Monday, July 31, 2006

[80] Acid Rain


Acid rain is primarily caused by sulfur and nitrogen compounds that are released by factories, cars, and especially coal power plats. The emission can be carried hundreds of kilometers to effecting ecosystems in other countries. Acid rain has harmful effects on plants, aquatic animals, and infrastructure.

Saturday, July 8, 2006

[78] People Power





The scale of regions reflects the size of population.