New publication in Limnologica:

Aquatic organisms are inherently dependent on the environmental conditions of their habitats. However, the responses of different organism groups vary considerably along the wide range of environmental gradients that shape freshwater ecosystems. A research team around Hannah-Marie Stappert investigated the responses of five ecologically important organism groups to multiple environmental gradients in order to assess their resilience in the face of ongoing climate change.

Environmental factors strongly influence freshwater ecosystems, and changes in these factors are accompanied by shifts in the abundance and composition of aquatic organisms. However, not every environmental factor affects every organism group to the same extent. Flow velocity, nutrient concentrations, water temperature, solar radiation, shading, and elevation all play important roles. In addition, the composition of biological communities influences how individual species respond to these environmental stressors.

Among the studied groups, macrophytes exhibited the greatest variation in their responses to environmental stressors, particularly to shading and sunlight. In contrast, riparian vegetation showed the lowest variability, as it is primarily affected by urban development, river channelization, and invasive species rather than by the environmental factors examined in this study. Unlike riparian plants, aquatic macrophytes are continuously exposed to changing environmental conditions without the possibility of escaping them. Diatoms responded most strongly to variations in light availability. Macroinvertebrates, in turn, were particularly influenced by flow velocity, which reflects stream habitat structure, as well as by water temperature.

Different organism groups respond to environmental stressors and hydrological variability in distinct ways and with varying degrees of sensitivity. Assessing the ecological status and future trajectories of freshwater ecosystems therefore requires the monitoring of multiple taxa. Their combined responses can reveal otherwise undetectable hydrological changes and provide valuable insights into the impacts of ongoing climate change on running waters.

Original Publication: https://doi.org/10.1016/j.limno.2026.126365