Assesment of dissolved oxygen in coastal waters of Benghazi, Libya.

Abstract

Abstract Study was conducted regularly from December 2008 till March 2009 in three habitats in Benghazi coast. The water parameters were taken into consideration and sampling was conducted on surface waters and 30 cm below in the coastal waters by using digital portable meters. Estimation of solid waste material present in the coast was taken to correlate the pollutants present in coastal waters and its influence on dissolved oxygen. A total of 106 samples are sampled and analyzed in three different habitats during December 2008 until March 2009. Caria 56 (52.83%) followed by Zilayana 31 (29.24%) and thirdly Sabre 19 (17.92%). The difference of sampling is because of varied reasons and the available facilities at the site of sampling. Table's 1-17 shows range, mean, standard deviation and coefficient of variance for parameters like water temperature, dissolved oxygen, salinity and pH. Finally, the pollutants in the beach are dominated by plastic in all the three habitats with 36.01% in Zilayana, 33. 47% in Caria and 54.20% in Sabre. Finally it is concluded from the studies that, dissolved oxygen levels will depend on physiochemical parameters, especially temperature, salinity and pH. In addition to that, presence of large amount of plastic and other disposals may pose a severe threat to coastal ecosystem in turn increasing the surface temperatures and over bloom in turn will have an impact on dissolved oxygen and pH.

Keywords

• Key words: Dissolved oxygen (DO), salinity, temperature, pH, pollutants.

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