Climate change linked to more flowery forests?

The researchers studying the rich tropical forests of Panama's Barro Colorado Island found that climbing rates of carbon dioxide have set the stage for a multidecade increase in overall flower production.

"Over the past several decades, we have seen temperatures warming and carbon dioxide increasing, and our study found that this tropical forest has responded to that increase by producing more flowers," said Stephanie Pau, from the Florida State University in the US.

The findings suggest that tropical forests, which have evolved over millennia to flourish in warm, equatorial conditions, may be more sensitive to subtle climatic changes than some ecologists predicted.

"Tropical forests have evolved in generally stable climates," Pau said.

"So while they may not be warming as much as some higher-latitude ecosystems, these tropical species appear to be much more sensitive than we might have expected," Pau said.

For the study, published in the journal Global Change Biology, the researchers evaluated a record of plant material collected and archived by researchers on the island over 28 years. They then examined how a host of climatic drivers - temperature, rainfall, light and carbon dioxide - appeared to affect the annual flowering activity and flowering duration of the different species present in the forest.

"What we were able to do in this paper is ask why flower activity has been increasing over the long term," Pau said.