Forest Decline and Ozone

Ozone-Exposed Forests Under Euro-American Settlement Influences.- 2.5.4.1 Chronic Ozone Injury and Mortality of Pines Due to Bark Beetle.- 2.5.4.2 Ozone Influences on Recruitment and Mortality of Ponderosa Pine Seedlings.- 2.5.5 Status of Models for Simulating Ozone Effects on Tree Growth and Stand Development.- 2.6 Summary.- References.- 3 Ozone and Its Known and Potential Effects on Forests in Eastern United States.- 3.1 Introduction.- 3.2 Recent Findings from Northeastern Forests.- 3.3 Recent Findings from Northcentral Pennsylvania..- 3.4 Recent Findings from the Shenandoah National Park, Virginia.- 3.5 Recent Findings from Southern United States..- 3.6 Recent Findings from Great Smoky Mountains National Park.- 3.7 General Conclusions.- References.- 4 Ozone and the Forests in Austria and Switzerland.- 4.1 Introduction.- 4.2 O3 Levels and Areas at Risk in the Alps of Central Europe.- 4.3 Tree Responses to O3 Levels at Forest Sites.- 4.3.1 Experimental O3 Exposure of Twigs of Mature Norway Spruce and European Larch Trees in Austrian Forests.- 4.3.1.1 Study Sites, Pollution Load, and Experimental Design.- 4.3.1.2 The Effects of the Various O3 Exposure Regimes.- 4.3.1.3 Stomatal Control of Ozone Uptake.- 4.3.1.4 Detoxification Capacity.- 4.3.2 The Swiss Research Program "Air Pollution and Forest Decline".- 4.3.2.1 Effects of Air Pollutants on the Gas Exchange of Spruce.- 4.3.2.2 Analysis of the Needle Wax Layer, Stem Production, and Fungal Impact.- 4.3.2.3 Experiments on the O3 Sensitivity of Forest Trees.- 4.3.3 Other Field Research on Trees in Switzerland.- 4.4 Mechanisms of O3 Impact on Trees Under Controlled Exposure Conditions.- 4.5 Evidence of O3 Injury on a Regional Scale?.- 4.5.1 Methods of Estimating Forest Condition.- 4.5.2 Spatial Associations Between the Occurrence of Ozone and Crown Conditions.- 4.5.3 Associations of Temporal Trends in O3 Concentration and Crown Condition.- 4.5.4 Is there any Unambiguous Evidence of O3 Injury to Trees in Switzerland and Austria?.- 4.6 Conclusions.- References.- 5 Role of Ozone in Forest Decline on Wank Mountain (Alps).- 5.1 Introduction.- 5.2 Site Characteristics.- 5.2.1 The Bavarian Alps.- 5.2.2 The Wank Mountain Research Site.- 5.2.3 Tree Vitality at the Research Site.- 5.3 Atmospheric Exposure.- 5.4 Soil Characteristics and Tree Nutrition.- 5.5 Physiological Observations.- 5.5.1 Ozone.- 5.5.2 Other Photo-oxidants.- 5.6 Conclusions.- References.- 6 Ozone Responses of Trees: Results from Controlled Chamber Exposures at the GSF Phytotron.- 6.1 Introduction.- 6.2 Chamber Design and Performance.- 6.3 Selected Exposure Experiments.- 6.3.1 Interactions Between Ozone and Acidic Mist.- 6.3.2 Interactions Between Ozone and Carbon Dioxide..- 6.3.3 Effects of Mixtures of Air Pollutants.- 6.4 Biochemical Responses to Ozone.- 6.4.1 Response Levels.- 6.4.2 Photosynthetic Pigments.- 6.4.3 Polyphenolic Metabolites.- 6.4.4 Polyamines and Ethylene.- 6.4.5 Ozone-Related Proteins.- 6.4.6 Lignins.- 6.5 Premature Senescence in Beech.- 6.6 "Memory" Effects for Ozone in Conifers.- 6.7 Conclusions.- References.- 7 Controlled O3 Exposures and Field Observations of 03 Effects in the UK.- 7.1 Introduction.- 7.2 The 03 Climate of the UK.- 7.3 Surveys of Tree Health.- 7.3.1 Sitka Spruce.- 7.3.2 Norway Spruce.- 7.3.3 Scots Pine.- 7.3.4 Oak.- 7.3.5 Beech.- 7.3.6 Ash.- 7.3.7 Yew.- 7.3.8 UN-ECE Surveys.- 7.3.9 The Early Diagnosis Survey.- 7.4 Long-Term Ozone Exposures.- 7.4.1 Filtration Experiments.