Culatra Island

Description of Culatra Island

Culatra Island can be divided in three different sectors according to morphodynamic characteristics. The west end of the island is partially artificial due to the presence of the Faro-Olhão Inlet jetty and a seawall/groyne system (built in the early 1980’s). The central sector was the historical location of an ancient inlet. The inherited morphology in this sector reflects the diverse ages of the sand bodies alternating dune ridges with ancient tidal channels and washover breaches. In eastern sector, an inlet dominated evolution occurs, with the development of curved sandy spits. The morphology is constituted by sand ridges separated by active tidal channels on the inner part, and by washover on the ocean side. As the island progressed, the bays between abandoned recurved spits become low-energy environments, where sedimentation gets finer. Sandy back-barriers evolve to tidal flats and salt marshes.
The resent history of Culatra Island elongation is closely related the opening of Faro-Olhão Inlet, its stabilisation, and the scouring process, which greatly reduced the flow through Armona Inlet. Tidal current loss over Armona Inlet ebb delta allowed waves and flood tidal currents to push the shoals landward. This in turn provided the sediment necessary to enlarge Culatra Island.

The barrier embayments on the lagoon side of Culatra Island where chosen as EVREST project study sites because these locations present, during the last decades, the environmental succession from a sandy shore to saltmarsh.

Aerial photograph of Culatra Island, with three shoreline dates represented. The irregular shape of the lagoon margin of the barrier is evident. Urban areas are located on the Western end, next to Faro-Olhão Inlet (Farol settlement) and on the central prominent inner margin (Culatra settlement).
In the slideshow of raster datasets collected and integrated in the EVREST GIS database, given below, you can see the evolution of Culatra for the period of 1947 to 2014. Information and credits for each mosaic are provided in the caption. Navigation buttons are provided for users on desktop devices, while users on mobile devices can swipe through frames.