Seasonality and Correlations between Water Quality Parameters in the Lower Danube at Chiciu for the Period 2010-2012

Abstract

The Danube River receives tributaries with different pollution loads, according to the social-economic characteristics of the adjacent regions. Water quality monitoring data from Chiciu, Calarasi county, Romania, for the three-year period (2010-2012), were analysed using statistical methods in order to identify correlations between parameters, as well as their evolution during the study period. The analysis has confirmedpositive correlations between nitrates and total nitrogen and between ortho-phosphates and total phosphorus. Negative correlations were found between water temperatures on one side and dissolved oxygen and nitrates on the other side. These parameters have a seasonal evolution, with high temperatures and low dissolved oxygen and nitrates levels during summer periods. Linear regression highlights decreasing nutrients pollution during the study period, which may be due to improved wastewater treatment along Danube tributaries.

Long-Term Trends in Water Quality Indices in the Lower Danube and Tributaries in Romania (1996–2017)

“…There are several scientific studies that analyzed individual parameters in the Danube and how they evolved over longer periods of time [ 30 , 31 ] and a number of studies that looked at the complex interaction between parameters [ 32 ] and between parameters and their drivers [ 33 , 34 , 35 , 36 , 37 , 38 , 39 ]. However, to support authorities and decision makers, and to communicate information to the public, an overall assessment of water quality can be a very useful tool.…”