Impact of climate change on the water quality of the Danube River lower sector.

Abstract

The paper highlights the effects of climate change on water quality of the Danube River lower sector. The impact of climate change on the water quality of the lower Danube sector was assessed by analysing the multiannual variation of the oxygen and nutrient parameters concentrations and the correlation with the water temperature for the period 1996-2014. From the physico-chemical point of view, the parameters studied are: water temperature, dissolved oxygen, biochemical oxygen demand (BOD5), nitrates, ammonium, nitrites and orthophosphates. This multiannual variation was also analysed at the level of the 12 months (January-December), corresponding to the studied period. Based on the monthly multiannual trends highlighted for water temperature, their effect on the parameters of the oxygen and nutrients regime has been studied and has been interpreted taking into account the processes of the oxygen, carbon, nitrogen and phosphorus cycles, respectively the oxidation of biodegradable organic compounds, nitrification-denitrification processes and phytoplankton production. From the perspective of the hydrological regime, the variation of the oxygen and nutrient parameters with the extreme hydrological regime for the years 2003 and 2006 was evaluated.

Keywords

• climate change
• water temperature
• hydrological regime
• quality parameters
• analysis
• temporal trend