Basic physical and chemical properties of some coastal Mediterranean lagoons

Abstract

In the present study, the physical and chemical properties of some coastal lagoons which include water temperature, salinity pH, dissolved oxygen, phosphate, nitrate, nitrite and ammonia were evaluated to study their environmental status. The water temperature was high in summer and it reached about 28.07 °C at Kalige Um-Alshawsh inlet and then it was drop to 14.39 °C at the Gulf of Bomba. Salinity was found to be high (41.95 ppt) in Autumn at the Gulf of Bomba and less salinity value (38.20 ppt) was recorded in Summer at Marsa El-Katayta. The highest concentration of dissolved oxygen was recorded as 9.59 ppm in Winter at Um Alshawsh inlet and a lower concentration recorded was 5.69 ppm in Summer and was measured at the same station. Highest pH value (8.62) was recorded in Summer at Um Alshawsh inlet while the lower value was observed as 7.84 in Winter at the Gulf of Bomba. Higher value of phosphate was recorded as 2.152 µg-at.P-PO₄^3-.l^-1 in Summer at the Gulf of Bomba and a lower concentration of phosphate was recorded as 0.369 µg-at.P-PO₄^3-.l^-1. Higher value of nitrate was observed as 4.795 µg-at.N-NO₃^-.l^-1 in Summer at Marsa El-Katayta and the lower value was recorded as 0.577 µg-at.N-NO₃^-.l^-1 in winter at port Bordia, while the higher value for nitrite was recorded as 0.741 µg-at.N-NO₂^-.l^-1in Summer at Um El-Shows inlet and the lower value was observed as 0.242 µg-at.N-NO₂^-.l^-1at the same station. Higher ammonia value (1.044 µg-at.N.l^-1) was noticed in the Autumn season at the Gulf of Bomba where non detectable level had been noticed in Summer season at Marsa El-Katayta. The results of the present research exhibited the basic addition to understand these environmental conditions for future activities such as the possibility to exploit, develop and to predict the environmental variables.