Mature oak trees will increase their rate of photosynthesis by up to a third in response to the raised CO2 levels expected to be the world average by about 2050, new research shows.
Mature oak trees will increase their rate of photosynthesis by up to a third in response to the raised CO2 levels expected to be the world average by about 2050, new research shows.
The results, published in Tree Physiology, are the first to emerge from a giant outdoor experiment, led by the University of Birmingham in which an old oak forest is bathed in elevated levels of CO2. Over the first three years of a ten-year project, the 175-year-old oaks clearly responded to the CO2 by consistently increasing their rate of photosynthesis.
Researchers are now measuring leaves, wood, roots, and soil to find out where the extra carbon captured ends up and for how long it stays locked up in the forest.
The increase in photosynthesis was greatest in strong sunlight. The overall balance of key nutrient elements carbon and nitrogen did not change in the leaves. Keeping the carbon to nitrogen ratio constant suggests that the old trees have found ways of redirecting their elements, or found ways of bringing more nitrogen in from the soil to balance the carbon they are gaining from the air.
Read more at University of Birmingham
Image: University of Birmingham researcher Anna Gardner taking CO2 measurements in the forest canopy (Credit: University of Birmingham)
