Phytoplankton in Nutrient-Rich Waters of the Bay of Arguin, Mauritania19.7N 16.4W
The Bay of Arguin, or Banc d’Arguin, is a bay on the Atlantic shore of Mauritania. It is south of Cap Blanc, north of Cap Timiris, and contains the islands of Arguin (above center) and Tidra (below). The bay also contains the 12,000 km² Banc d’Arguin National Park. Here, its waters appear greenish due to nutrient-rich offshore waters teeming with phytoplankton.
The bay is an area of shallow water and tidal flats between the Sahara and the upwelling system off the Mauritanian coast. Hydrographically the Banc d’Arguin can be characterized as a large-scale negative estuary with higher salinities near the shore. It is concluded that ultimately the Banc d’Arguin ecosystem is fueled by nutrients and organic matter derived from the upwelling area.
The inner part of the Banc d’Arguin system is dominated by a detritus-based benthic foodweb in which seagrasses are the principal primary producers. Little of the seagrass production seems to be exported to other parts of the system or other areas. Zooplankton and zoobenthos biomasses are relatively low, but nevertheless support high densities of consumers. Aquatic birds are especially numerous.