II-5 



and through their nutrients, which govern the nature 

 and productivity of offshore and estuarine fisheries. 

 The cold Labrador Current water from Maine to Virginia, 

 warm Gulf Stream water along the South Atlantic and Gulf 

 coasts, and the California Current along the Pacific 

 coast all have noticeable effects on coastal land and 

 water (Figure IV.1.1). 



(3) Coastline Slope . The configuration of the coastline 

 itself, even though subject to additional molding by the 

 flow of rivers to the sea, is closely related to the 

 shape and structure of the continental shelf. A wide 

 continental shelf is generally associated with lowland 

 next to the coast, while a narrow shelf is associated with 

 mountainous terrain. These associations throughout the 

 estuarine zone of the United States have produced estuarine 

 systems characteristic of particular regions. Glaciation 

 in New England, Washington, and Alaska; old mountain 

 ranges and a sedimentary coastal plain from New Jersey to 

 Texas; and the young, steep ranges of the Pacific coast 

 are all continental features having different impacts on 

 the estuarine zone. 



(4) River Flow . The estuarine zone is also shaped through 

 erosion and sediment transport by fresh water making its 

 way to the sea. All along the coastlines are streams and 



