Large Lakes

The vast majority of the world's lakes are small in size and short lived in geological terms. Only 253 of the thousands of lakes on this planet have surface areas larger than 500 square kilometers. At first sight, this statistic would seem to indicate that large lakes are relatively unimportant on a global scale; in fact, however, large lakes contain the bulk of the liquid surface freshwater of the earth. Just Lake Baikal and the Laurentian Great Lakes alone contain more than 38% of the world's total liquid freshwater. Thus, the large lakes of the world accentuate an important feature of the earth's freshwater reserves-its extremely irregular distribution. The energy crisis of the 1970s and 1980s made us aware of the fact that we live on a spaceship with finite, that is, exhaustible resources. On the other hand, the energy crisis led to an overemphasis on all the issues concerning energy supply and all the problems connected with producing new energy. The energy crisis also led us to ignore strong evidence suggesting that water of appropriate quality to be used as a resouce will be used up more quickly than energy will. Although in principle water is a "renewable resource," the world's water reserves are diminishing in two fashions, the effects of which are multiplicative: enhanced consumption and accelerated degradation of quality.

1 Introduction. - 1 Distribution of the World s Large Lakes. - 2 Specific Properties of Large Lakes. - 2 Physical Features of Large Lakes and Their Significance for Biological Processes. - 3 Mixing and Transport in Lakes: Mechanisms and Ecological Relevance. - 4 On Internal Seiches and Noisy Current Fields Theoretical Concepts Versus Observations. - 5 Long-Term Modelling of Stratification in Large Lakes: Application to Lake Constance. - 6 Spring Mixing Depth as a Determinant of Annual Primary Production in Lakes. - 7 Behavior of a Medium-Sized Basin Connected to a Large Lake. - 8 Effects of Water Level Fluctuation on the Structure and Function of the Littoral Zone. - 3 Particle Transport and Chemical Fluxes. - 9 Horizontal Transport and Sedimentation by Interflows and Turbidity Currents in Lake Geneva. - 10 Significance of Sediment Resuspension and Particle Settling. - 11 Time Scales of Sediment Focusing in Large Lakes as Revealed by Measurement of Fallout Cs-137. - 12 Characterizing Autochthonous Iron Particles and Colloids the Need for Better Particle Analysis Methods. - 13 Pathways and Residence Times of Radiotracers in Lake Constance. - 14 Biological Transfer and Sedimentation of Chernobyl Radionuclides in Lake Constance. - 15 Lacustrine Carbonates as Geochemical Archives of Environmental Change and Biotic/Abiotic Interactions. - 16 Sedimentation and Eutrophication History of Austrian Alpine Lakes. - 4 Production, Periodicity, and Distribution of the Plankton. - 17 Environmental and Physiological Control of Phytoplankton Productivity in Large Lakes. - 18 Effects of Latitude on Phytoplankton Composition and Abundance in Large Lakes. - 19 Relationship of Phytoplankton and Nutrients to Stoichiometric Measures. - 20 Ecology of Melosira Species in the Great Lakes of Africa. - 21Cyanobacteria in Large Lakes: A Case Study in Lake Constance. - 22 Patterns in Zooplankton Distribution and Their Causes in North American Great Lakes. - 23 Seasonal Succession of Rotifers in Large Lakes. - 5 Food-Web Structures and Trophic Interactions. - 24 Bacterial Cycling of Matter in the Pelagic Zone of Aquatic Ecosystems. - 25 Bacterial Production and the Flow of Organic Matter in Lake Constance. - 26 Seasonal Changes in Methane, Hydrogen, and Carbon Monoxide Concentrations in a Large and a Small Lake. - 27 Microbial Food-Webs and Nutrient Cycling in Lakes: Changing Perspectives. - 28 Contribution of Picoplankton to the Grazer Food Chain of Lake Biwa. - 29 Significance of Heterotrophic Nanoflagellates and Ciliates in Large Lakes: Evidence from Lake Constance. - 30 On Pelagic Food Web Interactions in Large Water Bodies. - 31 Lake Trophic Status and the Development of the Clear-Water Phase in Lake Geneva. - 32 Impact of Zooplankton Grazing on Phytoplankton Along a Trophic Gradient. - 33 Strength of Zooplankton-Phytoplankton Coupling in Relation to Lake Trophic State. - 34 Pontoporeia hoyi a Direct Trophic Link between Spring Diatoms and Fish in Lake Michigan. - 35 Fish Predation Effects on Plankton Community Structure in Large Lakes: Lake Kinneret. - 6 Ecological Structure and Function in Large Lakes. - 36 Overview: An Appraisal of Concepts.