How have humans polluted the planet?
What causes air pollution?
How is air pollution related to climate change?
What other problems does air pollution cause?
How can land pollution affect lakes and streams?
What do we do with fresh water?
How can pollution affect animals and plants?
What are we doing about pollution?
What more can we do to reduce pollution?
Can we clean up polluted areas?
Can we protect wild habitats from pollution?
How can we protect individual species?