Dear Cecily,

I know of the following papers that touch your area of interest at
least a bit (I think):

France, R. (1998) Estimating the assimilation of mangrove detritus by
fiddler crabs in Laguna Joyuda, Puerto Rico, using dual stable
isotopes. J. Trop. Ecol., 14(4): 413 - 425.

Loneragan, NR; Bunn, SE; Kellaway, DM (1997) Are mangroves and
seagrasses sources of organic carbon for penaeid prawns in a tropical
Australian estuary? A multiple stable-isotope study. Mar. Biol.
130(2):  289-300.

Miyajima, T; Wada, E; Hanba, YT et al. (1997) Anaerobic
mineralization of indigenous organic matters and methanogenesis in
tropical wetland soils. Geochim. Cosmochim. Acta, 61(17): 3739-3751.

Bunn, SE; Davies, PM; Kellaway, DM (1997) Contributions of sugar cane
and invasive pasture grass to the aquatic food web of a tropical
lowland stream. Mar. Freshwater Res. 48(2): 173-179 1997

Cifuentes, LA; Coffin, RB; Solorzano, L et al. (1996) Isotopic and
elemental variations of carbon and nitrogen in a mangrove estuary.
Estuar. Coast Shelf Sc.43(6): 781-800.

Hemminga, MA; Mateo, MA (1996) Stable carbon isotopes in seagrasses:
Variability in ratios and use in ecological studies. Mar.
Ecol-Prog. Ser. 140(1-3): 285-298.

Hecky, RE; Hesslein, RH (1995) Contributions of benthic algae to lake
food webs as revealed by stable isotope analysis. J. N. Am.
Benthol. Soc. 14(4): 631-653.

Parsons, TR; Chen, YLL. (1995) The comparative ecology of a
sub-arctic and tropical estuarine ecosystem as measured with carbon
and nitrogen isotopes. Shelf Sc. 41(2): 215-224.


I hope this helps a bit.

Frank Pawellek
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Frank Pawellek
Institut fuer Geologie
Lehrstuhl fuer Sediment- und Isotopengeologie
Ruhr-Universitaet Bochum
Universitaetsstrasse 150
44801 Bochum
Germany
Phone: +49-234-700-5458
Fax: +49-234-7094-571
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