Evaluation of Freshwater Water Quality with Indexes and GIS-Based: A Case Study, Guren Stream (Kure Mountains National Park, Western Black Sea Basin, Turkey)

Abstract

Turkey is separated into 25 river basins, and the Guren Stream is found in Kastamonu Province's West Black Sea Basin. Guren Stream originates inside the borders of Kure Mountains National Park and flows into Black Sea. Kure Mountains National Park, in addition to being one of the 9 hot spots to be protected in Turkey, is the country's first Protected Area Network Parks (PAN park). At this research, monthly stream water samples were taken from different 14 stations in the Guren Stream between 2018-2019. Subsequently, the concentration of 28 parameters, consisting of pH, water temperature, electrical conductivity, suspended solid matter, salinity, total hardness, total alkalinity, dissolved oxygen, chemical oxygen demand, biochemical oxygen demand, NH4-N, NO2-N, NO3-N, SO4, SO3, PO4-P, Cl, Fe, Na, K, Mg, Ca and six potential toxic elements, including Pb, Cu, Cd, Hg, Ni, and Zn were measured. The results were compared to the criteria of the Turkish Water Pollution Control Regulation and the World Health Organization (WHO). In addition, the association between the obtained data and Geographic Information Systems, spatial distribution maps, ecotoxicological indexes, quality classifications, multivariable statistical pearson corelation and factor analysis inter-parameter associations were evaluated. According to the results, the Guren Stream's water is of the highest quality, designated first class, and did not exceed WHO limits. According to water quality and ecotoxicological indexes, Guren Stream is classified as "excellent, good, no pollution, permissible and low." To identify relationship between parameters, correlation and factor analysis were applied to data. Natural sources, anthropogenic activities and forestry factor inputs were determined as the main accumulation sources of river by the result.