Correlations between chemical, hydrological and biotic factors in rivers from the protected area of Tisa Superioară, Romania

Abstract

This paper aimed to evaluate the water quality of several rivers (Șugătag, Sapanta, Isa, Vișeu and Tisa), vegetation and fish population in the protected area of ROSCI0251Tisa Superioară, Romania to determine the extent to which the anthropic activities (tourism activities and livestock) affect the water characteristics and implicitly it’s quality. Results indicated contamination with NH4+, Fe, Ni, Cr and Mn, with values ranging from 0.14 to 0.83 mg/L NH4+, 0.07–0.76 mg/L Fe, 2.9–31 mg/L Ni, 1.38–59 mg/L Cr and 7.6–127 mg/L Mn, caused by anthropogenic activities. According to the pollution indices scores, samples were characterized by low, medium, and high pollution levels. HPI (Heavy metal Pollution Index) and HEI (Heavy metal Evaluation Index) scores ranged between 21.6 and 54.4 and 1.5–8.4, respectively. Risk assessment indicated no risks at metals through ingestion or dermal contact. The chronic daily intake ranged between 9.08 × 10−6 and 2.09 and the hazard quotient ranged between 9.61 × 10−7-3.45 in both dermal and ingestion pathways. The fish population included 23 species. The ichthyofaunal assessments indicated good quality and stability. This study provides important data for the riparian population, researchers, and even policymakers, regarding the quality status and potential pollution degree of surface waters in the protected area of Tisa.