Global Warming the New Fertiliser
A recent study suggests that trees are growing faster as a result of global warming. In one of the forests, located at Maryland, US, researchers discovered that an extra 1.8 tonnes of timber per acre is appearing there each year. The scientists predict that the tree saplings are sprouting up more quickly than at any time in the past 225 years.
The scientists explained in the study that the accelerated growth was down to three factors. One the rising levels of atmospheric carbon dioxide, two higher temperatures and three longer growing seasons. Researchers spent more than 20 years tracking the growth of 55 stands of mixed hardwood forest plots to make this discovery. They found that more than 90% of the stands were found to have grown two to four times faster than expected.
Ecologist Geoffrey Parker, from the Smithsonian Environmental Research Centre in Edgewater, Maryland, said: “We made a list of reasons why these forests could be growing faster and then ruled half of them out.” He went on to say that the best explanation was a response to climate change.
Over the length of the study carbon dioxide levels had risen by 12%, average temperatures had increased by nearly three tenths of a degree and the growing season had lengthened by 7.8 days. This meant that the trees had more carbon dioxide to help them obtain energy from the Sun and an extra week in which to grow.
You can find out more about these findings in the journal Proceedings of the National Academy of Sciences or you can follow this link http://www.pnas.org/
