In north-eastern and central India, land has been deforested and degraded by which type of agriculture?

Slash-and-burn agriculture is a farming method that involves the cutting and burning of plants in a forest or woodland to create a field called a swidden. The ash and debris leave a nutrient-rich layer of soil that makes it easier to grow crops during the next rainy season. However, it is not sustainable and has led to deforestation in north-eastern and central India.