- 7.4.2 Fumigation Experiments.- 7.4.3 The Liphook Field Exposure Experiment.- 7.5 Ozone-Induced Changes in Epicuticular Waxes.- 7.6 Effects of O3 on Winter Hardiness and Frost Injury.- 7.7 Effects of Ozone on Nutrient Leaching.- 7.8 Effects of Ozone on Photosynthesis and Carbon Allocation.- 7.8.1 Photosynthetic Capacity.- 7.8.2 Carbon Allocation and Utilization.- 7.9 Interactive Effects of Ozone.- 7.9.1 Biotic Factors.- 7.9.2 Water Relations of Deciduous Trees.- 7.10 Conclusions.- References.- 8 Controlled Ozone Exposures and Field Observations in Fennoscandia.- 8.1 Land Use in Fennoscandia.- 8.2 Ozone Concentrations in Fennoscandia.- 8.3 Forest Health.- 8.3.1 Finland.- 8.3.2 Norway.- 8.3.3 Sweden.- 8.3.4 Denmark.- 8.3.5 Resin-Flow Disease in Norway Spruce.- 8.4 Exposure Facilities - Open-Top Chambers and Open-Release Systems.- 8.5 Ozone-Induced Changes in Structure.- 8.5.1 Controlled Exposure Experiments - Conifers.- 8.5.2 Controlled Exposure Experiments - Deciduous Trees.- 8.5.3 Influence of Growth Strategy on Ozone-Induced Structural Changes.- 8.5.4 Field Investigations - Conifers.- 8.5.5 Structural Changes as a Diagnostic Indicator.- 8.6 Ozone-Induced Changes in Gas Exchange.- 8.7 Ozone-Induced Changes in Growth.- 8.8 Conclusions.- References.- 9 Methods for Controlled and Field Ozone Exposures of Forest Tree Species in North America.- 9.1 The Forest and Ozone.- 9.1.1 Progress in Air Pollution Research.- 9.1.2 Limitations to the Application of Crop Research Methods to Forest Ecosystems.- 9.2 Basis for Comparison of Field vs Chamber Research.- 9.2.1 Fumigation Systems - Controlled Environment.- 9.2.2 Fumigation Systems - Field.- 9.2.3 Ambient Gradients.- 9.2.4 Cultivar Comparisons.- 9.2.5 Protective Chemicals.- 9.3 Limitations to Comparisons.- 9.3.1 Scaling Problems.- 9.3.2 Temporal/Spatial Problems.- 9.3.3 Data Analysis.- 9.4 What Is Needed for Future Studies?.- 9.4.1 Biological and Physiological Response.- 9.4.2 Functional Ozone Parameters for Exposure.- 9.4.3 Future Field Research.- 9.5 Summary and Conclusions.- References.- 10 Physiological Processes and Plant Responses to Ozone Exposure.- 10.1 Introduction.- 10.1.1 Air Pollution Injury.- 10.1.1.1 Types of Oxidant Stress.- 10.1.1.2 Overview.- 10.2 The Assault of Air Pollutants upon Plants.- 10.2.1 Sequence of Events Following Air Pollutant Exposure.- 10.2.1.1 Entry of the Pollutant into the Leaf.- 10.2.1.2 Reactions of the Gas Within the Leaf.- 10.2.1.3 Movement of Product(s) and Transformations ..- 10.2.2 Amount of Exposure at the Physiological Level §.- 10.2.2.1 Initial Site of Direct Ozone "Attack".- 10.2.2.2 Ionic Flows Maintained by the Plasma Membrane.- 10.2.3 Responses of Metabolic Processes.- 10.2.3.1 Wounding.- 10.2.3.2 Stress-Induced Alterations in Gene Expression.- 10.2.4 Tissue Level.- 10.2.4.1 Photosynthesis.- 10.2.4.2 Photoinhibition.- 10.2.4.3 Ozone Injury and Carbohydrate Status.- 10.2.4.4 Translocation.- 10.3 Summary of Physiological and Biochemical Events.- 10.3.1 O3 -Induced Changes in the Plant's Ability to Respond to Other Stresses.- 10.4 Role of Models.- 10.4.1 Is an Effect Real?.- 10.5 Conclusion.- References.- 11 Forest Decline and Ozone: Synopsis.- 11.1 Decline Definitions.- 11.2 Ozone History of the Series "Ecological Studies".- 11.3 Decline Potential of Ozone.- 11.4 Ozone and Plant Homeostasis.- 11.5 Types of Injury and Improved Ozone Diagnostics.- 11.6 Population and Ecosystem Responses.- References.- Appendix: Color Illustrations.