Which is a likely consequence of the destruction of tropical rain forests?

Which is a likely consequence of the destruction of tropical rain forests?

• A. Reduced carbon dioxide levels in regional atmospheres
• B. Increased precipitation in areas where forest cutting occurred
• C. Decreased regional surface and air temperatures
• D. Accelerated soil erosion in areas where forest cutting occurred

Answer: (D)

When tropical rainforests are destroyed, soil erosion happens more quickly. The tall trees and thick undergrowth normally shield the soil from the impact of heavy tropical rains and hold it in place with their roots. Without that protection, rainwater washes away the topsoil, nutrients are washed out, and sediment runs into nearby waterways. This loss of soil fertility and increased erosion is a direct, likely consequence of clearing forests. Other outcomes listed aren’t as plausible. Removing forests tends to release stored carbon, raising regional CO2 levels rather than reducing them, and it often lowers, not increases, local rainfall because the forest’s evapotranspiration helps drive precipitation. It also tends to raise, not lower, surface and air temperatures due to less shade and cooling from moisture loss.

When tropical rainforests are destroyed, soil erosion happens more quickly. The tall trees and thick undergrowth normally shield the soil from the impact of heavy tropical rains and hold it in place with their roots. Without that protection, rainwater washes away the topsoil, nutrients are washed out, and sediment runs into nearby waterways. This loss of soil fertility and increased erosion is a direct, likely consequence of clearing forests.

Other outcomes listed aren’t as plausible. Removing forests tends to release stored carbon, raising regional CO2 levels rather than reducing them, and it often lowers, not increases, local rainfall because the forest’s evapotranspiration helps drive precipitation. It also tends to raise, not lower, surface and air temperatures due to less shade and cooling from moisture loss.