Evaluation of organic pollution index and the bacteriological quality of the water of the Lake of birds (ELTarf East-Algerian)

The region of el-tarf (extremeeast – algerian) is composed of a variety of wetlands, lake of birds is part of this complexit is an ecosystem of freshwater classified as a ramsar site in 1999, known for its biodiversity. the water pollution of this ecosystem is a reality and represents a serious environmental problem because on the one hand discharges of domestic wastewater in lake, and secondly the intensive farming at the edges of the lake (cattle, sheep).to protect this aquatic ecosystem it has become essential to make this pollution measurable by the evaluation of the index of organic pollution which is calculated according to the method of leclercq maquet (1987), the results show a high organic pollution and also the bacteriological results shows a very important fecal contamination expressed by high rates in total coliforms, fecal coliforms, and fecal streptococci. the principal component analysis (pca) revealed two gradientsthe first one reflects the degree of organic pollution while the second describes the metallic pollution of waters in order to give answers to the main causes of pollution.