ASSESSMENT OF SEASONAL VARIATIONS OF WATER QUALITY IN MOŞNA RIVER (SIBIU COUNTY)
HOAGHIA ALEXANDRA, LEVEI ERIKA, CADAR O., RISTOIU D.
ABSTRACT. – Assessing of seasonal variations of water quality in Moşna River (Sibiu County). Evaluation of spatial and temporal variations of the river water chemistry represents a significant aspect of water quality assessment and future trends prediction. The aim of this work was to assess the spatial and temporal variation of Moşna River water quality using graphical and statistical methods. The pH, electrical conductivity, nitrate and nitrite contents of surface waters from 14 monitoring sites (10 sites along the river and 4 sites on the most important wastewater effluents) were monitored monthly from autumn 2013 to summer 2014. Box-and-whisker plots were used to evaluate the seasonal variations of water quality, while hierarchical cluster analysis was used to evaluate the spatial variation of water quality. Results indicated that the studied parameters varied mostly during spring and summer, while during the cold season the parameters variability was low. For the periods rich in precipitations (April - May) high values for pH and electrical conductivity were measured, as a consequence of meteoric water overflowing into the river body. High concentrations of nitrite and nitrate were observed during all year in all sampling sites.
Keywords: surface water, spatial and temporal variations, box-and-whisker plots.