Deforestation the removal of a large forest area reduces soil fertility. It’s mainly caused by human activity.When Forests are cleared, the soil loses nutrients as there is no longer a planet litter.As a result of this humus can’t be created as there’s a reduction in plant litter. The land is then exposed, heavy rainfall increases leaching, which washes away the remaining nutrients that were present. The land is then exposed to soil which degrades the sunlight,which degrades the soil make it unable to support crops.