Slash-and-burn

Slash-and-burn agriculture, or fire–fallow cultivation, is a farming method that involves the cutting and burning of plants in a forest or woodland to create a field called a swidden. (Preparing fields by deforestation is called assarting.) In subsistence agriculture, slash-and-burn typically uses little technology. It is often applied in shifting cultivation agriculture (such as in the Amazon rainforest) and in transhumance livestock herding.

Slash-and-burn is used by 200–500 million people worldwide. In 2004 it was estimated that in Brazil alone, 500,000 small farmers each cleared an average of one hectare (2.47105 acres) of forest per year. The technique is not scalable or sustainable for large human populations. Methods such as Inga alley farming have been proposed as alternatives to this environmental degradation.

Historically, slash-and-burn cultivation has been practiced throughout much of the world, in grasslands as well as woodlands.

During the Neolithic Revolution, which included agricultural advancements, groups of hunter-gatherers domesticated various plants and animals, permitting them to settle down and practice agriculture, which provides more nutrition per hectare than hunting and gathering. This happened in the river valleys of Egypt and Mesopotamia. Due to this decrease in food from hunting, as human populations increased, agriculture became more important. Some groups could easily plant their crops in open fields along river valleys, but others had forests blocking their farming land.

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