Nitrogen stable isotopes in the shell of Mercenaria mercenaria trace wastewater inputs from watersheds to estuarine ecosystems

Nitrogen isotopes in otoliths reconstruct ancient trophic position

“…To our knowledge, only one ecological study has compared tissue and otolith aragonite δ 15 N values, and they also found otoliths to be on average slightly lighter than muscle tissue of fish (Vandermyde and Whitledge 2008). Vandermyde and Whitledge (2008) (Carmichael et al 2008;Delong and Thorp 2009). Our muscle tissue to otolith δ 15 N comparisons support others findings that there is a slight depletion in 15 N between the biogenic aragonite and soft tissue within an organism.…”

Carbon Stable Isotope Values in Plankton and Mussels Reflect Changes in Carbonate Chemistry Associated with Nutrient Enhanced Net Production

“…Because production and respiration dynamics are not uniformly distributed through a system in either time or space our sensor technology may not capture all sensitive areas. We suggest that δ 13 C values measured in shellfish will provide a good proxy for production history, integrated over the tissue turnover time of the organism, which is on the order of weeks, or even less (e.g., Hawkins, 1985;Carmichael et al, 2008).…”

Analysis of δ15N values in mollusk shell organic matrix by elemental analysis/isotope ratio mass spectrometry without acidification: an evaluation and effects of long‐term preservation

“…While we cannot prove either process caused the shift, we suggest that the ethanol-preserved shells are altered and the dry-stored shells are not. We hypothesize that the soft tissues, with abundant N, leached 14 N into the ethanol solution (the ethanol residue was about 0.4% lighter than the tissues; Fig. 3), which was then taken up into the shell shells soaking in this solution for more than 70 years.…”

“…Therefore, samples are generally treated with an HCl solution before analysis. [13,14,20,21] However, the acidification process in itself may influence d…”

“…Prior acidification is not required to eliminate the carbonate matrix to produce accurate results, as has been previously reported. [14] It should be noted that mollusks with very low organic matrix in their shells may require a pre-concentration step to reduce the poorer precision of small samples. However, considering the large fractionations associated with nitrogen isotopes in nature, even samples between 5 and 15 mg N provided reasonable data (1s ¼ 0.36).…”