The salt content in the Oder rose again – cause unknown
In the Oder, measurements have again found a high salt content. The search for the cause strains relations with neighboring Poland.
Berlin. Lots of dead fish in the water: the memories of the images in midsummer are still present for many. Now have goals in orthe border river between Germany and Poland, again increased salinity established. The reason for the repeatedly increased salt load remained unclear over the weekend. First “Zeit Online” had reported on it.
Only in August had there been one in the Oder. Experts saw the combination of salt discharged from industry, low water in the river and high summer temperatures as the causes of the environmental disaster. As a result, there was one in the Oder toxic species of algae (Prymnesium parvum) multiplied in large numbers. Toxins from these algae in river water destroy the gills of aquatic animals, causing them to suffocate. In total, several hundred tons of dead fish washed ashore. Other river animals are said to have died in large numbers.
Salt content in the Oder: correspondingly increased as with mass culling of fish
New data from a measuring station from the State Office for the Environment in Brandenburg in Frankfurt (Oder) now indicate a similarly high salinity in the Oder as in fish kills this summer. This could indicate that dangerous levels of pollutants have again been released into the river.
Christian Wolter, aquatic ecologist from the Leibniz Institute for Aquatic Ecology and Inland Fisheries, called on Monday for the amount of salt discharged into the Oder to be quickly limited. He fears otherwise in the future Summer – with low water and high temperatures – again a big fish kill.
The search for reasons also has a political dimension: in the long-standing dispute with Poland, the state of Brandenburg wants to sue the Polish side against the expansion of the Oder. This must stop the construction work. The handling of fish kills also further strains the relationship with the neighboring country. There is disagreement about where most of them pollutants comes from. In September, a joint investigation report failed. The German side had repeatedly accused the Polish authorities of a lack of transparency in the investigation.
The Ministry of the Environment does not expect the toxic algae to spread
Brandenburg’s environment ministry announced, citing data from the state environment agency, that the observed conductivities in the Oder were below peak values, which was measured in the summer, but well above the average values of recent years. The electrical conductivity of the water is an indication of the salt content. The values in the stream will continue to be monitored, according to the Ministry of the Environment. Currently, with the lower water temperatures of 13 degrees, there is no mass gain algae expected.
Water ecologist Wolter told “Zeit Online” that since there is currently twice as much water in the Oder as in summer, the amount of salt loads is at least as high or even higher than in summer. The measured salt content – it is sodium chloride, i.e. common salt – is currently not dangerous for the fish, Wolter said. It could be different in the summer, when the water was low and the temperatures high and there was a lot of nutrients in the Oder, so that the toxic algae could multiply again. He was shocked that after environmental disaster nothing will be done about the cause.
The bordering middle Oder from Ratzdorf to Kietz (Oder-Spree district) has carried large salt loads for years, the state ministry said. The “cohabitation” that occurs in the Oder has evidently stuck to both the high basic load as well as adjusted to the recorded fluctuations and peaks. The Federal Environment Ministry in Berlin pointed out, after a request, that the state was responsible.
Environment Minister Axel Vogel (The Greens) announced at the end of September that Brandenburg wanted it environmental disasters how the fish that die in the Oder can be recognized more quickly in the future. It will be checked whether and how the measurement system and the reporting chains can be optimized.
Lawsuit to prevent Poland’s expansion of the Oder
In addition, the Ministry of the Environment is preparing a legal action against the Oder extension, which must be submitted by November 16, a ministry spokesman said on Saturday. “Märkische Oderzeitung” had previously reported. “In our opinion, the expected transboundary environmental impact and the current ecological state of the Oder have not been sufficiently taken into account,” the spokesman said.
Poland will Expansion of the Oder promote and cites better flood protection as a goal. Environmentalists, on the other hand, believe that the regulation of the Oder poses a threat to the river’s ecosystem. After the massive fish die-off, the Federal Environment Ministry in Berlin said that the Oder should recover from the environmental disaster. Expansion measures stand in the way of successful regeneration. Environmental groups in Germany have already complained about the Oder expansion.
This article first appeared on morgenpost.de.