Compound-specific δ15N amino acid measurements in littoral mussels in the California upwelling ecosystem: a new approach to generating baseline δ15N Isoscapes for coastal ecosystems.

ABSTRACT: We explored δ(15)N compound-specific amino acid isotope data (CSI-AA) in filter-feeding intertidal mussels (Mytilus californianus) as a new approach to construct integrated isoscapes of coastal primary production. We examined spatial δ(15)N gradients in the California Upwelling Ecosystem (CUE), determining bulk δ(15)N values of mussel tissue from 28 sites between Port Orford, Oregon and La Jolla, California, and applying CSI-AA at selected sites to decouple trophic effects from isotopic values at the base of the food web. Bulk δ(15)N values showed a strong linear trend with latitude, increasing from North to South (from ∼ 7‰ to ∼ 12‰, R(2) = 0.759). In contrast, CSI-AA trophic position estimates showed no correlation with latitude. The δ(15)N trend is therefore most consistent with a basel

SUBMITTER: Vokhshoori NL 

PROVIDER: S-EPMC4041574 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature