Selected publications

Study of the effects of macrophyte removal on phytoplankton, zooplankton and macroinvertebrates at five sites with highly variable characteristics repeating the same Before-After-Control-Impact design to disentangle general from site-specific effects. Macrophyte removal had negative effects on biodiversity, esp. on zooplankton and macroinvertebrates. It had positive effects on phytoplankton.

the researchers have set up a database with geo-referenced occurrence records of four groups of freshwater invertebrate taxa across Cuba. Detailed knowledge of the spatial distribution of freshwater species is an important basis for monitoring changes in aquatic ecosystems.

The authors undertook the first global assessment of the impacts of alien species on native freshwater megafauna using the Environmental Impact Classification for Alien Taxa framework. Negative impacts on native freshwater megafauna were caused by 61 alien species from diverse taxonomic groups, including both freshwater and terrestrial alien species, and both vertebrates and invertebrates.

Thanks to the commitment of nearly 100 researchers, the EPTO-database is the first global data source regarding geo-referenced and freely available data sets on aquatic insect occurrences - Mayflies (Ephemeroptera), stoneflies (Plecoptera), caddisflies (Trichoptera) and dragonflies (Odonata) - worldwide. 

This is a review of multiple-stressor research in freshwaters, particularly studies that have experimentally manipulated multiple stressors and measured responses of multispecies assemblages. There is a gap between biotic interactions under multiple stressors and ecosystem recovery pathways after restoration, indicating a disconnect between multiple stressor research and environmental practice.

Multiple stressors can affect species indirectly through either abiotic variables or impacts on non-target species. Stress tolerance is the key determinant of responses to increasing stress intensity. Dispersal and biotic interactions are the two key mechanisms governing responses to the release from stressors.

The authors explored how spatial and temporal variability of lake food webs and their links to the terrestrial environment affect trophic transfer efficiency (TTE). They suggest that TTE can be estimated as mechanistic expression of energy flow between consumer and producer pairs, or as ecosystem efficiency comparing total sums of heterotrophic production rates with fixation rates of carbon.

Citizen scientists sampled more than 600 freshwaters in Germany. This unique data set provides evidence of 3 trends: first, microorganisms in the sediment show signs of chemical stress and antibiotic resistance in their genetic material. Second, excessive artificial lighting at night alters the species composition of  microorganisms. And third, all studied water bodies emit greenhouse gases.