Pinus yunnanensis is an important commercial timber tree species in southwestern China. Investigation on the radial growth of P. yunnanensis at different elevations and their responses to climatic factors is essential for understanding climatic sensitivity and adaptation of this economical important species under global climate change. We collected tree increment cores of P. yunnanensis from two elevational sites in the Yulong Snow Mountain, northwest Yunnan Province, China. Two ring-width standard dendrochronologies were developed using traditional dendrochronological techniques and their growth-climate correlations were analyzed. The results showed that 1) P. yunnanensis at lower elevation site grew faster than those at higher elevation site. 2) Radial growth of P. yunnanensis correlated positively with precipitation, relative humidity, and the Palmer Drought Severity Index (PDSI), but correlated negatively with air temperatures during the early growing season from May to June. 3) The sensitivity of radial growth of P. yunnanensis to moisture availability differed between different elevations, with higher positive correlations between tree-ring chronology and precipitation, relative humidity, and PDSI at lower elevation than that of higher elevation. These results demonstrated that radial growth of P. yunnanensis in the Yulong Snow Mountain was mainly limited by moisture availability during the late spring and early summer season. Regional warming and drying climate may have negative effects on tree growth of P. yunnanensis, especially at low elevations. Our results provide important implications for understanding potential distribution shifts of P. yunnanensis under future climate changes, as well as sustainable management of pine plantations in southwest China.
Acta Ecologica Sinica