Details

Autor(en) / Beteiligte

• Bermejo, Paula
• Helbling, E. Walter
• Durán-Romero, Cristina
• Cabrerizo, Marco J.
• Villafañe, Virginia E.

Titel

Abiotic control of phytoplankton blooms in temperate coastal marine ecosystems: A case study in the South Atlantic Ocean

Ist Teil von

• The Science of the total environment, 2018-01, Vol.612, p.894-902

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2018

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Coastal waters of the South Atlantic Ocean (SAO) sustain one of the highest levels of production of the World's ocean, maintained by dense phytoplankton winter blooms that are dominated by large diatoms. These blooms have been associated to calm weather conditions that allow the formation of a shallow and well illuminated upper mixed layer. In Bahía Engaño, a coastal site in Patagonia, Argentina (chosen as a model coastal ecosystem) winter blooms recurrently peaked on June and they were dominated almost entirely by the microplanktonic diatom Odontella aurita. However, during the year 2015, a new wind pattern was observed - with many days of northerly high-speed winds, deviating from the calm winter days observed during a reference period (2001–2014) used for comparison. We determined that this new wind pattern was the most important factor that affected the phytoplankton dynamics, precluding the initiation of a June bloom during 2015 that instead occurred during late winter (August). Furthermore, the 2015 bloom had a higher proportion of nanoplanktonic cells (as compared to the reference period) and it was co-dominated by O. aurita and Thalassiossira spp. Other variables such as nutrient supply and incident solar radiation did not have an important role in limiting and/or initiating the June 2015 bloom, but temperature might have benefited the growth of small cells during August 2015. If these changes in the timing and/or the taxonomic composition of the bloom persist, they may have important consequences for the secondary production and economic services of the coastal SAO. [Display omitted] •The high productivity of coastal SAO is maintained by winter phytoplankton blooms.•These blooms peaked during June and were dominated by microplanktonic diatoms.•In 2015 the bloom occurred in August and had a higher proportion of nanoplankton.•Changes in wind patterns caused the shifts in the 2015 phytoplankton bloom.