Effect of pollution on the hydrochemical characteristics of different water types in El-Max Bay area, west of Alexandria, Egypt
Abstract
El-Max Bay, west of Alexandria, has a surface area of about 19.4 km2 and volume 190.3 x 106 m3. It receives a heavy load of wastewater (2.4 x 109 m3/year), both directly from industrial outfalls and indirectly from Lake Maryut via El-Max Pumping station. Seven marine trips were carried out in El-Max Bay during the period from January 1988 to January 1989 using a motor boat. Temperature, salinity, pH, alkalinity, dissolved oxygen, oxidizable organic matter, hydrogen sulphide, phenolic compounds and nutrient salts were measured at surface and bottom from seven sampling stations.
The surface water temperature varies from a minimum of 14.2 °C in January to 28.9°C in August. Based on the distribution of surface salinity, four types of water are identified:
Mediterranean sea water (salinity > 38.5‰), diluted sea water with a salinity range between 30 and 38.5‰, mixed water (salinity 10 to 30‰) and mixed land drainage with a salinity of less than 10‰. The hydrochemical characteristics of these water types are discussed in detail. The present work deals with the first attempt to study the pollution in El- Max Bay based on the determinations of the total phenolic compounds in the Bay water. The total phenol is generally present in higher concentrations in the nearshore stations decreasing seaward. At the surface, it varies from a maximum of 231.11 ppm nearshore in June to a minimum of 53.16 ppm at the offshore stations. At the bottom, it decreases from 195.22 ppm nearshore in April to reach 21.21 ppm in February at the open sea stations.
