Research indicates that tropical montane forests (TMFs) are likely to be especially sensitive to climate change, given the distinctive climate conditions that occur in TMFs and models which predict large changes in these conditions. We remeasured 120 forest plots (each 500 or 1000 m2) spanning over 2000-m in elevation in the Cordillera Central, Dominican Republic to determine species-specific tree demography as a function of climate. We also characterized spatial patterns of species distribution and abundance – relative abundance when present, and the frequency within a particular climate where a species occurred. We sought evidence of functional groups of species with similar climate niche dimensions or if there are more individualistic distributions of species along the climate gradients. This research offers one of the first analyses of species-specific, climate–vegetation dynamics in TMFs.
Results/Conclusions
For most species, growth was much more sensitive to temperature than precipitation (PPT), while mortality patterns overall were driven by variation in PPT. Higher elevation species (occurring primarily >1750 m) display much stronger demographic sensitivity to both temperature and PPT than lower elevation species. Frequency varied strongly for nearly all species as a function of both temperature and precipitation, with most species having a Gaussian distribution along a climate gradient. The relative abundance for most species when present in a plot also varied markedly across their climatic ranges, and these patterns were highly individualistic (e.g. negative, positive, neutral). In general, our results suggest that processes that influence the presence of adults of a species (i.e., canopy recruitment and local extinction) will be particularly important in governing the forest dynamics in TMFs under climate change.