Determination of precise nitrogen stable isotopic baselines from heterotrophic organism in coastal ocean environments using compound specific isotope analysis of amino acids

Choi, Bohyung; Shin, Kyung-Hoon

Determination of precise nitrogen stable isotopic baselines from heterotrophic organism in coastal ocean environments using compound specific isotope analysis of amino acids

2021

Choi, Bohyung | Shin, Kyung-Hoon

We sampled mussels (Mytilus edulis) along the coast of the Korean peninsula, and determined their trophic position (TP) using the nitrogen isotope ratio of amino acids (TPgₗᵤ/ₚₕₑ). The TPgₗᵤ/ₚₕₑ of mussels (2.0 to 2.5) is higher than TP of herbivores, suggesting that TP normalization is required to remove the trophic enrichment effect on basal nitrogen isotope ratio. We found similar trends in spatial variation between nitrogen isotopic baseline based on nitrogen isotope ratio of bulk tissue (δ¹⁵Nbₐₛₑ₋bᵤₗₖ) and that of phenylalanine (δ¹⁵Nbₐₛₑ₋ₚₕₑ) in mussels, reflecting different nitrogen sources among sampling sites. The present study suggests that δ¹⁵Nbₐₛₑ₋bᵤₗₖ and δ¹⁵Nbₐₛₑ₋ₚₕₑ are powerful tools to trace nitrogen isotopic baselines from primary consumers as well as higher TP organisms.

Afficher plus [+]