Question

why deforestation??

Answer 1

only due to humans who cut trees for there betterment

Answer 2

Deforestation is the removal of a forest or stand of trees where the land is thereafter converted to a nonforest use.

Destruction of carbon sinks:
Carbon sinks are huge stores of carbon, e.g. Swamps and forests
•Soil Erosion:
Deforestation makes soil prone to erosion by agents such as wind and water. The roots of trees hold the particles of soil together thus, preventing the fertile top soil from being carried away. Soil erosion leads to loss of productivity of the land due to loss of mineral nutrients and soil microorganisms
•Destruction of animal habitats:
Apart from domesticated animals and marine and fresh water animals, all other animals need forests as their habitats. These forests do not only provide a place for the animals to roam day but also provide their food and act as a source of protection from predators through camouflage. Destruction of the animals’ habitats literally kills the animals.
•Medicinal Plants:
Some trees are used as herbs. Trees such as the Cinchona have been used as treatment against Malaria since time immemorial. Destruction of these forests leads to destruction of medicinal plants that could be used as treatment for various ailments.
•Trees act as windbreakers:
Absence of these trees enables strong winds and or storms e.g. Hurricanes and Tornados. I write this in the wake of a Tsunami at the Indonesian coast where about 150 people have just lost their lives. Hurricanes like Katrina are still fresh in our memories. I cannot over emphasize this point.
•Greenhouse effect and global warming:
Nature balances the flow of energy and nutrients. Forests plan a very vital role in these cycles e.g. the carbon cycle where deforestation causes carbon dioxide to remain in the atmosphere. Accumulation of carbon dioxide in the atmosphere acts as a blanket that traps long wave radiation of heat and prevents it from escaping the surface of the earth back into the atmosphere. This phenomenon is known as the greenhouse effect. The trapped radiation is converted into heat. This heat causes global warming.
Destruction of forests also causes modification of climate of an area mostly leading to desertification and aridity.
Hope this helps you