Stable carbon and nitrogen isotope ratios of penaeid juveniles and primary producers in a riverine mangrove in Guimaras, Philippines
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Stable carbon and nitrogen isotope ratios were analyzed for primary producers and juveniles of four penaeid species (Metapenaeus ensis, Penaeus indicus, P. merquiensi and P. monodon) in a riverine mangrove in Guimaras, central Philippines. δ13C values of shrimp (- 15.5 to - 19.6‰) were closer to phytoplankton (-23.8‰) and possibly epiphytic algae (-24.2‰) than to mangrove leaves (-26.9 to -30.0‰) or detritus (-28.0‰). Differences in δ15N values suggested 2-3 trophic shifts between phytoplankton (0.6‰) and shrimp (6.9‰), assuming a 2.4‰ enrichment per trophic level. There were no significant differences in δ13C and δ15N ratios between green and decomposing leaves, and among mangrove species, shrimp species and different size groups of shrimp.
CitationPrimavera, J. Honculada. (1996). Stable carbon and nitrogen isotope ratios of penaeid juveniles and primary producers in a riverine mangrove in Guimaras, Philippines.
PublisherUniversity of Miami, Rosenstiel School of Marine and Atmospheric Science
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ArticleS Watanabe, M Kodama, JG Sumbing & MJH Lebata-Ramos -
Japan Agricultural Research Quarterly, 2013 - Japan International Research Center for Agricultural Sciences (JIRCAS)To provide a basis for a stable carbon and nitrogen isotope ratio (δ13C / δ15N) analysis to determine the assimilated organic matter in sea cucumber, Holothuria scabra, diet-tissue fractionations were experimentally determined by mono-feeding rearing with diatom. While δ15N fractionation of the whole body wall (2.4‰) was similar to the commonly accepted value (2.6 - 4‰), δ13C fractionation of the body wall (4.2‰) showed considerable discrepancy with the commonly accepted value (0 - 1‰) due to the high content (35% dry wt/wt) of calcareous spicules (CaCO3) in the body wall, which had significantly higher δ13C (-8.6‰) than the organic fractions. Computational elimination of spicules based upon spicule content and spicule δ13C reduced the δ13C fractionation of the body wall to 1.5‰, close to the common value. δ13C fractionation after spicule removal by acid decarbonation and subsequent rinsing (3.2‰) did not agree with the common value, and δ15N fractionation was significantly elevated by decarbonation. δ15N and δ13C fractionations of the intestine (1.5 and 2.2‰, respectively) did not agree with the common values. Since δ13C and δ15N of the feces did not differ significantly from those of the diet, feces may be used to determine ingested organic matter in the wild.
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