Tiny Berlin pond animals reflected the surrounding city's paved surface
WHAT THE EVIDENCE SAYS
Across 18 Berlin ponds, researchers compared rotifer communities with mapped urban impervious cover and water conditions. The ratio of Brachionus to Keratella rose with imperviousness and dissolved oxygen and declined with elevation. Their model explained 56% of index variation and suggested a stronger additional impervious-cover response where baselines were less paved.
WHY IT MATTERS / OUR READ
Green-infrastructure design should consider runoff and small-waterbody ecology, not just trees shown on an urban master plan. Biological samples can complement land-use maps.
CAVEATS / UNCERTAINTY
An 18-pond single-city observational model does not establish causation or a transferable water-quality standard without seasonal and multi-city validation.
SOURCE
Hydrobiologia — Ehreke et al., 29 October 2026
View original evidence ↗
A rotifer community index suggests a nonlinear signal of catchment imperviousness.
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