Unlike microbes, which were recently discovered to possess less adaptability to climate change than expected, a new study suggests that trees might possess more. The results reveal that forests adapt their carbon dioxide levels with climate change in order to deal with hotter temperatures.
Plants take in carbon dioxide during photosynthesis and release it during the respiration process. This respiration is responsible for six times as much atmospheric carbon dioxide than fossil fuel emissions, and until now, scientists believed that the temperature increases that come with climate change would lead to an increase in this release and thus an increase in warming.
The new study reveals that this may not be true. Plants are able to adapt their respiration process in order to deal with long-term temperature increases, leading to just a 5 percent increase in carbon dioxide emissions during these time periods when compared to normal conditions.
Using data from early studies that studied plant responses to short-term temperature changes, the team predicted that plants would release almost five times as much carbon dioxide under increased temperatures.
The team tested the respiration rates of 10 different boreal and temperature forest tree species located at two different forest-research sites in Minnesota and analyzed how they responded to increases in temperature over a time period of three to five years.
Two conditions were monitored: ambient (53 to 98 degrees Fahrenheit) and 38 degrees warmer than ambient. The scientists examined carbon dioxide release in the ambient condition, warmer condition and during a short period of time - lasting from minutes to hours - in the warmer condition.
The results revealed that the trees adapted to warmer temperatures released 80 percent less carbon dioxide in comparison to trees that were exposed to short-term increases in temperature, suggesting that they have the ability to adapt their respiration during periods of long-term climate change.
Although the findings are hopeful, they are just part of the full-story, according to Pierre Friedlingstein, a climate expert at Exeter University not involved in the current study.
"Global warming will also affect other plant properties -- e.g. photosynthesis, growth, mortality and reproduction -- and we are a long way from a complete understanding of the effects of rising temperatures on any of those processes," he said.
The findings were published in the March 16 issue of Nature.
