Physicochemical quality of Wadi Bounamoussa surface waters (Northeast of Algeria)

Abstract

Nitrogen is a nutrient that causes inland waters and marine environements' eutrophication. The latter has become a worldwide environmental concern that considerably lessens the aquatic environments' quality. This study has focused on physicochemical aspect of Wadi Bounamoussa water, by the diagnosis of the watercourse eutrophication. The river drains a watershed mainly characterized by agricultural activities based on irrigated crops and livestock of sheep and cattle. Fertilizers being Nitrogen inputs and livestock waste are potential pollution source. Nitrogen can get into the watershed's hydro-system in the form of minerals or organic. Temperature, pH, dissolved oxygen, NH4+, NO3-, NO2- were monitored in water samples taken in September and in December 2013 corresponding to the low season, and also in March and June 2014 corresponding to water high season. These samples were obtained from ten stations located along the river downstream sequence between El Cheffia dam and El Batah River mouth. Few observations have been made based on results obtained from the physicochemical analysis. Temperature, pH level, electrical conductivity as well as silica were significantly higher during low water periods comparing to high ones. It has been noticed from the analysis of various water sampling stations the presence of chloride ions with an increasing gradient from upstream to downstream, where it's content has fluctuated between 30.52 mg·dm-3 and 9964.6 mg·dm-3. In conclusion, the presence of inorganic nitrogen is not considered as an eutrophication risk on the watercourse and its receiving environment.