100 m m-2 Dreissena mg.m-3 secchi in mm Fisheries
Bream kg.ha-1 mussel N.m-2 Fisheries
fishery bream disturbance sediment turbidity Chara beds Dreissena mussels After Lammens et al. (2004)
Conditions today: positive trends in P, N, CHL and Secchi some clear water, macrophyte-dominated lakes still many turbid water lakes, no macrophytes Short-term action: Sewage: 4-th step in treatment plants in some catchments Agriculture: reduce surface run off by smart agr practices Fishery: reduce bream to help macrophytes & mussels
Clear water lakes 2015? Yes, … if bream fishery is accepted as management tool Long-term perspectives? Natural water levels Flooding of adjacent land areas (following sea level rise) Letting the sea back in?
Mission: learning, inspiration, helping,.. Integrating water policy, lake science and lake management,.. Organization: members on list - national/local government, consultancy, universities, stake holders - informal platform, no membership dues, free meetings/lunches (rotating hosts pay for that) - programme committee (<0.5 ftu), administration by CWM (Centre for Water Management, = ex RIZA)
Activities: - meetings 2x per year, field excursions - international excursions (Broads UK, Müritzsee D, Jutland DK?) - sounding board for case studies/restoration plans - national eutrophication survey - website (www.shallowlakes.net, under restoration )www.shallowlakes.net
- EU network of national networks Social network & virtual network Sowing the seeds for: European Lake Management Society (ELMS)? First EU Lake Management Conference 2010? See also: