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Although literature synthesis and exploratory models will facilitate 

 the identification of specific research needs, the most relevant research 

 will undoubtedly include several general areas. The time required for full 

 development of subtidal, intertidal , and very nearshore supratidal 

 ecosystems should be established with greater certainty. Under the most 

 rapid sea level rise scenarios, conditions may not remain constant long 

 enough for full development of an ecosystem. If so, the production of fish 

 and shellfish and the stability of shorelines may decline. 



Knowledge of nearshore topography and predictions of tidal range are 

 essential to predictions of aerial extent, but so too is an understanding 

 of the level of suspended sediments to be expected and the trapping rate of 

 sediment by subtidal and intertidal plants and microbes (Montague, 1986). 



Knowledge of the major regulators of the production of principal 

 animals and plants is essential for coupling predictions of ecological 

 changes to predictions of physical changes. Factors that determine the 

 type and productivities of organisms in the coastal zone include: light 

 (turbidity), temperature, nutrients (including CO2) , salinity, water level, 

 and biochemical oxygen demand (BOD) . All of these will be influenced by 

 sea level rise, global warming, and increased levels of atmospheric CO2 . 



Physical uprooting and erosion of present ecosystems should be a major 

 agent of ecological change. Predictions are needed both for shores and for 

 tidal creeks. Knowledge of the resistance to erosion of these systems is 

 also required. 



Although human values of coastal ecosystems may be compared using 

 various energy and economic analyses, the variation in value within a 

 general category must also be evaluated. Intertidal marshes and mangroves, 

 for example, have been highly touted as good habitat for the growth of 

 juvenile fish and shellfish of commercial and recreational importance. In 

 addition, exchange of materials between the marsh and the estuary is 

 believed to control supplies of nutrients in adjacent estuarine waters. 

 Not all marshes are equivalent in their habitat value, however, and not all 

 exchange significant quantities of materials with surrounding waters 

 (Montague et al . , 1987). Perhaps the most important factor in the 

 accessibility of marshes to organisms, and in the exchange of materials, is 

 the density of tidal creeks (Zale et al., 1987). The density of tidal 



