SUMMARY 



Characterizations integrate functionally the 

 major elements of an ecosystem. Elements include, 

 but are not limited to, physiography and geology, 

 climate, and physical transport mechanisms. Ex- 

 amples of physical transport mechanisms are 

 hydrology, sediment flux, physical oceanography 

 (in the case of marine systems), energy flows and 

 trophic relationships, and atmospheric transport. 

 Characterizations describe the important species, 

 populations, and communities in the ecosystem, 

 with particular emphasis on those organisms per- 

 ceived as being of importance (recreational or com- 

 mercial) to man or vital to the natural functioning 

 of the ecosystem being studied. Population esti- 

 mates do not require precise statistical sampling, 

 but where feasible, estimates are used to address 

 the extent and causes of natural variation. The 

 main objective of a characterization is to describe 

 socioeconomic, physical, and biological features as 

 interacting components, thereby estabhshing a 

 foundation upon which impacts of man, including 

 modifications to the ecosystem, can be predicted. 



Unlike a baseline study, many of the elements 

 described in the characterization are important, 

 not because they are expected to change as a result 

 of a proposed development, but because know- 

 ledge of these elements is needed to understand the 

 ecosystem. Characterizations should be an early 

 step in the analysis of any coastal ecosystem under 

 major study for impact analysis purposes, for activ- 

 ities such as coastal and onshore impacts from 

 OCS, for rediversion of freshwater inflows into 

 estuaries, for increased residential or commercial 

 developments in a coastal area, etc. The characteri- 

 zations will provide decisionmakers, and those ad- 

 vising decisionmakers on ecological matters, with 

 guidance tools for the planning process. Guidance 

 will be in the form of broad ecosystem understand- 

 ing and will not be impact specific. Characteriza- 

 tions should aid in assessing the effects of a variety 

 of coastal developments. The characterization ap- 

 proach has the additional benefit of pinpointing 

 data gaps, thereby identifying research priorities. 



