The Ecology of Tropical Lakes and Rivers

Transcription

1 The Ecology of Tropical Lakes and Rivers A. I. Payne Coventry {Lanchester) Polytechnic JOHN WILEY & SONS Chichester New York Toronto Brisbane Singapore

2 Contents 1 INTRODUCTION 1 2 THE RIVER ENVIRONMENT Characteristics of the Water 4. 1 The Concentration of Surface Waters 4.2* The Measurement of Ionic Concentration Bicarbonate and Carbonate 5.4 Concentration and Composition of Tropical and Temperate Waters 7.5 Sources of Major Chemical Components 7.6 Possible Role of Rain, Rocks, and Evaporation in Determining the Composition of Tropical River Water Water and Land in a River Basin Soil and Vegetation Swamps, Floodplains, and Phytoplankton The Influence of Animals Suspended Materials Variability of Tropical Rivers Geographical Seasonal 20 THE LAKE ENVIRONMENT Characteristics of Lakes Size and Formation Water Loss and Gain High-altitude Lakes General Distribution Hydrology and Water Budgets Routes of Gain and Loss Periodic Changes Seasonal Changes Chemical Environment Ionic Concentration Ionic Composition Classification of Lakes Stratification and its Effects General Features Effect on Physical and Chemical Factors Multiple Thermoclines Importance of Mixing Shallow Lakes 47

3 VI 4 COMMUNITY STRUCTURE Basic Organization Types and Distribution of Organisms in Aquatic Communities Structure in Lakes and Rivers Qualitative and Quantitative Considerations The Phytoplankton Algae Large and Small Composition 58 (a) Bacillariophyta 58 (b) Chlorophyta 60 (c) Dinophyta 60 (d) Cyanobacteria (Cyanophyta) 60 (e) Others Weight and Numbers 62 (a) Sampling 62 (b) How much Phytoplankton in tropical waters? Maintaining a Position Zooplankton 68 4.b. 1 Composition and Characteristics Feeding Reproduction Weight and Numbers 72 (a) Sampling 72 (b) Zooplankton biomass in the tropics Vertical Distribution and Diurnal Migration The Benthos Composition Feeding Sampling Biomass and Assemblages in Natural and Man-made Lakes Biomass and Assemblages in Flowing Waters The Nekton Composition River Fishes Fish in Lakes Littoral and Surface Vegetation Composition ' Littoral Vegetation '.. Ill Plants of the Water Surface Vegetation of Rivers Biomass Community Structure and the Distribution of Biomass General Reading COMMUNITY DYNAMICS The Basis of Production Primary Production Light The Measurement of Primary Production (a) Light and dark bottle oxygen method 127 (b) Light and dark 14 C method 129 (c) Oxygen flux in a whole water body 130 (d) The use of satellite photography 131

4 5.2.3 Patterns of Productivity 131 (a) Lakes 131 (b) Rivers 140 (c) Swamps and marginal vegetation Nutrient Recycling 146 (a) Which nutrients limit photosynthesis? (b) The distribution of nutrients Microbial Activity and Decomposition Secondary Production Feeding Relationships Some Effects of Grazing Rates of Production 159 (a) Zooplankton (b) Benthic animals 160 (c) Fish Energy Flow Within the Ecosystem 164 General Reading. 168 Vll SEASONALITY Are There Seasons in the Tropics? The Phenology of Production Seasonal Versus Daily Changes in Production Animal Periodicity Seasonal Factors in Flowing Waters Feeding and Food Availability Reproduction 182 (a) Rivers 182 (b) Lakes DIVERSITY AND EVOLUTION How Diverse are Communities in Tropical Fresh Waters? General Considerations The Producers The Zooplankton Benthic Organisms Some are Less Diverse Than Others The Meaning of Diversity The Relationship of Diversity to Production and Time Coexistence in a Crowded Environment Sources of Diversity Stability and Change 223 General Reading 231 THE USE AND CONTROL OF AQUATIC BIOLOGICAL RESOURCES Man and Water Fisheries The Basis of Production and the Prediction of Yields Fishery Management The Introduction of Exotic Species Aquaculture 248

5 Vlll 8.4 Pollution 8.5 Health General Reading 270 BIBLIOGRAPHY 271 INDEX 290