Seaweeds of the Emirates

Abstract

Seaweeds, Cyanobacteria, seagrasses and mangroves are the principal inshore primary producers in the southern basin of the Arabian Gulf. Of these the seaweeds are by far the most diverse with about 120 species recorded from those Emirates bordering the region. Little is still known of the seaweed floras of the two Emirates within the Gulf of Oman (Fujairah, Sharjah). Briefly discussed are the very extensive cyanobacterial mats association with inshore sedimentary environments. Described are the bands of seaweeds, cyanobacteria and sessile animals that are a feature of the intertidal of rocky shores. Much consideration is given to the striking forest-like community that develops seasonally on shallow and often seaward sloping rocky platforms. Large foliose brown seaweeds are the canopy dominants of this community that develops rapidly over the months of lowest sea temperature (‘winter’). Many of these seaweeds decay and are lost during the early summer resulting in a striking transformation of the seascape when the understory of smaller mat/turf-forming and crustose coralline seaweeds becomes evident. Since the late 1990s there has been a ‘phase shift’ with seaweeds replacing stony corals as the spatial dominants on many rocky platforms. The ecological significance of the large biomass of dead and decaying seaweed produced in early summer is discussed. Briefly mentioned are seaweeds as providers of ecosystem services.