The elemental stoichiometry (C, Si, N, P) of the Hebrides Shelf and its role in carbon export
| العنوان: | The elemental stoichiometry (C, Si, N, P) of the Hebrides Shelf and its role in carbon export |
|---|---|
| المؤلفون: | Susan E. Hartman, Nicola M. Clargo, Lesley Salt, Stuart C. Painter, Victoria S. Hemsley, Lucie Daniels, Chris J. Daniels, Grigorios Moschonas, Stephanie R. Allen, Yann Bozec, Keith Davidson, Caroline Kivimäe |
| المساهمون: | Station biologique de Roscoff [Roscoff] (SBR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS) |
| المصدر: | Progress in Oceanography Progress in Oceanography, 2017, 159, pp.154-177. ⟨10.1016/j.pocean.2017.10.001⟩ |
| سنة النشر: | 2017 |
| مصطلحات موضوعية: | 0106 biological sciences, 010504 meteorology & atmospheric sciences, Aquatic Science, 01 natural sciences, Nutrient, Water column, Particulate organic matter, Phytoplankton, Organic matter, 14. Life underwater, 0105 earth and related environmental sciences, Redfield ratio, chemistry.chemical_classification, 010604 marine biology & hydrobiology, Geology, 15. Life on land, Particulates, NW European shelf sea, Stoichiometry, Dissolved nutrients, Oceanography, chemistry, Productivity (ecology), [SDU]Sciences of the Universe [physics], 13. Climate action, Benthic zone |
| الوصف: | International audience; A detailed analysis of the internal stoichiometry of a temperate latitude shelf sea system is presented which reveals strong vertical and horizontal gradients in dissolved nutrient and particulate concentrations and in the elemental stoichiometry of those pools. Such gradients have implications for carbon and nutrient export from coastal waters to the open ocean. The mixed layer inorganic nutrient stoichiometry shifted from balanced N:P in winter, to elevated N:P in spring and to depleted N:P in summer, relative to the Redfield ratio. This pattern suggests increased likelihood of P limitation of fast growing phytoplankton species in spring and of N limitation of slower growing species in summer. However, as only silicate concentrations were below potentially limiting concentrations during summer and autumn the stoichiometric shifts in inorganic nutrient N:P are considered due to phytoplankton nutrient preference patterns rather than nutrient exhaustion. Elevated particulate stoichiometries corroborate non-Redfield optima underlying organic matter synthesis and nutrient uptake. Seasonal variation in the stoichiometry of the inorganic and organic nutrient pools has the potential to influence the efficiency of nutrient export. In summer, when organic nutrient concentrations were at their highest and inorganic nutrient concentrations were at their lowest, the organic nutrient pool was comparatively C poor whilst the inorganic nutrient pool was comparatively C rich. The cross-shelf export of these pools at this time would be associated with different efficiencies regardless of the total magnitude of exchange. In autumn the elemental stoichiometries increased with depth in all pools revealing widespread carbon enrichment of shelf bottom waters with P more intensely recycled than N, N more intensely recycled than C, and Si weakly remineralized relative to C. Offshelf carbon fluxes were most efficient via the inorganic nutrient pool, intermediate for the organic nutrient pool and least efficient for the particulate pool. N loss from the shelf however was most efficient via the dissolved organic nutrient pool. Mass balance calculations suggest that 28% of PO43-, 34% of NO3- and 73% of Si drawdown from the mixed layer fails to reappear in the benthic water column thereby indicating the proportion of the nutrient pools that must be resupplied from the ocean each year to maintain shelf wide productivity. Loss to the neighbouring ocean, the sediments, transference to the dissolved organic nutrient pool and higher trophic levels are considered the most likely fate for these missing nutrients. |
| وصف الملف: | application/pdf; text |
| اللغة: | English |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::de9ef5fbcb1fa961ccfd4605f62d2915 http://www.vliz.be/imisdocs/publications/24/310224.pdf |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....de9ef5fbcb1fa961ccfd4605f62d2915 |
| قاعدة البيانات: | OpenAIRE |
| الوصف غير متاح. |