A new study by Florida State University’ Stephanie Pau reveals tropical forests bloom with slight temperature increases. The study shows how changes in temperature, cloud cover and rain affect the number of flowers. Clouds apparently have an effect on short-term seasonal growth but longer-term changes seem to be down to temperature.
Flowering forests are a sign of good health
The number of flowers a rainforest produces is a sign of its health. But there’s a tipping point where a forest gets too hot, at which point plants produce fewer flowers. While there’s no sign of it happening yet, it appears the future health of rainforests depends on how much the tropics continue to warm.
Satellite data integrated with on-site observations
The research integrated on-the-ground observations with satellite images over almost thirty years, which the team used to analyse the influence of temperature and cloudiness and identify which has what effect. And it confirms previous studies, which have also shown that modest warming can have a dramatic effect.
Comparing numbers of flowers
The team of international researchers looked at seasonal and year-on-year flower numbers in two very different rainforests. One was a seasonally dry forest on Barro Colorado Island off Panama, the other was a permanently wet rainforest in Luquillo, Puerto Rico. The dry site produced 3% more flowers every year for the past 30 years, indicting the change is down to warmer temperatures rather than increases in cloud.
Temperature is the biggest threat
The research team’s leader Stephanie Pau said, “The amount of sunlight reaching tropical forests due to varying amounts of cloud cover is an important factor, just not the most important when it comes to flower production. Clouds are a huge uncertainty in understanding the impacts of climate change on tropical forests. Both sites still appear to respond positively to increases in light availability. Yet temperature was the most consistent factor across multiple time-scales.”
The conclusion? While the tropics won’t experience the same temperature increases as places in higher latitudes, tropical forests are still extremely sensitive to small changes.
Image courtesy of Flickr.