108 



in the tropics than in Arctic, and life in tropical environments is more 

 prolific than in the Arctic. 



Although water temperatures in the estuarine zone are closely 

 related to the input of solar radiation, they are also greatly influenced 

 by the temperatures of nearby cold or warm ocean currents. Many plant 

 and animal species tolerate a wide enough temperature range to sur- 

 vive in considerable stretches of the estuarine zone from north to south. 



There are a considerable number of plants and animals that have 

 adapted to temperature ranges in the colder estuarine zone; others 

 have adapted to temperature ranges occurring in the warmer tem- 

 perate and subtropic waters of the estuarine zone ; and there are some 

 that have adapted to the colder waters of the northern estuaries, the 

 warmer waters of the southern estuarine zone, and the gradations in 

 between. Figure IV. 1.37 shows the temperature ranges tolerated by 

 some characteristic estuarine organisms. 



The quality of water in the estuarine zone has sometimes dramatic, 

 sometimes subtle, effects on estuarine life. The disolved and particulate 

 nutrients so plentiful in the coastal zone make this area very produc- 

 tive compared to other parts of man's environment. The coral reef 

 communities of the tropics, where energy conversion is primarily a 



FIGURE IV.1.37 COMMON TEMPERATURE RANGES OF OCCURENCE OF 

 SOME ESTUARINE-DEPENDENT PLANTS & ANIMALS 



Atlantic Oyster 



Striped Bass 



Chinook Salmon 



Sockeye Salmon 



California Grunion 



Turtle Grass 



Salt Marsh Grass 

 (Spartina) 



30 



40 



Temperature Range 

 (degrees F. ) 



00 60 70 80 90 



100 



Sources: Odum, H. T., op. cit. 



"Industrial Waste Guide on Thermal Pollution," 

 FWPCA, p. 40-42 (1968) 



