Present Environmental Status of the Shuaiba Lagoon, Red Sea Coast, Saudi Arabia.

Shuaiba Lagoon is located about 80 km south of Jeddah city, Saudi Arabia. Its environmental characteristics were determined. The macro-fauna and flora were also sampled and identified. Extreme values for salinity (60‰) and water temperature (33°C) were recorded and that may be due to its shallowness and small volume and occurrence under arid warm climate. Lagoon water pH was low (8.3), likely, as a result of re-mineralization of organic matters. These extreme variables exerted probably a stressful natural environment on the calcareous macro-fauna (molluscs and corals) as indicated by dominance of gastropod Cerithidea pliculosa and pelecypod Mytilus edulis in the lagoon. Corals could not tolerate these conditions so they were only recorded close to the inner- and outside inlet of the lagoon. On the contrary, these environmental conditions are probably favorable for mangroves, seagrasses and macro-algae (and Cyanophytes) as indicated by their proliferation in the lagoon. [ABSTRACT FROM AUTHOR]