Coastal ecosystems are areas where land and water join to create an environment with a distinct structure, diversity, and flow of energy. They include salt marshes, mangroves, wetlands, estuaries, and bays and are home to many different types of plants and animals. However, coastal ecosystems are also very sensitive to changes in the environment, and there is concern that some areas are now struggling to maintain their diversity due to human activity, the introduction of non-native species, and other factors.

Natural phenomenon, including hurricanes and El Niño, have been responsible for a significant amount of damage to coastal ecosystems, displacing marine and other wildlife, depleting food supplies, and disrupting the ecosystem’s balance. Hurricanes Andrew, Katrina, and Rita destroyed many acres of wetlands in the coastal regions surrounding Florida and the Gulf of Mexico ; it is not yet clear what the long-term effects of this destruction will be.

However, the most significant issue facing coastal areas is runoff from industrial, agricultural, and municipal areas, sometimes stemming far from the coastal area.

The runoff can result in higher nutrient and/or pollutant levels in coastal waters, fueling algae blooms that can be dangerous to both humans and marine life. This can be particularly concerning since coastal areas are often important fisheries. In addition to potential contamination of coastal and ocean waters, destructive fishing practices and overfishing also threaten both coastal fish populations and their habitats.

While farm-raised fish can reduce pressure on some native stocks, effluent from fish farms can contaminate the surrounding water and, if any farm fish escape, can compete with native fish and become an invasive species. Invasive species can also be introduced by many of the marine vessels that release their bilge water within coastal waters, including cruise ships. While many governments have regulations governing their own territorial waters, international treaties that attempt to govern activities, including the dumping of wastes, overexploitation of fisheries, and hunting of marine creatures such as whales, are often difficult to enforce.



The Environmental Literacy Council