Editing Daugava (section)

== Environment ==

[[File:Port of Riga on the Daugava river.jpg|thumb|alt=Port of Riga on the Daugava river by findseajobs.com|Port of Riga on the Daugava]]The river began experiencing environmental deterioration in the Soviet era due to collective agriculture (producing considerable adverse water pollution runoff) and hydroelectric power projects.<ref>{{cite encyclopedia |year=2012 |title=Daugava River |encyclopedia=Encyclopedia of Earth |publisher=National Council for Science and the Environment |url=http://www.eoearth.org/article/Daugava_River?topic=78166 |last=C.Michael Hogan}}</ref> This is the river that the [[Vuła (river)|Vula river]] flows into.

=== Water quality ===
Upstream of the Latvian town of [[Jekabpils]], the river's [[pH]] has a characteristic value of about 7.8 (slight [[alkaline]]). In this area, the concentration of ionic calcium is around 43 milligrams per liter, [[nitrate]] is about 0.82 milligrams per liter, ionic [[phosphate]] is 0.038 milligrams per liter, and oxygen saturation is 80%. The high nitrate and phosphate load of the Daugava has contributed to the extensive buildup of phytoplankton biomass in the Baltic Sea; the [[Oder]] and [[Vistula]] rivers also contribute to the high nutrient loading of the Baltic.{{citation needed|date=February 2016}}

In Belarus, water pollution of the Daugava is considered moderately severe, with the chief sources being treated wastewater, fish-farming, and agricultural chemical runoff (such as herbicides, pesticides, nitrates, and phosphates).<ref>{{cite book |title=Towards water security in Belarus: a synthesis report |url=https://read.oecd-ilibrary.org/environment/towards-water-security-in-belarus_488183c4-en#page19 |website=OECDiLibrary |series=OECD Studies on Water |date=2020 |access-date=27 June 2021 |pages=19–20 |doi=10.1787/488183c4-en|isbn=9789264583962 }}</ref><ref>{{cite web |title=Water Report 15 |url=http://www.fao.org/3/w6240e/w6240e13.htm |website=fao.org |publisher=Food and Agriculture Organization of the United Nations |access-date=27 June 2021}}</ref>