adaptation to local climates requires long-term research and the information is still limited. This study was conducted to understand the growth response of three exotic tree species,Abies firma, Cryptomeria japonica, andChamaecyparis obtusa, to regional moisture conditions during the dry spring and wet summer in plantations located in south-central Korea. We examined the growth response ofA. firma, C. japonica, andC. obtusato monthly precipitation and drought indices from 1950 to 1998 using tree-ring analysis. The radial growth ofA. firmashowed a significantly positive relationship with precipitation and drought indices in spring (p< 0.05). Water stress in spring was the main limitation to radial growth inA. firma. In contrast,C. japonicaandC. obtusa, with indeterminate growth, had negative correlations with precipitation and drought indices in summer (p< 0.05). Abnormally high summer precipitation may interrupt photosynthesis by reducing sunshine duration and evaporation, negatively affecting the growth ofC. japonicaandC. obtusa. The different responses of these species to monthly precipitation and drought indices imply that regional precipitation patterns should be carefully considered in species selection for the establishment of exotic species plantations.