Contaminants in Terrestrial Environments

Defining ecology as a system-theory oriented synthesis of both earth and life sciences, the book aims at a novel co- herent understanding of chemicalimpact on the lower at- mosphere and characteristic types of terrestrial ecosystems. To this end comprehensive flux-analytical and hierarchical modelling approaches were developed and consulted, which in- clude a thorough consideration of the specific physical and geographic boundary conditions of the processes involved. The first part is devoted to fundamentals of environmental chemistry and ecology, while the second deals with the com- plex atmospheric pathways of anthropogenic chemicals. In the last part, the manifold interactions of these compounds or their metabolites with the soil-vegetation complex of eco- systems are described. Chapters on pollutant impact on mate- rials and a review of chemical fate modelling are included. Thus scientists and practitioners facing ecological projects may expect to obtain a deeper insight into landscape ecology from the impact point of view owing to the concise presenta- tion of complex mechanisms and the generalized modelling ap- proach.

1 Introduction.- 1.1 Man and Environment.- 1.2 Technical Chemistry and Ecology.- 2 Basic Chemical and Ecological Principles.- 2.1 Exposure and Effect Criteria of Chemicals.- 2.1.1 Structure—Activity Relationships.- 2.1.1.1 Chemical Structure Descriptors.- 2.1.1.2 Techniques for Defining Structure—Activity Relationships.- 2.1.2 Equilibrium Constants for Chemicals Distribution..- 2.1.2.1 Aggregate State and Related Properties.- 2.1.2.2 Specific Gravity, Molar Mass and Structure.- 2.1.2.3 Melting and Boiling Points.- 2.1.2.4 Vapour Pressure, Vapour Density and Volatility.- 2.1.2.5 Water Solubility.- 2.1.2.6 n-Octanol/Water Partition Coefficient.- 2.1.3 Kinetic Constants for Environmental Processes.- 2.1.3.1 Hydrolysis.- 2.1.3.2 Photolysis.- 2.1.3.3 Oxidation and Reduction.- 2.1.3.4 Biotransformation.- 2.1.3.5 Bioconcentration, Bioaccumulation and Ecological Magnification.- 2.2 Stability of Ecosystems.- 2.2.1 Different Notions of Stability.- 2.2.2 Stability and Diversity of Ecological Communities.- 2.2.2.1 Diversity Analyses.- 2.2.2.2 Ecological Communities as Dissipative Structures.- 2.3 Biota Resilience Versus Chemical Persistence.- 2.3.1 Chemical Persistence.- 2.3.2 Resilience of Natural Biota.- 2.4 Model Ecosystems and Related Definitions of Environmental Toxicity of Chemicals.- 2.4.1 Eco toxicological Tests.- 2.4.2. Comparative Appraisal and Research Needs.- 3 Fluxes of Anthropogenic Chemicals in the Atmosphere.- 3.1 Natural and Anthropogenic Sources of Potential Pollutants.- 3.1.1 Natural Atmospheric Cycles.- 3.1.2. Anthropogenic Air Pollution.- 3.2 Transport and Dispersion.- 3.2.1 General Atmospheric Boundary Conditions of Air Pollution.- 3.2.2 Atmospheric Lapse Rates and Plume Dilution.- 3.2.3 Selected Dispersion Models.- 3.2.3.1 Box Models.- 3.2.3.2 Statistical Models.- 3.2.3.3 Gaussian Dispersion Models.- 3.2.3.4 Grid Models.- 3.2.3.5 Trajectory Models.- 3.3 Physical Transformation Processes.- 3.3.1 Nucleation.- 3.3.2 Coagulation.- 3.3.3 Condensation.- 3.3.4 Rainout and Washout.- 3.4 Chemical Transformation Processes.- 3.4.1 Formation of Free Radicals and Reactive Trace Constituents.- 3.4.2 Sulphate Reactions.