| Size fractionation 14C02 experiments were used to investigate the pathways of carbon assimilation in the small ( <: 1 J.lm) fraction of natural plankton populations. Label distribution among the fractions provided evidence for the transfer of recently incorporated labeled carbon from "phytoplankton" to "bacterial" fractions. In the < 1 J.liD fraction, both photosynthetic C02 assimilation and heterotrophic assimilation of labeled exudates contributed significantly to carbon assimilation, comprising up to 18 and 33 % of the who le sample assimilation, respectively. |
