Reduced genetic diversity of freshwater amphipods in rivers with increased levels of anthropogenic organic micropollutants

Anthropogenic chemicals in freshwater environments contribute majorly to ecosystem degradation and biodiversity decline. In particular, anthropogenic organic micropollutants (AOM), a diverse group of compounds including pesticides, pharmaceuticals, and industrial chemicals, can significantly impact freshwater organisms. AOM were found to impact the genetic diversity of freshwater species, however, the degree to which AOM cause changes in population genetic structure and allelic richness of freshwater macroinvertebrates remains poorly understood. Here, the impact of AOM on the genetic diversity of the common amphipod Gammarus pulex (Linnaeus, 1758) (clade E) was investigated on a regional scale. The site-specific AOM levels and their toxic potentials were determined in water and G. pulex tissue sample extracts for 34 sites along six rivers impacted by wastewater effluents and agricultural run-off in central Germany. Population genetic parameters were determined for G. pulex from the samp...