Disturbance and Ecosystems

Section 1 Biosphere.- 1.1 The Blue Planet: of Wholes and Parts and Man.- 1.1.1 Introduction.- 1.1.2 The CO2 Problem.- 1.1.3 Toxification.- 1.1.4 The Effects: Biotic Impoverishment.- 1.1.5 Conclusions.- Résumé.- References.- Section 2 Landscape.- 2.1 Landscape Modification and Changing Ecological Characteristics.- 2.1.1 Ecosystems and Landscapes.- 2.1.2 Some Ecological Attributes for Comparing Landscapes.- 2.1.2.1 Horizontal Structure.- 2.1.2.2 Stability.- 2.1.2.3 Thermodynamic Characterization.- 2.1.2.4 Chorology.- 2.1.2.5 Minimal Area (or Grain).- 2.1.2.6 Nutrient Cycling.- 2.1.2.7 Net Production.- 2.1.2.8 Tactics.- 2.1.2.9 Phylogeny.- 2.1.2.10 Type of Resistance.- 2.1.2.11 Conclusion.- 2.1.3 Disturbance Regimes.- 2.1.4 Effect on Landscape Patch Structure.- 2.1.4.1 Patch Origins.- 2.1.4.2 Patch Size.- 2.1.4.3 Patch Shape.- 2.1.4.4 Patch Numbers and Configuration.- 2.1.4.5 Summary for Patch Trends.- 2.1.5 Effect of Linkage Characteristics of the Landscape.- 2.1.5.1 Line Corridors.- 2.1.5.2 Strip Corridors.- 2.1.5.3 Stream Corridors.- 2.1.5.4 Networks.- 2.1.5.5 Habitations.- 2.1.5.6 Matrix.- 2.1.5.7 Summary of Trends for Linkage Characteristics.- 2.1.6 Conclusions.- Résumé.- References.- 2.2 Ecological Modeling of Landscape Dynamics.- 2.2.1 Introduction.- 2.2.2 Approaches to Modeling Landscape Dynamics.- 2.2.3 A Differential Equation Model of Landscape Change.- 2.2.4 Complex Digital Computer Model of Forest Dynamics.- 2.2.5 Evaluating the Impact of Regional Scale Problems on Localized Stands.- 2.2.6 Evaluating Impact of Regional Scale Problems Across Landscapes.- 2.2.7 Future Directions in Simulation Analysis of Landscapes.- 2.2.8 Conclusions.- Résumé.- References.- Section 3 Ecosystem Functions.- 3.1 Research on the Characteristics of Energy Flows within Natural and Man-Altered Ecosystems.- 3.1.1 Introduction.- 3.1.2 Examples of Energy Flows in Selected Ecosystems.- 3.1.3 Primary Production.- 3.1.3.1 Effect of Rejuvenating Forest Stands.- 3.1.3.2 Effect of Cutting on the Production of Grasslands.- 3.1.3.3 Effect of Grazing.- 3.1.3.4 Effects of Fire on Grasslands.- 3.1.3.5 Destruction and Transformation of Wooded Areas.- 3.1.4 Diversity of Energy Flows in Animal Populations.- 3.1.4.1 A/I Assimilation Efficiency.- 3.1.4.2 P/A Tissue Growth Efficiency.- 3.1.4.3 P/I Ecological Efficiency.- 3.1.4.4 Possibility of Changing the Energy-use Efficiency at the Individual Level.- 3.1.4.5 Possibility of Changing the Energy-use Efficiency of Populations.- 3.1.5 Conclusions.- Résumé.- References.- 3.2 “Natural” Mixed Forests and “Artificial” Monospecific Forests.- 3.2.1 Introduction.- 3.2.2 Advantages of Mixed Forests.- 3.2.3 The Yield of Mixtures.- 3.2.4 Economic Considerations.- 3.2.5 Conclusions — Research on Mixed Forests.- Résumé.- References.- 3.3 Disturbance and Basic Properties of Ecosystem Energetics.- 3.3.1 Introduction.- 3.3.2 Biomass and Energy Flow in Infrequently Disturbed Ecosystems.- 3.3.2.1 Net Primary Production and Energy Flow Pathways.