Early Farming Methods Caused Climate Change, Say Researchers

From The Guardian:

Farmers thousands of years ago cleared land by burning forests and moved to a new area once the yields declined, say scientists.

Farmers who used "slash and burn" methods of clearing forests to grow crops thousands of years ago could have increased carbon dioxide levels enough to change the climate, researchers claimed today.

The US scientists believe that small populations released carbon emissions as they cleared large tracts of land to produce relatively meagre amounts of food.

They were much less efficient than farmers using today's agricultural practices because there were no constraints on land.

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