2021 ESA Annual Meeting (August 2 - 6)

Species composition and climate dynamics drive aboveground wood productivity in tropical forests of Colombia

On Demand
Zarith Villamizar-Gómez, Biology, Universidad Industrial de Santander;
Background/Question/Methods

Tropical forests are an important component of the carbon cycle. They account for one third of global net primary productivity because of favorable conditions for plant growth, such as relatively stable and benign climate, high and constant amounts of solar radiation throughout the year, and high levels of biodiversity. In Colombia, however, the Andes divide into three, giving rise to a wide range of climatic conditions, including their temporal dynamics, high levels of beta diversity, and a diversity of forest ecosystems. This makes Colombia ideal to study the effect of climate and biodiversity on forest growth. Here we analyze the effect of climate and biodiversity on the dynamics of aboveground wood productivity (AGWP) across 20 forest plots located in different ecoregions of Colombia over the last 25 years. To do so, we determine the importance of 8 climatic variables associated with the temporal dynamics of temperature and precipitation and 4 biodiversity variables using linear mixed-effects models and variable selection.

Results/Conclusions

We find that the main driver of AGWP is species composition followed by temperature variability over the study period. Precipitation and temperature trends indicating climatic changes had a weak but significant effect. Variables such as species richness, Shannon diversity, mean annual temperature and annual precipitation had no explanatory power in our analyses, which contradicts previous findings in tropical forests. Our results suggest that species composition and beta diversity across Colombian forests are important drivers of AGWP and that temperature increase over the last 25 years likely had a positive effect on AGWP. Our findings highlight the importance of studying the temporal dynamics of climate and the effect of biodiversity loss to better understand the primary productivity and carbon cycling of tropical forests.