Conserving rainforests needs re-think



Climate change is poised to wreak havoc on tropical rainforests, but conservation groups and international aid donors may be on the wrong course to reduce these threats, according to a group of leading ecological scientists.

The latest edition of the prestigious journal Nature publishes a letter from the scientists arguing that the world needs to rethink the application of conservation tools if it is to improve the resilience of tropical forests against climate change.

Tropical rainforests sustain most of the world\’s terrestrial biodiversity and among the host of threats to these ecosystems, climate change is looming ever larger. Scientists are currently trying to understand how rising temperature and altered rainfall will affect forests.

But Dr Jedediah Brodie from the University of Montana, Professor Eric Post of Pennsylvania State University, and James Cook University’s Distinguished Professor William Laurance say that this misses a critical point.

A far greater threat, they say, is that climate change could increase destructive forest fires or pressures from industrial logging.

\”Many tropical trees are resistant to modest temperature increases and even drought. But if these changes lead people to set more fires, rainforests could be devastated,\” says the study\’s lead author, ecologist Dr Brodie.

\”This effect may be vastly more harmful than the impacts of climate change alone.”

Professor Laurance said that in places like the Amazon and Southeast Asia, drying conditions made it far easier for people to burn forests for farming.

“Even small fires can escape and inadvertently destroy far larger areas,” he said.

“Intense rainy seasons wash out roads or make dirt tracks unusable. But when rainfall declines, people can get into even remote areas, increasing pressure on the forests through logging, hunting, and burning.”

The authors argue that slowing deforestation and controlling fires are critical for reducing the impacts of climate change. This can best be achieved by using international carbon trading to protect large, intact expanses of tropical forest.

But at present, such efforts are not being coordinated at the regional or international scales needed to achieve these aims.

Professor Post said that billions of dollars were available to slow deforestation and thereby reduce carbon emissions.

“But we need to focus on creating really big protected areas, especially those that span large gradients in elevation or moisture, so that species can migrate as climates change in the future,” he said.

Dr Brodie said that on its own, climate change could stress tropical forests.

“But when you add in human-lit fires and increased logging, it’s like hitting them with a sledgehammer,” he said.

“Small, isolated parks won’t be big enough to withstand these pressures. If we’re going to protect tropical biodiversity in the long term, we need to think really, really big.”