Unformatted text preview: PROBLEM
• The Chesapeake Bay is currently experiencing one of its worst oxygen deprived “dead zones,” since 1998. In recently released data from a report by the Chesapeake Bay Program studies show that ten percent of the bay’s main stem is anoxic. Researchers working with the Chesapeake Bay Program say they aren’t surprised by the results. In fact, a local analyst, Dave Jasinski, working for the University of Maryland Center for Environmental Science predicted that this summer’s dead zone would be the fourth worst in 20 years. The oxygen contained in the Chesapeake Bay’s waters is its lifeblood. The oxygen contained in the bay is vital to the survival of the many organisms, sea creatures, and plants that the bay shelters. What is a “dead zone”?
What is a “dead zone”?
• A dead zone is a large area of oxygendepleted water. It is especially hard for plants and animals to survive in a dead zone. Fish and plants in the bay need oxygen to survive just like land animals and plants. The water in the Chesapeake Bay is partly composed of oxygen. The plants and fish that live in the bay take their oxygen from the water in the bay. If the amount of oxygen in the water is low, the organisms that need the oxygen will struggle to survive. Ten percent of the Bay’s main stem is considered anoxic, meaning it contains little oxygen. This percentage of the bay contains less than 0.2 milligrams of oxygen per liter, making it nearly impossible for fish and crabs to survive. Dead zones generally develop in quiet, deep waters a few kilometers offshore. Marine ecologists have documented cases of both large and small dead zones throughout U.S. coastal waters over the past decade. CAUSES
• Dead Zones in the Chesapeake Bay are caused by low oxygen levels. Low oxygen levels in the Chesapeake Bay are caused by many factors. Some of the factors include pollution, climate changes, sedimentation, as well as high and low precipitation rates. Similar situations to that of the Bay’s are being experienced in a worldwide plague of dead zones along coasts near the equator. Coastal dead zones are caused almost exclusively by human activity. EFFECTS
• Death of marine plants and animals
Chesapeake Bay’s health deteriorates
Crabs, oysters, and rockfish die off
Oxygen starved crabs crawl out of water to land in search of oxygen SOLUTIONS
• There is a variety of possible solutions to the current dead zone problem in the Chesapeake Bay. Local politicians have a key role in finding a solution to the dead zone problem. The President of the Chesapeake Bay Foundation, William C. Baker, says that politicians need to be pressured to pass laws to reduce levels of nutrients such as nitrogen and phosphorus, including pollution restrictions for power plants and tougher emissions guidelines for motor vehicles. To reduce the amount of sedimentation, more forested buffers could be planted, and sewage treatment plants should become more modernized. The water quality of the Chesapeake Bay will only improve once the amount of nutrients and sediments flowing into the bay are decreased. PHOTOGRAPHY
PHOTOGRAPHY This map depicts 20,700 square kilometers of the dead zone in the 2001 Gulf of Mexico. MORE PHOTOGRAPHY
MORE PHOTOGRAPHY ...
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- Spring '08
- Biology, dead zones