The Response of Two Halophytic Species to Crude Oil-Contaminated Soil in the Northern Western Region of Egypt

A site that covers over 20 acres of coastal saline depression in the western Mediterranean coastal desert of Egypt (El-Hamra station, the main crude oil pipeline terminal in Alamein) is contaminated with petroleum. This area, prior to contamination by crude oil was dominated by different common halophytes. Atriplex halimus (L) and Arthrocnemum macrostachyum (Moric.) are now the most dominant species growing in this site. These species adapt themselves through different growth parameters, physiological and biochemical changes. Crude oil affects significantly on soil fertility and increasing pH (8.4). Importance value (IV), height and canopy diameter of the two studied species exhibited an increase in the polluted site. Organic metabolites such as fatty acids, antioxidant compounds and protein fractions in shoots of studied species which collected from the oil-contaminated and non-contaminated sites were examined. Fatty acid fractions exhibited the opposite performance especially the content of saturated C: 16 (palmitic), mono and di-unsaturated C18:1 (oleic) and C18:2 (linoleic) fatty acids as well as poly-unsaturated C18: 3 and C20: 3 (Omega -3 fatty acids). Antioxidant activity and most examined phenolic compounds were increased in A. macrostachyum which grow in a contaminated site. Protein fractions in A.halimus attained with enormous variations therefore, a Genomic Templet Stability (GTS %) was lower than in A. macrostachyum under contamination. The biochemical and behavioral responses to oil pollution varied with the two different species may be according to the genetic make-up of individuals, which make the two studied species useful and effective tools for phytoremediation purposes.