No abstract

Seasonal changes of tide signal(s), temperature, salinity and current were studied during the years [2004][2005] in the northernmost Gulf of Aqaba, which is under developmental activities, to obtain scientific bases for best management and sustainability. Spectrum analysis revealed permanent signals of tide measurements during all seasons, which represented semidiurnal and diurnal barotropic tides. The other signal periods of 8.13, 6.10-6.32, 4.16 and 1.02-1.05 h were not detected in all seasons, which were related to shallow water compound and overtides of principle solar and lunar constituents and to seiches generated in the Red Sea and the Gulf of Aqaba. Spatial and temporal distributions of temperature, salinity and density showed significant differences between months in the coastal and offshore region and no significant differences among the coastal sites, between the surface and bottom waters and between coastal and offshore waters. Therefore, the temporal and spatial variation of water properties in the northernmost Gulf of Aqaba behave similarly compared to other parts. The coastal current below 12 m depth was weak (3-6 cms -1 ) and fluctuated from east-northeastward to west-southwestward (parallel to the shoreline), which may be related to the effect of bottom topography and/or current density due to differential cooling between eastern and western parts in the study area, and wind-induced upwelling and downwelling in the eastern and western side, respectively. The prevailing northerly winds and stratification conditions during summer were the main causes of the southward current at 6 and 12 m depths with average speed of 28 and 12 cms -1 , respectively.

Surface sediment samples were collected from five stations along the Jordanian coast of the Gulf of Aqaba, Red Sea, during October and November over 2 years, 2000 and 2001. The monthly sedimentation rate also was estimated for the same stations. Collected sediments were analyzed for color, odor, redox potential, grain size, organic carbon, organic nitrogen, calcium carbonate, and total phosphorus. The Hotels area at the northernmost tip of the Gulf of Aqaba, characterized by sandy beaches and sea grass bottom habitat, exhibited the lowest values for redox potential and was associated with a black color. The Phosphate Port area exhibited the highest sedimentation rate, finest grain size, highest organic carbon content, and highest total phosphorus concentration. This is a deposition habitat that receives phosphate particles lost during shipment. The Marine Science Station and the Tourist Camp, typical coral reef habitats, had the highest calcium carbonate and organic nitrogen concentrations. This is directly attributed to the nature of the bottom habitat. Calcium carbonate deposits result from the erosion of hard corals, and organic nitrogen accumulates due to the rapid consumption and recycling of plankton in the coral reef framework. Comparison of the current records with old records from the 1970s and early 1980s indicates significant improvement in the environmental quality at the Phosphate Port. Tracking the coastal management practices over time shows that these improvements in the environmental quality can be attributed both to the zero discharge policy Jordan has followed since 1986 and to improvements in the phosphate handling system by the Ports Corporation.

No abstract

Surface sediment samples were collected from five stations along the Jordanian coast of the Gulf of Aqaba, Red Sea, during October and November over 2 years, 2000 and 2001. The monthly sedimentation rate also was estimated for the same stations. Collected sediments were analyzed for color, odor, redox potential, grain size, organic carbon, organic nitrogen, calcium carbonate, and total phosphorus. The Hotels area at the northernmost tip of the Gulf of Aqaba, characterized by sandy beaches and sea grass bottom habitat, exhibited the lowest values for redox potential and was associated with a black color. The Phosphate Port area exhibited the highest sedimentation rate, finest grain size, highest organic carbon content, and highest total phosphorus concentration. This is a deposition habitat that receives phosphate particles lost during shipment. The Marine Science Station and the Tourist Camp, typical coral reef habitats, had the highest calcium carbonate and organic nitrogen concentrations. This is directly attributed to the nature of the bottom habitat. Calcium carbonate deposits result from the erosion of hard corals, and organic nitrogen accumulates due to the rapid consumption and recycling of plankton in the coral reef framework. Comparison of the current records with old records from the 1970s and early 1980s indicates significant improvement in the environmental quality at the Phosphate Port. Tracking the coastal management practices over time shows that these improvements in the environmental quality can be attributed both to the zero discharge policy Jordan has followed since 1986 and to improvements in the phosphate handling system by the Ports Corporation.