- 3.4.3 Nitrate-Forming Reactions.- 3.4.4 Oxidative Chemistry of Organic Pollutants.- 3.4.4.1 Atmospheric Reaction Pathways for Alkanes.- 3.4.4.2 Atmospheric Reaction Pathways for Alkenes.- 3.4.4.3 Atmospheric Chemistry of Aromatics.- 3.5 Deposition.- 3.5.1 Deposition Networks.- 3.5.2 Sampling Procedures.- 3.5.3 Principles of Deposition.- 3.5.3.1 Dry Deposition of Gases.- 3.5.3.2 Dry Deposition of Particles.- 3.5.3.3 Model Concept of Deposition.- 3.5.4 Deposition of Gases.- 3.5.4.1 General Features of Deposition.- 3.5.4.2 Deposition of Acidic Species and Ozone.- 3.5.5 Removal of Air-Borne Metals by Wet and Dry Deposition.- 3.5.5.1 Factors Influencing Total Atmospheric Deposition of Metals.- 3.5.5.2 Deposition Rates and Mechanisms in Deciduous and Coniferous Forests.- 3.5.5.3 Microscale Variability of Deposition in Forests.- 3.5.5.4 Large-Scale Spatial Variability of Atmospheric Removal Processes of Air-Borne Metals.- 3.5.5.5 Deposition Velocities of Metals.- 3.5.6 Deposition Patterns of Hydrocarbons.- 3.5 7 Deposition of Air-Borne Dust.- 4 Fluxes of Chemicals in the Soil—Vegetation Complex.- 4.1 Energy and Water Balances as Boundary Conditions of Chemical Fluxes.- 4.1.1 Energy Balance at the Earth’s Surface.- 4.1.1.1 Net Radiation.- 4.1.1.2 Soil Heat Flow.- 4.1.1.3 Sensible Heat Flow in the Lower Atmosphere.- 4.1.1.4 Latent Heat Flux.- 4.1.1.5 Efficiency of Photosynthesis.- 4.1.1.6 Energy Balance of Wet, Dry and Vegetated Surfaces.- 4.1.2 Water Balance of Bare Soil and Vegetation Stands.- 4.1.2.1 Precipitation and Interception.- 4.1.2.2 Infiltration and Surface Runoff.- 4.1.2.3 Deep Drainage.- 4.1.2.4 Change in Soil Water Storage.- 4.1.2.5 Soil Water Potential and Matrix Flow.- 4.2 Impact of Environmental Chemicals on Vegetation.- 4.2.1 Direct Effects of Acid and Basic Deposition and Photo-Chemical Oxidants.- 4.2.1.1 Sulphur Dioxide.- 4.2.1.2 Nitrogen Oxides.- 4.2.1.3 Ammonia.- 4.2.1.4 Photooxidants.- 4.2.1.5 Combined Effects of Pollutant Gases.- 4.2.1.6 Particulate Pollutants.- 4.2.1.7 Combination Effects of Acid Precipitation.- 4.2.2 Indirect Effects of Acidic Precipitation.- 4.2.2.1 Biotic Interactions.- 4.2.2.2 Interactions with Pesticides.- 4.2.2.3 Soil Acidification and Related Effects on Soil-Borne Microorganisms.- 4.2.3 Dynamic Models of Forest Dieback.- 4.2.3.1 Models with Non-Linear Dose-Effect Relationships.- 4.2.3.2 Time-Series Analysis and Mapping.- 4.3 Pollutant Impact on Materials.- 4.3.1 Pollutant Effects.- 4.3.1.1 Corrosion of Metals and Metal Alloys.- 4.3.1.2 Degradation of Inorganic Non-Metallic Materials.- 4.3.1.3 Degradation of Organic Materials.- 4.3.2 Critical Levels of Pollution.- 4.3.3. European Research Programmes on Pollutants Effects and Restoration.- 4.4 Interactions of Environmental Chemicals with Soil and Subsoil.- 4.4.1 Environmental Factors and Chemistry.- 4.4.1.1 Dispersion.- 4.4.1.2 Sorption and Ion Exchange.- 4.4.1.3 Heavy Metals and Organics in Soil.- 4.4.2 Bioavailability and Biotransformation.- 4.4.2.1 Effects of Chemicals on Microorganisms and Soil Fauna.- 4.4.2.2 Chemical Structure and Biodegradation.- 4.4.2.3 Active Microorganisms.- 4.4.3 Chemical Fate Modelling.- 4.4.3.1 Transport Modelling of Dissolved Chemicals.- 4.4.3.2 Immiscible Contaminant Modelling.- 4.4.3.3 Aquatic Equilibrium Modelling.- 4.4.3.4 Regionalized Fate Modelling.- References.