Chemical and Organic Contamination Degree of Waters in the Lacustrine Complex of El Kala (Northeastern Algeria)

The lacustrine complex of El Kala (LCEK) is recognized for its biodiversity richness and its perennial water resources, which have allowed it to be included in the Ramsar List thanks to the ecological and scientific importance of its wetlands. The lacustrine complex has, therefore, been under protection against all harmful human activities for its preservation. However, the vicinity of the wetlands has been encroached in the last decades, as exemplified by increased socioeconomic activities at the expense of the lacustrine ecosystem. The objective of this work is to identify the degree of chemical contamination of waters and of pollution by organic bodies in relation to the resulting domestic discharges and to the use of fertilizers in agriculture. Therefore, four superficial and six groundwater samples were collected and analyzed in the laboratory for some major chemical and organic parameters, namely sodium, sulfates, chlorides, nitrates, biological oxygen demand, chemical oxygen demand, phosphates, total phosphorus, ammonium, and dissolved oxygen. The contamination index (CI) and the organic pollution index were determined. The CIs’ values for the majority of the samples were lower than 7, indicating a low chemical contamination of waters. The organic pollution index ranged from high (2.3) to very high (1.5–1.8), suggesting the waters are polluted by organic substances. Also, the waters in the LCEK are likely charged with organic bodies in high concentrations, which may cause a risk of pollution of an anthropogenic origin that will have a negative impact on the maintenance of the ecosystem.