According to a disturbing new report, the world's oldest and largest trees may be dying off -- and fast.
The study determined that trees between 100 and 300 years old are perishing "en masse" because of a deadly combination of large destructive events like forest fires, and other, more incremental factors like drought, high temperatures, logging and insect attack. The steady increase in threats means old trees are dying at 10 times their normal rate, researchers concluded. Their study appears in the Dec. 7 issue of the journal Science.
“It’s a worldwide problem and appears to be happening in most types of forest,” explained lead author David B. Lindenmayer, of Australian National University, in a release. "Large old trees are critical in many natural and human-dominated environments."
The scientists originally discovered a "very, very disturbing trend" while inspecting Swedish forestry records from the 1860s, then realized forests in Australia, California's Yosemite National Park, the African Savannah, Brazilian rainforests, and other regions of Europe had also suffered large losses of old trees.
Critically, "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."
They also capture and store significant amounts of carbon, notes The Telegraph, and recycle surrounding soil nutrients, which in turn encourages new growth.
Scientists warn that unless an urgent "world-wide investigation" can assess the loss and create conservation programs with time-frames that span centuries, the world's oldest trees are gravely imperiled.