TERRAPUB Journal of Oceanography

Journal of Oceanography, Vol. 62 (No. 1), pp. 83-89, 2006

Nutrient Fluxes from Deep Sediment Support Nutrient Budget in the Oligotrophic Waters of the Gulf of Aqaba

Mohammed Rasheed*, Saber Al-Rousan, Riyad Manasrah and Fuad Al-Horani

Marine Science Station, P.O. Box 195, Aqaba 77110, Jordan

(Received 24 May 2005; in revised form 12 September 2005; accepted 19 September 2005)

Abstract: The role of deep sediment in supporting nutrient budget in the Gulf of Aqaba has been investigated by estimating the flux of inorganic nitrogen, phosphate and silicate. Fluxes were calculated directly by pore water profiles and indirectly by chamber incubations carried out onboard the RV Meteor cruise. The results showed that maximum potential fluxes calculated by chamber incubations were higher than those calculated by porewater profiles for all nutrients (6.4-28.5 fold). This has been attributed to the additional flux due to bioturbation and flux from advective porewater exchange in the case of chamber incubation, while porewater fluxes represent diffusive ones. Using a rough estimation considering flux results in addition to the sediment area and water mass of the Gulf of Aqaba, we estimate that 3.3 × 105, 6.4 × 104 and 6.5 × 106 kg year-1 of inorganic nitrogen, phosphate and silicate respectively are effused from deep sediments to the water column. This quanitity would certainly support the primary productivity in the oligotrophic water in the Gulf of Aqaba.

*Corresponding author E-mail: m.rasheed@ju.edu.jo

[Full text] (PDF 236 KB)