- 3.3.2.2 Biomass and Detritus Accumulation.- 3.3.2.3 Net Ecosystem Production.- 3.3.2.4 Variation in Infrequent Disturbance Events.- 3.3.3 Biomass and Energy Flow in Multiple Disturbance Ecosystems.- 3.3.3.1 Constant Species Composition and Site Quality.- 3.3.3.2 Changing Ecosystem Structure with Disturbance Frequency.- 3.3.4 Conclusions: Integration.- Résumé.- References.- 3.4 Ecosystem Water Balance.- 3.4.1 Basic Concepts.- 3.4.1.1 Water Budgeting.- 3.4.1.2 Energy Budgeting.- 3.4.1.3 Practical Limitations.- 3.4.2 Ecosystem Influences.- 3.4.2.1 Gross Precipitations.- 3.4.2.2 Evaporation Losses.- 3.4.2.3 Discharge Losses.- 3.4.3 Human Influences.- 3.4.3.1 Major Disturbances.- 3.4.3.2 Flow Regimes.- 3.4.3.3 Miscellaneous Influences.- 3.4.4 Conclusions.- Résumé.- References.- 3.5 Some Problems of Disturbance on the Nutrient Cycling in Ecosystems.- 3.5.1 Introduction.- 3.5.2 Fire.- 3.5.3 Reforestation by Conifers.- 3.5.4 Forest Fertilization.- 3.5.5 Removal of Forest Products.- 3.5.6 The Mineral Budget and Plant Succession.- 3.5.7 Conclusions.- Résumé.- References.- 3.6 Mechanisms of Ion Leaching in Natural and Managed Ecosystems.- 3 6.1 Introduction.- 3.6.2 Leaching of Anions and Cations.- 3.6.2.1 Measurement of Leaching Losses.- 3.6.2.2 Leaching Mechanisms — Anion Mobility.- 3.6.2.3 The Major Anions.- 3.6.2.4 Effects of Management Practices on Nitrate Fluxes.- 3.6.2.5 Leaching Losses in Other Biomes.- 3.6.3 Conclusions.- Résumé.- References.- Section 4 Species Physiological Characteristics.- 4.1 The Determinants of Plant Productivity — Natural Versus Man-Modified Communities.- 4.1.1 Introduction.- 4.1.2 Comparisons of Productivity.- 4.1.3 The Components of Plant Productivity.- 4.1.3.1 The Biotic Component.- 4.1.3.2 Environmental Influences on the Biological Components of Productivity.- 4.1.3.3 Interactions of Productivity Components and Resource Level in Natural Communities.- 4.1.4 Succession and Plant Productivity.- 4.1.5 Succession Anomalies.- 4.1.6 Convergence in Productivity.- 4.1.7 Agricultural Versus Natural Community Productivity.- 4.1.8 Conclusions.- Résumé.- References.- 4.2 Plant Growth and Its Limitations in Crops and Natural Communities.- 4.2.1 Introduction.- 4.2.2 Plant Growth Parameters.- 4.2.2.1 Photosynthesis.- 4.2.2.2 Respiration.- 4.2.2.3 Other Growth Processes.- 4.2.3 Comparison of Cultivated and Wild Species.- 4.2.3.1 The Case of Wheat.- 4.2.3.2 Adaptation of Natural Species to a Given Level of Resources.- 4.2.4 Crops Versus Natural Communities.- 4.2.5 Towards an Estimate in the Level of Available Resources.- 4.2.5.1 Light.- 4.2.5.2 Water.- 4.2.5.3 Nutrients.- 4.2.6 Conclusions.- Résumé.- References.- 4.3 Patterns of Nutrient Absorption and Use by Plants from Natural and Man-Modified Environments.- 4.3.1 Introduction.- 4.3.2 General Patterns and Nutrient Use.- 4.3.3 Successional Changes in Nutrient Use.- 4.3.4 Nutritional Patterns Related to Disturbance.- 4.3.4.1 Abandoned Fields.- 4.3.4.2 Post-Fire Succession.