G 



PHOTOSYNTHESIS IN NATURE 



CHAP. I 



Table l.I 

 Carbon Fixation by Land Plants (after Schroeder 1919) 



suspected that it too, is relatively small. Later (1919-), he conceded 

 that the carbon fixation by the plankton may as much as double the yield 

 calculated for the land plants alone, thus bringing the annual rate of 

 carbon fixation by all plants to 3.8 X 10^*^ tons. 



It seems that Schroeder's plankton correction still was much too small. 

 Recent experiments make it probable that the oceans account for much 

 more than one-half the total organic synthesis on earth. Table l.II, 



Table l.II 

 Carbon Dioxide Reduction by the Plankton (from Riley) 



compiled b}^ Riley (1941) shows that the production of organic matter by 

 the plankton does not change much from the Equator to the Polar Circle; 

 and that the average of all measurements is as high as 375 g. of organic 

 carbon annually per sc}. meter', corresponding to 3.75 tons per hectare. 

 If this yield of organic carbon is taken as representative of all oceans, 



