We must cut carbon emissions by 80% from their 2006 levels by 2020, stabilize the world's population at eight billion by 2040, completely remove poverty, and restore forests and soils.

Predictions of the collapse of the tropical rain forests have been around for years.

Left alone, it was assumed, the world's rain forests would not only flourish but might even rescue us from disaster by absorbing the excess carbon dioxide and other planet-warming greenhouse gases

Some scientists believe that the rise in carbon levels means that the Amazon and other rain forests in Asia and Africa may go from being assets in the battle against rising temperatures to liabilities.

If the collapse of the rain forests speeds up dramatically, it could eventually release

billion metric tons of carbon into the atmosphere each year - making forests the leading source of greenhouse gases.

Trees need more water as temperatures rise, but the prolonged droughts have robbed them of moisture, making whole forests easily cleared of trees and turned into farmland

In the second paragraph, the author challenges the view that the collapse of rain forests is caused by direct human interference.

the collapse of rain forests is caused by direct human interference

the condition of rain forests has been rapidly deteriorating

rain forests should not be converted into pastures or farms

The author argues that the rising carbon levels in rain forests may turn them into a major source of greenhouse gases.

What has made it easier to turn some rain forests into farmland

The domino effect triggered by the perishing rain forests.

Its practice of burning forests for settlement and development

We can turn the most luxuriant forests into throwaway paper products.

Even though the nuts, which need to stay moist, can be somewhat delicate to transport, traders carried them hundreds of miles throughout the forests and grasslands.

The reason for constructing the buildings from wood is probably that ideally proportioned straight and slender timber was available in large quantities in Scandinavia's vast pine forests.