Radial growth responses of three conifers to climate in Lugu Lake, Northwestern Yunnan

Abstract

Climate change significantly influences tree radial growth, particularly in high-elevation forests. Using dendrochronological methods, we constructed residual chronologies from tree-ring width data of Larix potaninii Batalin. (Chinese larch), Picea likiangensis Franch. (Lijiang spruce) and Pinus yunnanensis Franch. (Yunnan pine) collected around Lugu Lake. We used Response Function Analysis (RFA) and Redundancy Analysis (RDA) to quantify growth–climate relationships. We further identified the key climatic drivers of radial growth for the three conifer species. The results showed that: (1) The radial growth of L. potaninii, P. likiangensis, and P. yunnanensis around Lugu Lake was jointly influenced by temperature and precipitation. Specifically, the mean minimum temperature (Tmin) of previous September, current January precipitation, the mean temperature (Tmean) of current May, and the mean maximum temperature (Tmax) of current September were common factors influencing the radial growth of three conifers. L. potaninii was more influenced by temperature in the early growing season (April–May) and moisture conditions in the post growing season (September– October). Elevated growing-season temperatures were detrimental to the growth of P. likiangensis. P. yunnanensis was more affected by spring drought stress and summer precipitation. (2) Under projected warming with slightly reduced precipitation, the observed climate sensitivities suggest that growth of L. potaninii and P. likiangensis may respond differently, whereas the response of P. yunnanensis is likely more complex. RFA and RDA demonstrated consistency and could effectively complement each other in dendroclimatological studies. This study provides new tree-ring evidence from northwestern Yunnan and insights into potential future growth responses in the region under climate change.