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Riverine lakes are a distinct lake type found in geographic regions of Europe shaped by glacial processes. Knowledge concerning their macroinvertebrate communities is scarce and hampers the development of type-specific assessment methods as demanded by the European Union Water Framework Directive (WFD). We compared macroinvertebrate community composition between near-natural riverine lakes and three other types of near-natural lowland lakes to test if communities differ among types. Moreover, we quantified how macroinvertebrate communities from riverine lakes change along a degradation gradient as the basis for developing ecological status classes. Results showed that macroinvertebrate communities significantly differed between riverine and other lowland lake types. The indicator taxa characteristic for near-natural riverine lakes were significantly correlated with environmental characteristics, i.e., comparatively low maximum water depths and high %macrophyte and xylal habitats. Macroinvertebrate communities differed in their taxonomic composition between riverine lake degradation classes, with significant indicator taxa identified for these. We provided empirical evidence that riverine lakes harbour a distinct littoral macroinvertebrate community and recommend establishing riverine lakes as a separate lake type in the Central Plains ecoregion in national typologies for biotic assessments in compliance with the WFD.

Chemical pollution of the aquatic environment is nowadays characterised by increasing levels of anthropogenic organic compounds at low concentrations and is recognised as one of the main drivers of the deteriorated ecological state of European waterbodies. To improve the understanding of the impact of chemical pollution in surface waters, a combined approach of chemical and bioanalytical testing is considered necessary for effective ecologically oriented water management. For this dataset, six 25-L water samples were collected at six sampling sites along the Holtemme River in Central Germany using large-volume solid phase extraction. All samples were analysed by targeted high-resolution liquid chromatography–mass spectrometry (LC–MS) and a selected bioanalytical test battery using effect-based methods. These methods included cytotoxicity assessment, several mechanism-specific CALUXⓇ tests to identify endocrine and oxidative stress-related effects and the fish embryo acute toxicity test to investigate (sub)lethal effects in the model species Danio rerio. This approach provided a dataset that offers a longitudinal characterisation of the chemical pollution and ecotoxicological impacts. The combination of chemical analysis and effect-based analysis is valuable for future studies as it will help researchers, risk assessors and authorities to identify hot spots of chemical pollution, monitor environmental quality standards and recommend mitigation strategies.

We compared the structural and functional attributes of Neotropical macroinvertebrate communities between two natural, two agricultural, and two urban streams. We quantified food resource availability, community structure, secondary production, and consumer–resource interaction strength, attributing them to environmental characteristics. In agricultural streams, secondary production was significantly reduced compared to natural streams, reaching the lowest reported estimates for tropical streams (0.08–0.69 g DW·m−2·year−1 in agricultural streams vs. 1.1–15.8 g DW·m−2·year−1 in natural streams). This decline was primarily attributed to habitat degradation caused by siltation and channelization, alongside stronger top-down pressure in agricultural streams. Conversely, urban streams exhibited a substantial increase in secondary production, ranking among the highest estimates for tropical streams (25.6–191.2 g DW·m−2·year−1). The high secondary production in urban streams was primarily due to substantial increases in fine benthic organic matter, likely originating from poorly treated wastewater. Along with higher resource availability, we also observed a lack of, or insufficient, top-down control by macroinvertebrate predators or fish, which may have promoted higher secondary production in urban streams. This study is the first to quantify land use impacts on energy flows in stream communities in a region particularly threatened by land use change. Future studies should address multifunctional responses to land use changes in both the tropical and temperate realms to shed new light on how stream ecosystem functions in different biomes respond to human impacts. Our findings highlight the urgent need for effective management strategies tailored to address the environmental characteristics of tropical stream ecosystems.