sOIL and deforestation
Since 1978 over 750,000 square kilometers (289,000 square miles) of Amazon rainforest have been destroyed.
The soil is several meters deep; however most of the nutrients that plants require are located within the topsoil. The topsoil receives its nutrients through a cycle where dead plants and animals are decomposed, and are then used by the other vegetation as nutrients. In general, however, the soil in the Amazon is very poor. Deforestation by humans leaves the topsoil very vulnerable soil erosion, which would result in other plants being unable to receive even the small amounts of nutrients there.