- 4.3.4.3 Tundra Disturbance.- 4.3.4.4 Disturbances Causing Reduced Nutrient Availability.- 4.3.5 Conclusions.- Résumé.- References.- 4.4 Comparisons of Water Balance Characteristics of Plant Species in “Natural” Versus Modified Ecosystems.- 4.4.1 Introduction.- 4.4.2 Theoretical Background.- 4.4.2.1 Heat and Water Exchange Processes.- 4.4.2.2 Water Availability and Plant Characteristics.- 4.4.3 Survey of Plant Characteristics.- 4.4.3.1 General Relations.- 4.4.3.2 Factors and Processes Affecting Water Loss.- 4.4.3.3 Factors and Processes Affecting Water Uptake.- 4.4.3.4 State of Water in the Plant.- 4.4.3.5 Growth and Death in Relation to Plant Water Content.- 4.4.4 Theoretical Considerations Relating Plant Characteristics and Successional State.- 4.4.4.1 Water Availability and Vegetative Recivery in the Semiarid Mediterranean Regions of Southern California.- 4.4.5 Conclusions.- Résumé.- References.- Section 5 Population Characteristics.- 5.1 Reproductive Strategies and Disturbance by Man.- 5.1.1 Introduction.- 5.1.2 Chemical and Sexual Polymorphism in Thyme.- 5.1.2.1 Sexual Polymorphism.- 5.1.2.2 Chemical Polymorphism.- 5.1.2.3 Environment and Population Genetic Structure.- 5.1.3 Enzymatic Polymorphism in Orchard Grass.- 5.1.4 Conclusions.- Résumé.- References.- 5.2 Demographic Strategies and Originating Environment.- 5.2.1 Introduction.- 5.2.2 Description of the Originating Environments.- 5.2.3 Between and Within-Population Variations of Strategies in Arrhenatherum elatius.- 5.2.4 Between and Within-Population Variations of Strategies in D. glomerata.- 5.2.5 Conclusions.- References.- 5.3 Genetic Characteristic of Populations.- 5.3.1 Introduction.- 5.3.2 Population Studies in Avena spp.- 5.3.3 Rose Clover, a Case History of Recent Colonization.- 5.3.4 Population Dynamics of Species in a Coastal Grassland Ecosystem.- 5.3.5 Variation and Colonization Success of Crop-Weed Hybrids.- 5.3.6 Alternative Strategies of Colonizing Success.- 5.3.7 Evolutionary Genetics of Adaptive Responses.- 5.3.8 Recombination Properties of Genetic Systems.- 5.3.9 Interspecific Interactions in Community Dynamics.- 5.3.10 Conclusions.- Résumé.- References.- 5.4 Characteristics of Populations in Relation to Disturbance in Natural and Man-Modified Ecosystems.- 5.4.1 Introduction.- 5.4.2 The Nature of Disturbance.- 5.4.3 Disturbance Characteristic with Relevance to Population Response.- 5.4.3.1 Size.- 5.4.3.2 Frequency of Occurrence.- 5.4.3.3 Intensity.- 5.4.3.4 Time of Disturbance.- 5.4.3.5 Level of Environmental Heterogeneity.- 5.4.3.6 Nature of the Biologic Neighborhood.- 5.4.4 Population Characteristics Responsive to Disturbance.- 5.4.4.1 Density, Dispersion and Age Structure.- 5.4.4.2 Genotypic Variability in Populations.- 5.4.4.3 Interactions Between Species.- 5.4.5 Life History Characteristics and Disturbance.- 5.4.5.1 Life Span.- 5.4.5.2 Reproductive Strategies.- 5.4.5.3 Germination, Growth and Response Breadth.- 5.4.6 Conclusions.- Résumé.- References.