The Amazons biggest trees are dying
The Amazons biggest trees are dying. Really? Forest coroners investigate. As tropical forests are degraded and decline at increasing rates the world over, the fate of these forests’ largest trees remains unknown. Big trees store a huge amount of carbon, so assessing their current mortality rates and causes of death (especially due to escalating climate change) is vital to calculating how much tropical forest carbon sinks could decline in the future. In perspective too, the biggest trees are quite likely to be the oldest trees. This in part may be why the Amazons biggest trees are dying.
{Earth and Leaf Editorial}
The Amazons biggest trees are dying – we have to understand why?
Forest coroners investigate why the Amazons biggest trees are dying
- As tropical forests are degraded and decline at increasing rates the world over, the fate of these forests’ largest trees remains unknown.
- Big trees store a huge amount of carbon, so assessing their current mortality rates and causes of death (especially due to escalating climate change) is vital to calculating how much tropical forest carbon sinks could decline in the future.
AMAZONAS, Brazil: Two researchers wearing long-sleeved shirts and pants to resist mosquitos, and high boots to block snake bites, gaze at a shattered tree. It lies on the ground garlanded in palm fronds, stretching far into the forest. Until recently, it had towered over most other trees in this vast rainforest.
“It’s lightning, obviously,” says Evan Gora, declaring the tree’s cause of death. He’s a staff scientist at the Cary Institute of Ecosystem Studies in Millbrook, New York.
“You can see burned leaves on the top,” agrees Adriane Esquivel Muelbert. She’s a professor at the University of Birmingham in England. Adriane points up at blackened foliage dangling from 20 trees circling the perimeter of the huge stump. The leaves are seared only on the sides facing the canopy gap left when the big tree toppled — evidence of an electrical strike.
Like Sherlock Holmes unraveling a murder mystery, the tropical forest ecology experts present their reasoning to two postdocs on their team. When lightning hits a tree, Evan says, high voltage flows through intertwined foliage into neighboring trees, killing branches, creating a distinctive pattern. Evan developed this method for determining lightning as a cause of tree death while working in a Panamanian rainforest. Today, he’s identified the same radiating pattern of scorched dead vegetation here around this fallen giant in the Brazilian Amazon. No other cause of tree death looks like this.
“You sometimes can have many trees standing dead together, but not with this centralized [burn] damage,” Adriane comments.
“It’s like a crime scene investigation,” Evan says, with growing enthusiasm.
It may seem odd for two high-powered scientists to spend so much time forensically investigating a single tree’s death in a vast forest. But the implications are weighty. Their research project, Gigante, is exploring the causes of mortality in the biggest trees of the world’s tropical forests. It could help answer a consequential question of climate change science: Will intact tropical forest continue soaking up far more carbon dioxide than it releases?
This is a great video, Anatomy of a fall – why is it that the Amazons biggest trees are dying?
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