Growth of Pinus cembroides Zucc. in Response to Hydroclimatic Variability in Four Sites Forming the Species Latitudinal and Longitudinal Distribution Limits

Climate change modifies the distribution and dominance of forest tree species, particularly near their distribution limits. This study used tree-ring width data for Pinus cembroides Zucc. at ts distribution limits in Mexico and the SW USA to assess how tree populations responded to hydroclimatic variability. Indexed ring-width chronologies were built and correlated with climate and drought records at four marginal stands. We found that P. cembroides responds differently to climatic conditions depending on the bioclimatic and biogeographic conditions, with the forests situated in the driest area (Nuevo León) presenting the highest growth association to maximum temperatures and drought, while the forest situated in the wettest area (Puebla) was the least correlated to these hydroclimatic factors. In particular, dry and hot conditions, during the prior autumn and winter, reduced radial growth. Drought conditions could result in more vulnerable forests at the driest sites. These results advance our understanding of the radial growth responses ofP. cembroides and similar widely distributed trees to climatic change near their biogeographical limits.To CSIC Agency (Spain) for support.Peer reviewe