The impact of heavy metal pollution gradients in sediments on benthic macrofauna at population and community levels

► Hypotheses on benthic responses to sediment pollution were tested. ► Decrease of species diversity with the proximity to the pollution source. ► Shift of vertical distribution along the transect line attributes to species replacement. ► Larger-size species occurred distant from the pollution source. ► Larger individuals of Heteromastus filiformis occurred closer to the pollution source.