Effects of global warming on the potential distribution ranges of six Quercus species (Fagaceae)

Abstract

Abstract The impacts of global warming on the spatial extent and location of suitable habitat can be examined through spatially explicit projections of climatic niches. We modeled the climatic niche of six oaks (Q. agrifolia, Q. cedrosensis, Q. chrysolepis, Q. devia, Q. palmeri and Q. peninsularis), some rare and others widely distributed, occurring within the Baja California Peninsula, Mexico, and projected future distributions under two contrasting scenarios of global warming. We also estimated the breadth of the climatic niche of each species and associated it with current and future distributions. We found that climate warming will modify the distribution of suitable habitat for the six oak species, with considerable variation in changes among species. We observed that the breadth of climate niche is related to the potential geographic distribution of the species and that the loss of area under future scenarios of global warming is significantly correlated with the climatic niche size. To keep pace with climate change, oak populations will need to colonize new areas, because a large part of their present ranges will not retain suitable climatic conditions. The oaks are dominant elements in the Mediterranean-climate region and pine-oak forests of the Baja California Peninsula, so changes in their distributions will probably affect other species that closely interact with them. Further studies on the demography and ecological interactions of these oaks are recommended to refine predictions concerning effects of climate change and to identify conservation management options.