Trend Analysis of Water Quality Parameters in the Middle Part of the Danube Flow in Serbia

Abstract

The Danube River plays significant role not only for preserving natural ecosystems. The aim of this paper is to examine the Middle Danube water quality in the part flowing through Serbia in section Bezdan -Banatska Palanka. Water quality data were examined for seven control points for period 2004-2018, for seven parameters: suspended solids (SS), dissolved oxygen (DO), electrical conductivity (EC), nitrates (NO3 –-N), total phosphorus (Ptot), biochemical oxygen demand (BOD5) and chemical oxygen demand (COD). Data analyses included the application of ANOVA, linear regression analysis and Mann-Kendall trend test. The Mann-Kendall tests in most (32/49) cases, i.e. in 65 %, confirmed the non-existence of a significant trend. Significant downward trends were confirmed in 17 cases. Water quality improvement was confirmed at following control points: Bezdan for NO3 –-N, Ptot and BOD5; Bogojevo for NO3 –-N, Ptot, COD and BOD5; Novi Sad for Ptot, BOD5 and COD; Slankamen for BOD5 and COD; Smederevo for NO3 –-N and COD; Banatska Palanka for NO3 –-N. Slight deterioration of water quality was confirmed only in two cases, at the Zemun and Smederevo where DO was decreasing. Water quality for the examined period was stable and can be characterised as excellent and/or very good (class I or class II). Results emphasise fact that water quality trends monitoring reveals river sectors where the process of water quality degradation is ongoing. Timely detected critical river sectors can draw the attention of decision-makers, who can improve the existing legislation that would lead to water quality improvement.

Water quality evaluation of the Danube River basin in Bačka (northern Serbia) using multivariate statistical techniques

“…Pollution still remains high, especially from nutrients and hazardous substances (ICDPR 2007b). Numerous authors have investigated the issue of the Danube's water quality as it flows through Serbia (Durlević 2020;Leščešen et al 2018;Milanović, Kovačević-Majkić, Milivojević 2010;Mladenović-Ranisavljević et al 2012;Ocokoljić, Milijašević, Milanović 2009;Takić et al 2012;Takić et al 2017;Walker et al 2015) and Autonomous Province (AP) of Vojvodina (Milanović, Milijašević, Brankov 2011;Milovanović et al 2019;Pantelić et al 2013;Pantelić et al 2015;Salvai et al 2022;Zemunac et al 2021).…”

Romanian Danube River Hydrocarbon Pollution in 2011–2021

“…The most serious obstacles to internationally integrated river management do not appear to be technical, but political [4]. An example of a river of international importance is the Danube [20,21], which is a cross-border river flowing through ten countries. Its basin covers 19 European states [22][23][24][25][26][27].…”