Dear List,

We run many samples of plant and animal tissue from freshwaters that are
high in carbonates.  We're interested in finding a way to remove carbonates
before analysis so that we just get the organic carbon for d13C
measurements.  I've heard of washing with dilute acid or even just water,
but have also heard of shifts in d15N and d13C (of the organic matter) that
can result from such treatment.

Is there any consensus on the best way to remove carbonates from such
samples without biasing either the d13C or d15N readings of the organic
matter in the sample?  Any experiences out there with good or bad
approaches?

Thanks for your input.

Bruce Hungate



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Bruce Hungate
Assistant Professor
Dept. of Biological Sciences
Box 5640
Northern Arizona University
Flagstaff AZ 86011-5640

phone:  520 523 0925
fax:    520 523 7500
email:  [log in to unmask]
http://www2.nau.edu/~bah/

Stable Isotope Lab
http://www2.nau.edu/~bah/cpsil.html
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