Twenty-eight years of ecosystem recovery and destabilisation: Impacts of biological invasions and climate change on a temperate river

Research output: Contribution to journalResearch articleContributedpeer-review



Most river ecosystems are exposed to multiple anthropogenic stressors affecting the composition and functionality of ben-thic communities. Identifying main causes and detecting potentially alarming trends in time depends on the availability of long-term monitoring data sets. Our study aimed to improve the knowledge about community effects of multiple stressors that is needed for effective, sustainable management and conservation. We conducted a causal analysis to detect the dom-inant stressors and hypothesised that multiple stressors, such as climate change and multiple biological invasions, reduce biodiversity and thus endanger ecosystem stability. Using a data set from 1992 to 2019 for the benthic macroinvertebrate community of a 65-km stretch of the upper Elbe river in Germany, we evaluated the effects of alien species, temperature, discharge, phosphorus, pH and abiotic conditional variables on the taxonomic and functional composition of the benthic community and analysed the temporal behaviour of biodiversity metrics. We observed fundamental taxonomic and func-tional changes in the community, with a shift from collectors/gatherers to filter feeders and feeding opportunists prefer-ring warm temperatures. A partial dbRDA revealed significant effects of temperature and alien species abundance and richness. The occurrence of distinct phases in the development of community metrics suggests a temporally varying impact of different stressors. Taxonomic and functional richness responded more sensitively than the diversity metrics whereas the functional redundancy metric remained unchanged. Especially the last 10-year phase, however, showed a decline in richness metrics and an unsaturated, linear relationship between taxonomic and functional richness, which rather indi-cates reduced functional redundancy. We conclude that the varying anthropogenic stressors over three decades, mainly biological invasions and climate change, affected the community severely enough to increase its vulnerability to future stressors. Our study highlights the importance of long-term monitoring data and emphasises a careful use of biodiversity metrics, preferably considering also community composition.


Original languageEnglish
Article number162678
Number of pages12
JournalScience of the total environment
Early online dateMar 2023
Publication statusPublished - 1 Jun 2023

External IDs

PubMed 36894073
Scopus 85149904067
ORCID /0000-0002-4951-6468/work/142256773


Sustainable Development Goals


  • Aquatic biodiversity, Benthic macroinvertebrates, Functional redundancy, Functional richness, Invasive species, Mean summer temperature, Rivers/chemistry, Environmental Monitoring, Biodiversity, Animals, Climate Change, Ecosystem, Introduced Species, Invertebrates