News

In water bodies, stones, aquatic plants or the substrate often feel slippery. The cause of this is the so-called biofilm, a wafer-thin layer of countless microbes. They form the basis of aquatic food webs, cleaning and detoxifying the water by breaking down organic pollutants. Using lakes in the French Pyrenees as an example, researchers from the Institut National Polytechnique de Toulouse and the IGB have now shown that the microbial biofilm composition is changing rapidly as a result of climate change and that toxic cyanobacteria are increasing.

This summer, the water shortage in Europe continues to preoccupy politicians and the public. Small standing water bodies such as natural or artificial ponds, kettle holes or park waters are particularly suffering from the lack of water. In order to raise awareness of this problem and to point out options for action for policymakers, authorities and the civil society, IGB has today published a new IGB Dossier on this important type of water body.

An international research team has analysed the state and development of biodiversity in European rivers. As the extensive study shows, development has stagnated after initial improvement; many river systems have not been able to regenerate completely.

Researchers from the Chinese Ministry of Natural Resources in Xiamen and the IGB have identified a natural fungus-bacteria consortium that metabolises nitrate particularly efficiently and consistently. This could be crucial for the further development of biotechnological approaches in water treatment and provides further evidence of the important role of fungi in aquatic ecosystems.

Reeds are dying in many of Europe's lakes. The causes are manifold. Researchers from IGB and the Humboldt Universität zu Berlin (HU Berlin) have now identified high sulphate concentrations as a result of mining in Lusatia as one of the causes of the decline of reeds in Berlin's lakes. They analysed data from 14 lakes in the Berlin catchment area for the period 2000 to 2020. Rising sulphate concentrations are associated with a decline in the reed beds.

Microplastics are found in lakes and reservoirs around the world. Pollution reaches even the most secluded places where human influence is minimal. Moreover, concentrations of microplastics in freshwaters are sometimes higher than in subtropical gyres, the marine areas where large amounts of waste accumulate. These are the findings of an international study of 38 lakes and reservoirs led by the University of Milan-Bicocca in Italy, with the participation of IGB, and published in the journal Nature.

A team of behavioural ecologists from IGB and the Humboldt-Universität zu Berlin (HU Berlin) is investigating how animals hunt in groups. Animals in water hunt differently than animals on land, which is partly due to the different size ratio between predator and prey. One example is striped marlin, which belong to the billfish family. Motivation may play a greater role than dominance hierarchy during resource division, but the large fish get out-competed by sea lions when the two predators attack the same prey.

Today, Federal Environment Minister Steffi Lemke visited the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) in Berlin to learn about the first interim results of the special investigation programme on the environmental disaster in the Oder River (“ODER~SO”), which has been funded by the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection (BMUV) since February 2023. Fish stocks in the Oder River have declined by 53 to 67 per cent as a result of last summer’s environmental disaster, especially midstream.