State of Seasonal Environmental Factors of the Hadhramout Coast, Gulf of Aden, Yemen

Mukhaysin, Ali Attaala; Inna I., Shavel; Salem R., Bazar; Tatyana F., Kurochkina; Bogatoz M., Nasibulina

doi:10.21608/ejabf.2018.8183

State of Seasonal Environmental Factors of the Hadhramout Coast, Gulf of Aden, Yemen

Document Type : Original Article

Authors

10.21608/ejabf.2018.8183

Abstract

The present study was conducted during the period from September 2009 to February 2011 to assess temporal and spatial changes in physico-chemical and biological parameters of Hadhramout coast. The investigation was carried out at 5 coastal stations; selected to represent the habitats of the Hadhramout Coast, at a distance of about 1.5 kilometers away from the beach. The results showed that the monthly and locality changes in the parameters were, to some extent, heterogeneous. They were varied as follows: water temperatureranged, as monthly average, from 25 °C in Mukalla station in February to 31°C in Bir Ali in June (annual mean). In general, the means of salinity were more stable, less heterogeneous. Mean of surface salinity of the coast in this study was ranging between (34.3 g/L) during the south-west monsoon to (36.4 mg/L) in the pre-winter monsoon (in the area of Bir Ali). Although a relative heterogeneity in the pH value among the stations, there is a general tendency to decrease during the months of the year towards the Southwestern Monsoon, especially in the area of Bir Ali and Broome. Mean of dissolved oxygen value(DO) in the surface water was 4.86 ± 0.08 mg / L after the summer Monsoon (October of Bir Ali station) to 6.8 + 0.21 Mg / l in winter monsoon (February of Shehir station). The concentration of nutrients can clearly describe the Hadhramout Coast as a high biologically rich water body over most months of the year. Changes of these parameters were discussed in details Turbidity in the coast was characterized by low values and an important spatio-temporal variability. The results point out that this coast contains more dissolved oxygen, more nutrients and fishes.