(MintPress) – What do fire, logging, drought and disease all have in common? Ecologist David Lindenmayer of Australian National University says they are all responsible for the world’s biggest and oldest living trees dying off at an alarming rate — 10 times higher than normal — and all involve human intervention. The lead author of a recent study published in the journal “Science,” Lindenmayer called the loss of the giant trees, aging between 100 and 300 years old, a “global phenomenon,” adding there is a need to restore historic levels of the trees since they are essential bedrocks to forest ecosystems.
Trees act as giant lungs, soaking up masses of carbon dioxide in the air. If they die in mass, climate change would worsen. According to the Global Carbon Project, trees remove more than 50 percent of carbon dioxide created by humans, and when they die, all of the carbon they stored is released as they decompose.
“Big, old trees are not just enlarged young trees,” Jerry F. Franklin of the University of Washington, another of the study’s authors, told the New York Times. “Old trees have idiosyncratic features — a different canopy, different branch systems, a lot of cavities, thicker bark and more heartwood. They provide a lot more habitat and niches.”
In their study, the scientists reported nearly a third of all birds, reptiles, mammals and marsupials make their homes in ancient trees. Giant trees are also able to capture and store significant amounts of carbon and recycle surrounding soil nutrients, which encourages growth in the forest ecosystem. Similarly when there is a wildfire or a windstorm, older trees trigger the recovery process by providing seeds as well as habitats for other species so the forest can “re-establish itself.”
Lindenmayer said he became interested in the fate of trees while studying the Leadbeater’s possum, a marsupial that can only nest in ash trees at least 200 years old. Unless the ancient ash trees are saved, Lindenmayer said he fears the possum is headed for extinction.
Oregon State University Professor Mark Harmon told the Seattle Times that forestry experts have been aware for a while that big trees have been in decline, but added that the study was the first to make the argument that big trees deserve special consideration to be saved.
Likening the loss of the trees to the near extinction of tigers, elephants and whales, Lindenmayer said, “Big trees can be lost very quickly, but it can take centuries for them to be replaced.” He pointed out that despite decades of programs to rebuild populations of near-extinct animals like the blue whale, the species is still hovering on the brink of extinction.
The authors of the study have requested a worldwide investigation into the loss of the trees, the creation of protected areas where the trees have a chance to survive and for nations to plant new trees.