The nutrient dynamics and biological structure of shallow non-stratified lakes differ markedly from that of deep and stratified lakes: for example, the return of nutrients lost through sedimentation is faster and the potential importance of fish and submerged macrophytes as food-web regulators is greater. In addition shallow lakes are more easily influenced by fluctuations in the physical environment caused by wind disturbance, temperature change, etc. Although shallow lakes are often the most common lake type in lowland countries, less attention has been paid to them than to deep stratified lakes and few comparisons have been made between shallow freshwater and brackish lakes. The volume is divided into five main themes, each introduced by an invited speaker:

• Nutrient dynamics with special emphasis on sediment water interactions and changes in loading (Professor Lambertus Lyklema);
• Biological structure and trophic interaction (Professor Stephen T. Threlkeld);
• Submerged macrophytes: dynamics and role in the lake ecosystems (Ass. Professor Kaj Sand Jensen);
• Comparison of freshwater and brackish lake ecosystems (Professor Brian Moss);

• Modelling the impact of nutrients, the biological structure and the recovery process (Dr Marten Scheffer).

  Inhalt

  Brackish and freshwater shallow lakes - different systems or variations on the same theme?.- Does the impact of nutrients on the biological structure and function of brackish and freshwater lakes differ?.- The consequences of a drastic fish stock reduction in the large and shallow Lake Wolderwijd, The Netherlands. Can we understand what happened?.- Trophic interactions in a shallow lake following a reduction in nutrient loading: a long-term study.- Top-down control of phytoplankton in a shallow hypertrophic lake: Little Mere (England).- Food web manipulation in a small eutrophic Lake Wirbel, Poland: effect of stocking with juvenile pike on planktivorous fish.- Environmental effects of introducing whitefish, Coregonus lavaretus (L.), in Lake Ring.- Predator-prey relationships within the pelagic community of Neusiedler See.- Ecological interactions in a shallow sand-pit lake (Lake Créteil, Parisian Basin, France): a modelling approach.- Ecological models and the pitfalls of causality.- Long-term compositional response of phytoplankton in a shallow, turbid environment, Neusiedlersee (Austria/Hungary).- The time course of phytoplankton biomass and related limnological factors in shallow and deep lakes: a multivariate approach.- Long-term phytoplankton changes in a shallow hypertrophie lake, Albufera of Valencia (Spain).- Population dynamics of Limnothrix redekei, Oscillatoria lanceaeformis, Planktothrix agardhii and Pseudanabaena limnetica (Cyanobacteria) in a shallow hypertrophic lake (Spain).- Polymixis of a shallow lake (Grosser Müggelsee, Berlin) and its influence on seasonal phytoplankton dynamics.- Influences of the lowland river Spree on phytoplankton dynamics in the flow-through Lake Müggelsee (Germany).- Relationship between trophic state and plankton community structure in 21 Sicilian dam reservoirs.- Submerged macrophytes in the recently freshened lake system Volkerak-Zoom (The Netherlands), 1987-1991.- The influence of ammonia on the growth and photosynthesis of Ruppia drepanensis Tineo from Doñana National Park (SW Spain).- Colonization and succession of submerged macrophytes in shallow Lake Væng during the first five years following fish manipulation.- Restoration of Botshol (The Netherlands) by reduction of external nutrient load: recovery of a characean community, dominated by Chara connivens.- Nutrient cycling in shallow, oligotrophic Lake Kvie, Denmark. I: Effects of isoetids on the exchange of nitrogen between sediment and water.- Nutrient cycling in shallow, oligotrophic Lake Kvie, Denmark. II: Effects of isoetids on the exchange of phosphorus between sediment and water.- Can Chara control phosphorus cycling in Lake ?uknajno (Poland)?.- Phosphorus fluctuation in water and deposition into sediment within an emergent macrophyte stand.- Benthic-pelagic interactions in shallow water columns: an experimentalist's perspective.- Fish interactions with the sediment-water interface.- The role of zoobenthos in energy flow in two shallow lakes.- Colonization and succession of macroinvertebrates in recently freshened Lake Volkerak-Zoom (The Netherlands).- Nutrient dynamics in shallow lakes: effects of changes in loading and role of sediment-water interactions.- Kinetics of luxury uptake of phosphate by algae-dominated benthic communities.- Nutrient balances and phytoplankton dynamics in two agriculturally loaded shallow lakes.- Effect of summer weather on internal loading and chlorophyll a in a shallow lake: a modeling approach.- Influence of internal loading on phosphorus concentration in shallow lakes before and after reduction of the external loading.- A diatom-phosphorus transfer function for shallow, eutrophic ponds in southeast England.- Recent palaeolimnology of three shallow Danish lakes.- Alum treatment effectiveness and longevity in shallow lakes.- Effects of hypolimnetic water aeration and iron-phosphate precipitation on the trophic level of Lake Krupunder.- The importance of sediment phosphorus release in the restoration of very shallow lakes (The Norfolk Broads, England) and implications for biomanipulation.- Long-term responses to fish-stock reduction in small shallow lakes: interpretation of five-year results of four biomanipulation cases in The Netherlands and Denmark.- Lake Horowhenua: a computer model of its limnology and restoration prospects.- Mathematical modelling as a tool for management in eutrophication control of shallow lakes.- Factors affecting light penetration in shallow lakes.- Water quality management in the River Gudenaa, a Danish lake-stream-estuary system.