Dear Kazushi Takahashi,

some useful references for trapping of CO2 from soils for isotope 
ratio measurements are:

J. I. Freijer; W. Bouten (1991) A comparison of field methods for 
measuring soil carbon dioxide evolution: experiments and simulation.
Plant and Soil, vol. 135, pp. 133 - 142.

G. R. Davidson (1995) The stable isotopic composition and measurement 
of carbon in soil CO2. Geochim. Cosmochim. Acta, vol. 59 no. 12, pp. 
2485 - 2489.

P. Fritz; A. A. Mozeto; E. J. Reardon (1985) Practical considerations 
on carbon isotope studies on soil carbon dioxide. Chem. Geol., vol. 
58, pp. 89 - 95.

T. E. Cerling; D. K. Solomon; J. Quade; J. R. Bowman (1991) On the 
isotopic composition of carbon in soil carbon dioxide. Geochim. 
Cosmochim. Acta, vol. 55, pp. 3403 - 3405.

Some of these deal with trapping of CO2 emitted from soils, others 
with measurement of within-soil CO2. Freijer & Bouten (1991) is not 
about isotope ratio but exact concentration measurements. It 
gives a good overview and comparison of several methods for trapping 
emitted CO2 quantitatively.

Frank Pawellek








----------------------------
Frank Pawellek
Stable Isotope Laboratory
Department of Geography
University of Wales, Swansea
Singleton Park
Swansea SA2 8PP
Wales / GB

Tel. +44 1792 295148
Fax. +44 1792 205556
email [log in to unmask]
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