Differences in climate and drought response of the exotic plantation species Abies firma, Cryptomeria japonica, and Chamaecyparis obtusa in southern Korea.
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, and Chamaecyparis obtusa, to regional moisture conditions during the dry spring and wet summer in plantations located in south-central Korea. We examined the growth response of A. firma, C. japonica, and C. obtusa to monthly precipitation and drought indices from 1950 to 1998 using tree-ring analysis. The radial growth of A. firma showed 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 in A. firma. In contrast, C. japonica and C. 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 of C. japonica and C. 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.