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eelgrass beds are subtidal, and their distribution is light limited. In 

 contrast, protecting salt marshes from nutrient loading is rarely an 

 issue, because salt marsh production is enhanced by added nutrients 

 (Valiela et al . , 1975). 



Because water quality declines are often due to many sources, and 

 often difficult to quantify or assess, some managers view protection of 

 eelgrass beds from water quality declines as uneconomical or unworthy. 

 This view is short sighted, because eelgrass beds are closely linked to 

 the ecology of coastal waters. Many other species besides eelgrass are 

 also affected by water quality declines or disappearance of eelgrass. 

 Beaches and shellfish beds may be closed due to fecal coliform 

 contamination. Shellfish habitat may disappear because dense growths of 

 drift algae form an impenetrable layer preventing oxygenated water from 

 reaching the bottom (Lee and Olsen, 1985) , smothering bivalves and other 

 infauna. This dense growth may create such a high oxygen demand during 

 quiescent summer periods that anoxic events may occur resulting in fish 

 kills. Excessive algal growth sometimes release displeasing odors or 

 cover beaches, making them unaesthetic. Other synergistic effects are 

 now being realized. Algal growth, decreased water transparency, and 

 nutrient loading facilitates fecal coliform survival or even promotes 

 growth (Heufelder, 1985). 



Thus, eelgrass beds are merely one component of coastal waters 

 that are sensitive to declining water quality. In many areas, the loss 

 of eelgrass could have been used as an early warning for more damaging 

 changes that were to occur; that is, eelgrass bed declines may be used 

 as a tool for diagnosing the "health" of a bay. Protecting water 



