Human activities have converted forest land into non-forest use, forestland to farms, ranches or urban use. The negative effects of deforestation include the following;
Encouraging soil erosion
When forests are cleared, soil cover which consists mainly of vegetation is removed as well and this exposes the bare soil to extreme conditions produced by the sun’s heat and rainwater resulting in soil erosion.
Destruction of watersheds areas resulting in flooding
Deforestation can result to watersheds that are no longer able to sustain and regulate water flows from rivers and streams. Trees are highly effective in absorbing water quantities, keeping the amount of water in watersheds to a manageable level. The forest also serves as a cover against erosion. Once they are cut down, too much water ran downstream causing flooding and disasters. Landslides are now becoming common.
The deforested areas loose soil fertility
Most of the areas that have undergone deforestation are actually unsuitable for long term agricultural use such as ranching and farming. Once deprived of their forest cover, the lands rapidly degrade in quality, losing their fertility and arability.
The local people are displaced.
When governments decide to offer forests for deforestation mainly to open up areas for commercial activities, indigenous peoples are hardly included in economic and political decisions that directly affect their lives.
Loss in the number of biodiversity.
This is probably the most serious consequence of deforestation which means the destruction and extinction of many plants and animal species, many of whom remain unknown and whose benefits will be left undiscovered.
Climate change
Forest soils are moist, but without protection from sun-blocking tree cover they quickly dry out. Trees also help perpetuate the water cycle by returning water vapor back into the atmosphere. Without trees to fill these roles, many former forest lands can quickly become barren deserts.
Greenhouse Effect
Trees also play a critical role in absorbing the greenhouse gases that fuel global warming. Fewer forests means larger amounts of greenhouse gases entering the atmosphere and increased speed and severity of global warming.
Water cycle is also affected by deforestation
Trees extract groundwater through their roots and release it into the atmosphere. When part of a forest is removed, the trees no longer evaporate away this water, resulting in a much drier climate.