They tend to modulate sharp influences such as nutrient pulses, floods, etc. The nearshore waters of the Baltic and Great Lakes have all been degraded in part, but especially those near industrialized urban centers. Efforts toward rehabilitation of such ecological slums and toward preservation of relatively pristine heritage areas are now getting underway, if only slowly. Recent studies are described for the purposed of comparison and illustration. 9828 czmt no charge for single copies.
Wetlands perform many valuable functions.
Coastal wetlands, both freshwater and saltwater, control floods, filter pollution in river water and groundwater, provide a buffer from ocean storms, and serve as habitat for a variety of plants and wildlife, including many endangered species. Different types of wetlands can have different functions. Some isolated wetlands function as groundwater recharge areas, providing clean drinking water. Many freshwater wetlands are forested, and are used for timber productions. Only Alaska and Louisiana have higher percentages of wetlands.