Dataset Information

Chemosymbiotic bivalves contribute to the nitrogen budget of seagrass ecosystems.

ABSTRACT: In many seagrass sediments, lucinid bivalves and their sulfur-oxidizing symbionts are thought to underpin key ecosystem functions, but little is known about their role in nutrient cycles, particularly nitrogen. We used natural stable isotopes, elemental analyses, and stable isotope probing to study the ecological stoichiometry of a lucinid symbiosis in spring and fall. Chemoautotrophy appeared to dominate in fall, when chemoautotrophic carbon fixation rates were up to one order of magnitude higher as compared with the spring, suggesting a flexible nutritional mutualism. In fall, an isotope pool dilution experiment revealed carbon limitation of the symbiosis and ammonium excretion rates up to tenfold higher compared with fluxes reported for nonsymbiotic marine bivalves. These results provide evidence that lucinid bivalves can contribute substantial amounts of ammonium to the ecosystem. Given the preference of seagrasses for this nitrogen source, lucinid bivalves' contribution may boost productivity of these important blue carbon ecosystems.

SUBMITTER: Cardini U

PROVIDER: S-EPMC6863832 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Chemosymbiotic bivalves contribute to the nitrogen budget of seagrass ecosystems.

Cardini Ulisse U Bartoli Marco M Lücker Sebastian S Mooshammer Maria M Polzin Julia J Lee Raymond W RW Micić Vesna V Hofmann Thilo T Weber Miriam M Petersen Jillian M JM

The ISME journal 20190808 12

In many seagrass sediments, lucinid bivalves and their sulfur-oxidizing symbionts are thought to underpin key ecosystem functions, but little is known about their role in nutrient cycles, particularly nitrogen. We used natural stable isotopes, elemental analyses, and stable isotope probing to study the ecological stoichiometry of a lucinid symbiosis in spring and fall. Chemoautotrophy appeared to dominate in fall, when chemoautotrophic carbon fixation rates were up to one order of magnitude high ...[more]

PMID: 31395953

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Dataset Information

Chemosymbiotic bivalves contribute to the nitrogen budget of seagrass ecosystems.

Publications

Chemosymbiotic bivalves contribute to the nitrogen budget of seagrass ecosystems.

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