sorry, i'm a little late with this...
This article talks about the effects of years and years of war in Afghanistan, especially the civil war. It touches on a few things already mentioned by Slavi and Evelyn, in regards to deforestation and land mines, but offers some other facts as well.
here is the link: http://www.motherjones.com/environment/2002/03/afghanistans-environmental-casualties
their natural resources are depleting as a result of being over used to make war weapons, but also in order to survive financially in war times. one resource especially over used has been the forests. the lumber industry has been one of few money-making industries because wood is need to create and fuel the building of war infrastructure. much of this wood is smuggled out of the country by a timber mafia. the lack of trees leaves the earth exposed, and as the top soil erodes, the land is made unusable for agriculture.
a lot of this land is filled with left over land mines from the civil war, an estimated 10 million! that kill or injure 3 people per day!
a drought has caused even more fighting over water access of rivers and canals. also, the animal biodiversity of Afghanistan is suffering signifcantly. There are lots of problems with poaching and hunting endangered species for food and profit on the black market.
the devastation that Afghanistan has sufferd because of conflict and war is unbelievable, and there is no sign of things turning around. the land, air, and water is constantly degrading and becoming unusable, and creating an unlivable environment for humans to live.