Multicriteria Visual Approach to the Analysis of Water Quality—A Case Study of the Tisa River Basin in Serbia

The aim of this research is to provide the assessment of water quality with a wider scheme of interrelations between the water quality parameters and locations using a reliable visual approach of multicriteria PROMETHEE and GAIA methods. The case study of one of the largest and regionally most important catchment areas on the territory of the Republic of Serbia—the Tisa River Basin—was therein used. The analysis of water quality included scenarios for warm (summer), cold (winter), and average annual period. A partial and complete ranking of locations according to the quality of water was performed by applying the PROMETHEE method and expanded afterward by GAIA method analysis to point out critical locations with endangered water quality (M6, M4, and M11). Identified locations were then investigated in more detail using spider web graphs that revealed water quality variables of concern (PO4-P and N) and indicated the causes of its occurrence. The obtained results are in accordance with the results of physical and chemical tests that are regularly conducted by the official government agencies for environmental protection and the reports that are presented to the public. The presented approach can easily be applied to any water body to point out both the locations with reduced water quality and the specific parameters (causes) that affect the reduction of water quality at these locations, thereby enhancing and strengthening usual water quality assessments as well as water resources management in general