1970 Volume 83 Issue 990 Pages 397-410
The dark fixation of CO2 in lakes with different trophic types was investigated. Non-photosynthetic CO2 assimilation by phytoplankton was negligibly small compared with photosynthetic assimilation. High activities of dark fixation of CO2 were observed in meromictic lakes and stagnant waters, where the dark CO2 fixation occupied 10-40% of total photosynthetic production. This can be attributed to the bacterial biosynthetic action. An importance of the dark fixation of CO2 in trophic dynamics was discussed.