Response of radial growth of Pinus koraiensis in broad-leaved Korean pine forests with different latitudes to climatical factors.

Abstract

To reveal the radial growth trends of Pinus koraiensis and the differences in their responses to climate factors among different latitudes, and to assess the dynamic characteristics, adaptabi-lity and sensitivity of P. koraiensis under the influence of climate change, dendrochronological techniques were used to study the relationships between the climatic variables and the radial growth of P. koraiensis in broad-leaved Korean pine forests with different latitudes. The results showed that there were differences in the responses of the radial growth of P. koraiensis in four different latitudes to local climatic factors. In Baishilazi Nature Reserve, the southernmost sample plot, the radial growth of P. koraiensis was significantly positively correlated to the average relative humidity but significantly negatively correlated to the average maximum temperature of growing season. In low altitude of Changbai Mountain Nature Reserve, the intermediate sample plot, it was significantly positively correlated with precipitation, average relative humidity and PDSI, and significantly negatively correlated with the average maximum temperature in growing season. In Liangshui Nature Reserve, the intermediate sample plot, significantly positive correlations occurred for average relative humidity and PDSI in growing season, while significantly negative correlations occurred for the average temperature and the average maximum temperature in growing season. Nevertheless, in Shengshan Nature Reserve, the northernmost sample plot, it was positively correlated to the tempe-rature factors of most months. The climatic variables in June of current year were the main factors limiting the radial growth of P. koraiensis in all latitudes, and the average maximum temperature in June of current year was highly negatively correlated with radial growth for P. koraiensis measured at all sites. In recent four decades, with the rising of temperature, the radial growth of P. koraiensis decreased significantly in the southernmost point, increased significantly in the northernmost point, and did not change significantly in middle latitudes. The distribution area of P. koraiensis would be reduced if the temperature increased and precipitation remained unchanged in the future.