Watersheds

Watersheds are the systems that hold the planet's water. Tiny streams and ponds represent local watershed, each of which feeds the larger watersheds of rivers and oceans. Dobson and Gilpin Beck elucidate the elements of a wetland ecosystem and the purification of water through it. They also examine the impact of industrial contaminants, dams, and exotic species on the overall quality of our water supply and make suggestions for reducing the toll of such pollutants.