20 



2500 



2000 • 



1500 - 



1000 - 



500 



FRESHWATER 

 WETLAND 



WARM 

 TEMPERATE 

 MIXED 

 FOREST 



CULTIVATED 

 LAND 



GRASSLAND 



NET PRIMARY PRODUCTIVITY OF SELECTED ECOSYSTEMS [g/m2/year] 



ADAPTED FROM LIETH (1975) AND TEAL AND TEAL (1969) 



Fig. 18. Relative productivity of wetland ecosystems in relation to others (from Newton 1981). 



Fig. 19. Simplified food pathways from estuarine wetland vegetation to commercial and recreational fishes. 



