Dear isotopers,
My question is the following : can we consider that the carbon isotope
composition of soil water dissolved inorganic carbon (DIC) is mainly
controlled by the average d13C value of the vegetation ? If not, what are
the other sources controlling the d13C of dissolved inorganic carbon in
soil water. I guess that soil pH, chemistry, as well as microbial activity
must have their importance.
Does anyone on the list knows about published or unpublished data with d13C
values in soil water or surface waters (rivers, lakes) DIC and co-existing
vegetation, especially in regions where C3 and C4 biomass are available. I
am working in the lake Chad basin and was not able to find any reference
reporting on this.

Many thanks in advance for your help!

Antoine