accumulation is little known. Information on the pathways and rates of 

 movement of these pollutants through the ecosystem also is needed. 



The relative and absolute importance of the various sources of primary 

 production in estuaries is not well understood. Information on the 

 contributions of phytoplankton, intertidal and subtidal macroalgae, benthic 

 diatoms, emergent wetlands, eelgrass beds, and river inflow would enable 

 researchers to identify the systems most in need of consideration by 

 management. Secondly, it is important to understand the ecological factors, 

 such as shelter, habitat type, and nutrient requirements, which control the 

 distribution and abundance of these plants. Using the data of the NWI , 

 researchers may now be able to quantify the production contributions of the 

 various habitat types and hence estimate the total productivity of the coastal 

 system. Eelgrass beds need investigation from the point of view of providing 

 habitat space for several groups of organisms. 



As an adjunct to the productivity research needs mentioned above, research 

 also is needed on carbon pathways through the ecosystem: the fate of 

 primary productivity needs to be known. Specific questions would involve the 

 food and feeding of the primary consumers, benthos, and zooplankton and the 

 utilization of these species by fish, birds, and marine mammals. 



Many large data gaps exist concerning the fauna of the characterization area. 

 Data are lacking on the distribution, abundance, and biomass of the subtidal 

 benthos of marine and estuarine areas. Most estuaries and much of the coast 

 have not been sampled, so no baseline exists for impact assessment. No data 

 are available on the natural variability of the fauna and no studies of the 

 secondary productivity of zooplankton or benthos have been carried out. The 

 biology of many ecologically and commercially important species is not fully 

 understood. For example, the early life histories of the bloodworm and the 

 sea scallop are not known and regulation is, therefore, difficult. Little is 

 known about the ecological factors controlling most intertidal and subtidal 

 species, and almost nothing is known about species interactions. Why such a 

 high diversity exists in the Sheepscot estuary and whether high diversity is a 

 general characteristic of the characterization area are questions that remain 

 unanswered. 



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