main reasons for global warming

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1、population growth
In recent years, the increase of population is one of the main factors
that cause global warming.It seriously threatens the ecological
balance,and intensifys greenhouse effect by increase the emission of
carbon dioxide

air pollution
At present, the serious pollution of the environment has become a
major global problem, but also one of the main factors leading to
global warming. Now, the study of global climate change has clearly
pointed out that the temperature of the earth surface has begun to
rise since the end of last century..

Desertification of land
As is known to all,good vegetation can prevent water loss and soil
erosion.Up to now, human activities damage forest for wood,such as
disafforestation,land reclamation and overstocking.Soil erosion
reduces soil fertility and water retention.therefore, Wide floods and
dust storms will happen,then caused great economic losses, and the
deterioration of ecological environment.

reduction of forest resources
In the world, forest area is sharply reduced due to the natural or man-
made factors..