Study shows trees absorb less carbon than earlier thought; leaf activity drops during summer

Phys.Org: On the first day of summer -- the longest day of the year -- tree leaves are lush and green, luminous in the June sunlight. Yet just a day after the summer solstice, length of daylight begins to incrementally decrease; tree leaves begin to shut down, and the activity of photosynthesis declines. As the season progresses, this drop in photosynthetic activity means trees absorb less carbon dioxide than they had on the longest day of the year and ultimately sequester far less carbon on a global scale...

URL: http://phys.org/news/2012-05-trees-absorb-carbon-earlier-thought.html