Long-term shifts in the functional composition and diversity of a tropical dry forest: a 30-yr study

Over the past three decades there has been a concerted effort to study the
long-term dynamics of tropical forests throughout the world. Data
regarding temporal trends in species diversity, species composition and
species-specific demographic rates have now been amassed. Such data can be
utilized to test predictions regarding the roles the environment and
demographic stochasticity play in driving forest dynamics. These analyses
could be further refined by quantifying the temporal trends in the
functional compostion and diversity in tropical forests. For example, we
have only a handful of studies that quantify directional shifts in the
functional composition in tropical forests in response to global change
drivers. The present study uses data from three censuses spanning 30 years
in a Neotropical dry forest dynamics plot to provide novel insights into
how the functional diversity and composition of a tropical forest has
changed through time.  Specifically, here we aim to: (i)
quantify population dynamics and compare it to that expected from
environmental or demographic variance; (ii) to quantify long-term trends
in species richness and functional diversity; (iii) test whether there
have been directional changes in the functional composition of the forest
though time and the population changes that are responsible for these
changes; and (iv) place these long-term results into the context of the
successional and climatic history of the forest.