10 100 



HUMAN POPULATION (THOUSANDS) 



1000 



Figure 46. — The relations between the human population in communities bordering estuaries and the filled area, 

 the number of pollution sources, and the area closed to shellfishing in the eight segments of coast in Figures 41-43. 

 Trend lines were computed by the method of least squares. Two segments were omitted from calculation of the 

 trend line of filled areas because they differed widely from the other six. One appears in parentheses; the other 

 fell slightly below the base line, so is not shown. 



that are producing commercially on Florida's 

 west coast is about 13,844 acres (5,603 ha); 

 170,698 acres (69,081 ha) are closed to shell- 

 fishing by public health authorities. 



13. Human population increased from 614,616 

 persons in 1930 to 3,320,226 persons in 1970 in 

 counties of Florida's Gulf coast. Dade County 

 (1,267,792 persons in 1970) is included because 

 it borders Florida Bay. 



14. The principal industries of Florida's west 

 coast in decreasing order of their economic value 

 appear to be manufacturing, tourism, construc- 

 tion, sport fishing, agriculture, phosphate mining 

 and commercial fishing. The port of Tampa 

 ranked seventh in the United States in 1968 

 based on tonnage handled, 27,436,709 short tons 

 (24,890,164 metric tons). 



15. About 43 percent of the area of Florida's 



120 



