Carbon isotope fractionation from organism growth

Figure U. Theoretical models for carbon isotope fractionation between diet and bone in humans. Top, isotopic fractionation resulting from organism growth (major pathway emphasized) and bottom, isotopic fractionation resulting from energy metabolism (major pathways emphasized).

Figure 2. Chemostat experimental results representing controls on the isotopic fractionation by marine algae, (a) Plot of isotopic fractionation (Cp) as a function of growth rate (p) divided by the concentration of dissolved CO2 for selected marine organisms, (b) Plot of the slopes of the relationships represented in (2a) as a function of the ratio of cellular carbon to cell surface area. Dashed lines represent relationships estimated from other studies, (c) Plot of the slopes from (2a) as a function of observed cell volume to smface area ratios, (d) Plot of isotopic fractionation (Cp) as a function of the product of the growth rate divided by CO2 concentrations and the volmne-to-smface area ratios for the eukaryotic species in (2a). [Used by permission of the editor of Geochimica et Cosmochimica Acta, from Popp et al., (1998), Figirre 2]...

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