CARBON IN THE BIOTA 



289 



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PACIFIC OCEAN 



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TROPIC OF CAPRICORN 



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 OCEAN 



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UNC BIOSPHERE MODEL: H. LIETH 



"MIAMI" MODEL: Elgene Box, H. Lieth, T. Wolaver 



Fig. 3 Productivity of the land surface of the earth, as predicted from the 

 relations shown in Figs. 1 and 2. 34 



productivity supported by the remaining low nutrient levels, and turbulent and 

 other return from deeper waters, is mostly in the range of 20 to 100 g C m -2 

 year . This range is about one-tenth that of typical, nondesert terrestrial 

 communities. If one asks a key reason why a forest should have a production 

 10 times that of a plankton community, it may be the same as the reason the 

 forest may have a biomass 10 thousand times that of the phytoplankton: 

 stability of surface. The forest occupies a fixed surface on which it can develop a 



