Implementation of an active 'bryomonitoring' network for chemical status and temporal trend assessment under the Water Framework Directive in the Chiampo Valley's tannery district (NE Italy)

► Transplanted bryophytes provide reliable water body classifications for trace metals. ► Transplant-based investigations allow point source assessment and trend analyses. ► The 'moss bag' technique improves environmental monitoring and management. ► A novel biomonitoring network was implemented to monitor spills in industrial areas. ► The network leads local authorities in optimizing environmental protection policies.