Fig 3. Isotopic difference between lipids or fatty acids and bulk biomass.
a) The carbon isotopic difference (Δ δ13C) between total lipids and bulk biomass is strongly correlated with the isotopic difference between biomarker fatty acids and bulk biomass for phytoplankton, bacteria and terrestrial organic matter. b) Carbon isotopic difference between total fatty acids and bulk biomass is strongly correlated with that between bulk biomass phospholipid fatty acids.