Forests healing from devastation of pine beetles: B.C. study
Published Monday, April 11, 2016 2:50PM PDT Last Updated Monday, April 11, 2016 6:05PM PDT
Mountain pine beetle larvae are shown in Twisp, Wash., Oct. 14, 2011. (The Seattle Times, Steve Ringman)
VICTORIA -- University of Victoria scientists say they have some good news about global warming and its impact on British Columbia's forests, especially about the environment's recovery from the devastating mountain pine beetle outbreak more than a decade ago.
A group of scientists at the university's Pacific Institute for Climate Solutions have discovered that global warming is producing larger trees and faster-growing forests.
The findings, published in the peer-reviewed scientific journal American Geophysical Union, conclude global warming is making B.C. forests grow faster and the trees in those forests are able to take in more carbon dioxide, the gas associated with the globe's steadily climbing temperatures.
"What we have found is the forests in B.C. are growing much faster than in the past due to climate change and increases in carbon dioxide, and this has helped us recover from the mountain pine beetle outbreak," said lead research Vivek, Arora, a climate modelling expert.
Under normal conditions, forests act as so-called carbon sinks, which scrub the atmosphere by pulling in CO2 while releasing oxygen, he said.
But during the pine beetle epidemic, which lasted from the 1990s up until 2005, 18 million hectares of dead and rotting pine trees pumped more carbon into the environment, turning the forests from carbon sinks into carbon sources.
Arora said as the outbreak waned, scientists found evidence of faster growing and larger trees emerging in B.C. forests. He said those trees are able to take in more CO2, leading the scientists to conclude the growing forests will compensate for the carbon emitted into the atmosphere by the beetle kill epidemic.
He said the trees will continue to grow larger and faster, but the look of the forest will not change drastically.
"We are not going to turn into an Amazon Rainforest," Arora said.
But the scientists' measurements have found that the trees and their branches have increased in size by up to three per cent over three years, he said.
"If the system keeps on doing what it has done over the past few years -- the last three or four decades -- then the implication of that is the carbon gained due to climate change had increased CO2 more than compensates for the loss associated with the pine beetle outbreak," Arora explained.