230 



WOODWELL, RICH, AND HALL 



TABLE 6 



BIOMASS AND PRODUCTIVITY OF PHYTOPLANKTON* 



Region 



Locality 



1175 



249 



131 



0.5 



898 



702 



52 



55 



•Values given in g C/m 2 were multiplied by 2.5 for g (dry weight)/m 2 . 



Submerged Angiosperms 



Four reports of net production of submerged angiosperms suggest a range of 

 2200 to 4000 g nr 2 year * (Table 4). All reports are from southern latitudes. 



Epiphytic and Benthic Algae 



Net production of attached algae can probably be measured with reasonable 

 precision simply by harvest techniques, although there is always question as to 

 losses through grazing and losses of soluble compounds. The data suggest a range 

 of net production from 71 to 785 g (dry organic matter) m year . No 

 latitudinal or other trend is conspicuous (Table 5). 



Phytoplankton 



The methods used in measurement of net production of phytoplankton also 

 leave many questions as to precisely what has been measured and the magnitude 

 of errors. The range of data in Table 6 is from 131 to 1368 g (dry organic 



