Which of the following has been a primary cause of soil depletion in deforested rain forest environments?

Which of the following has been a primary cause of soil depletion in deforested rain forest environments?

• A. The overuse of harmful pesticides
• B. The introduction of cash-crop agriculture
• C. Contamination by industrial waste
• D. The use of chemical fertilizers

Answer: (B)

When a rainforest is cleared and converted to a cash-crop system, the main reason soil fertility declines is the loss of protective vegetation and the move to a single-crop, high-demand land use. The dense forest canopy and abundant leaf litter in rainforests help retain soils, slow erosion, and continually recycle nutrients. Once trees are removed, heavy tropical rain rapidly washes away the nutrient-rich topsoil, and without diverse organic input, the soil’s fertility drops quickly. Monoculture farming of cash crops further depletes the soil because one crop repeatedly takes up the same nutrients, and there’s far less natural replenishment from varied plant and litter inputs. While pesticides, industrial waste, or fertilizers can influence soil health, they don’t capture the primary mechanism of depletion here—the disruption of the forest system and the shift to continuous monoculture.

When a rainforest is cleared and converted to a cash-crop system, the main reason soil fertility declines is the loss of protective vegetation and the move to a single-crop, high-demand land use. The dense forest canopy and abundant leaf litter in rainforests help retain soils, slow erosion, and continually recycle nutrients. Once trees are removed, heavy tropical rain rapidly washes away the nutrient-rich topsoil, and without diverse organic input, the soil’s fertility drops quickly. Monoculture farming of cash crops further depletes the soil because one crop repeatedly takes up the same nutrients, and there’s far less natural replenishment from varied plant and litter inputs. While pesticides, industrial waste, or fertilizers can influence soil health, they don’t capture the primary mechanism of depletion here—the disruption of the forest system and the shift to continuous monoculture.