Large trees under threat: researchers

Saturday, April 23, 2016

Originally published at: 

While much of the focus lately has been the impact humans are having on the largest, and most spectacular reef in the world, slightly inland we are hurting one of our other greatest natural beauties.

Scientists from James Cook University and the Australian National University have released a paper detailing the threat to large, old trees.

Humans need to rush to protect large old trees under threat from our activities, researchers say.

These trees, defined as the top 5 per cent of reproducing trees in any particular place, play an enormous ecological role from storing carbon to giving possums somewhere to live.

Co-author of the paper, JCU's Distinguished Research Professor, Bill Laurance, said the role large old trees played was integral.

"They are the food basket or the grocery store of the forest," he said.

"They produce a huge amount of foliage and fruit that fertilise other trees or provide food for animals and birds.

"They produce hollow crevices that are homes for many species.

"They pump water up into the atmosphere which helps maintain cloud cover and maintain rainfall in many regions across the world."

But as humans continue to pump masses of carbon dioxide into the atmosphere these large, old trees also help battle against the damage we are doing to the environment.

"The obvious thing about large trees is they store a large amount of carbon," he said.

"If they are destroyed it has a major impact on climate."

While replanting younger trees is a good step towards ensuring there are large, old trees hundreds of years in the future, protecting the existing stock is also vital.

"A large tree will store, it depends what you are talking about, 100 or 1000 times as much carbon and many many times more water vapour and scores more foliage and fruit," he said.

"A lot of (younger, smaller trees) don't have hollows and there are many species that (need them).

"We have to protect places where large old trees survive."

Logging, land clearing, fire regimens, introduced pests and pathogens and climate change all have an impact on large, old trees' ability to survive and thrive.

"Unless we move fast, it's increasingly looking like there won't be very many places on Earth suitable for big old trees," Professor Laurance said.

"Personally, I hate the thought that my children might not be able to gaze in awe at a cathedral-like tree crown."

Professor Laurance said work needed to be done immediately to protect large, old trees and the forests they live in.

"We really need to be rethinking how we manage forests," he said.

"Large, old trees can survive... we have to prioritise their protection, we have to stop cutting down the large, old trees and we really need to rethink how we approach the conservation of large, old trees."

Categories: 

Subject: