1 / 24

Why Spring ?

Why Spring ?. It is the first important biological event after shipwreck Bloom of phytoplankton in the area Spawning of many species of fishes and shellfish of commercial interest Effects on plankton ---- effects on food web. Source of Data.

sora
Download Presentation

Why Spring ?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Why Spring ? • It is the first important biological event after shipwreck • Bloom of phytoplankton in the area • Spawning of many species of fishes and shellfish of commercial interest • Effects on plankton ---- effects on food web

  2. Source of Data • Instituto Español de Oceanografia Core Project: Studies on Times Series of Oceanographic Data • Starting in 1988 in A Coruna • Several localities of study in the N-NW Coast of Spain • Pelacus Cruises • Cover the area from Portugal to France • OmexII Satellite Data • For the area in front of Rias Bajas • Satellite chlorophyll IEO • Gijon Radial

  3. Area of study WBB NG EBB SG

  4. Have effects on phytoplankton been observed after the Prestige oil spill during spring? • Effects on biomass (chlorophyll-a) • Effects on physiology (primary production) • Effects of taxonomic groups • Effects on main phytoplankton species

  5. Effects on biomass (chlorophyll-a)

  6. Effects on biomass (chlorophyll-a)

  7. Effects on primary production

  8. Effects on primary production

  9. Effects on diatoms

  10. Effects on diatoms

  11. Effects on dinoflagellates

  12. Effects on dinoflagellates

  13. Main phytoplankton species

  14. Effects on biomass during Pelacus Cruises Bf: 1999-2002 Af: 2003

  15. Effects on primary production OMEX II Box Area

  16. Radial Gijon. Instituto Español de Oceanografia

  17. Final Remarks No effects on phytoplankton at several levels Differences are the result of natural variabiliy of ecosystem

  18. Why effects have not been observed?

  19. Low solubility of Prestige fuel Low concetrations in water Low concentations in plankton Low aromatic content High density--sinking Pristane/Phytane ratio no Prestige

  20. Plankton mechanisms remove oil from surface waters Zooplankton: grazing on oil particles Fecal pellets sinking to bottom Diatoms: adsorption on silica wall eventual sinking to bottom Detritus and clay particles: adsorption Aggregates and eventual sinking

  21. A Coruna Zooplankton: oil in the gut content

  22. CONCLUSIONS • No effects have been observed on phytoplankton during spring blooms for biomass, production and community structure • We can not ascertain whether or not oil has affected phytoplankton • Large variability caused by meso and large-scale processes masks any effect • Effects reduced or short-lived. No effect on spring bloom

  23. Acknowledgements • Technical assistance • Teodoro Patrocinio Ibarrola • Jorge Lorenzo Salamanca • Leticia Viesca Lombardia • Crew of R/V • IEO (Lura, Rioja, Navaz) • IFREMER (Thalassa) • Projects • CICYT Aes: Reconocimiento Oceanografico en la época de floración primaveral en Galicia y Cantábrico • IEO: Studies on Time Series of Oceanographic Data • EU: Pelasses and Sardyn

More Related