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(Pearse and Muscatine, 1971; Adey, 1978). Turbidity greatly inhibits this 

 process (Loya, 1976). Furthermore, zooxanthellae may leave corals when 

 light, temperature, or other conditions are not suitable for them (Lang, 

 1971). 



To survive, organisms must be able to tolerate or avoid unfavorable 

 conditions. Frequency, amplitude, and regularity (predictability) of 

 fluctuations influence the types of sedentary organisms (e.g., vascular 

 plants, oysters and clams), as well as the ability of vagile organisms 

 (e.g., crabs, fish, and shrimp) to use these habitats. Temporal variation 

 in the coastal environment is most often caused by tides, storms, and 

 seasons. Few species are able to withstand the simultaneous fluctuations 

 in salinity, oxygen, and temperature that occur in many estuaries (Deaton 

 and Greenberg, 1986) , though those few that are well -adapted may be able to 

 be very productive because of energy subsidies. Rapid changes in 

 environmental conditions, however, can prevent the full development of an 

 ecosystem. If conditions continually change before any one group of 

 organisms becomes established, then ecological production may be restrained 

 (Montague et al . , unpublished manuscript). 



Although rising sea level will cause a succession of ecosystems, the 

 rate of rise is probably not rapid enough to prevent full ecosystem 

 development in coastal zones. The seeds and larvae of plants and animals 

 that occur at different points along environmental gradients are widely 

 distributed in estuarine waters. Marshes can become established within one 

 to five years following a sudden appearance of a favorable environment 

 (Montague, unpubl. data). Mangroves may take at most 15 to 25 years to 

 become fully developed (Odum et al., 1982). The rate of sea level rise may 

 or may not be gradual enough to create a significant long-term lag time in 

 the development of successive ecosystems. 



Despite the possibility of a timely replacement of coastal ecosystems, 

 whenever a large mass of existing organisms dies, short-term perturbations 

 may accompany the transition to a new ecosystem. Dead plant matter, for 

 example, may temporarily increase in coastal waters and sediment, formerly 

 held in place by roots and rhizomes, may become unstable (Montague, 1986). 

 The added dead matter will decompose, and so may reduce dissolved oxygen 

 levels sufficiently to cause local fish kills. Destabilized sediment will 



