Deforestation (as for the sale of timber and make room for the sake of agricultural land ) is the main problem , it leads to a huge loss of natural economic wealth of the continent. Selective cutting of trees leads to a decrease in the quality of forests and biodiversity. Excessive use of non-timber forest products , including medicinal plants , increases the problem. In addition, there is concern that the illegal trade in exotic animals threatens a large number of mammals that live in the African bush . Pressure on forests and woodlands tougher because of the construction of access roads ( logging or mining companies ) that open forest, which increases the availability of resources and income from their use.