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Preface | |
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The Soils Around Us | |
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Functions of Soils in Our Ecosystem | |
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Medium for Plant Growth | |
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Regulator of Water Supplies | |
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Recycler of Raw Materials | |
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Habitat for Soil Organisms | |
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Engineering Medium | |
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Soil as Environmental Interface | |
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Soil as a Natural Body | |
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The Soil Profile and Its Layers (Horizons) | |
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Topsoil and Subsoil | |
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Soil: The Interface of Air, Minerals, Water, and Life | |
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Mineral (Inorganic) Constituents of Soils | |
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Soil Organic Matter | |
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Soil Water: A Dynamic Solution | |
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Soil Air: A Changing Mixture of Gases | |
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Interaction of Four Components to Supply Plant Nutrients | |
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Nutrient Uptake by Plant Roots | |
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Soil Quality, Degradation, and Resilience | |
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Conclusion | |
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Study Questions | |
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References | |
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Formation of Soils from Parent Materials | |
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Weathering of Rocks and Minerals | |
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Physical Weathering (Disintegration) | |
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Biogeochemical Weathering | |
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Factors Influencing Soil Formation | |
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Parent Materials | |
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Residual Parent Material | |
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Colluvial Debris | |
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Alluvial Stream Deposits | |
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Marine Sediments | |
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Parent Materials Transported by Glacial Ice and Meltwaters | |
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Parent Materials Transported by Wind | |
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Organic Deposits | |
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Climate | |
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Biota: Living Organisms | |
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Topography | |
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Time | |
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Four Basic Processes of Soil Formation | |
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The Soil Profile | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Classification | |
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Concept of Individual Soils | |
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Comprehensive Classification System: Soil Taxonomy | |
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Categories and Nomenclature of Soil Taxonomy | |
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Soil Orders | |
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Entisols (Recent: Little If Any Profile Development) | |
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Inceptisols (Few Diagnostic Features: Inception of B Horizon) | |
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Andisols (Volcanic Ash Soils) | |
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Gelisols (Permafrost and Frost Churning) | |
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Histisols (Organic Soils without Permafrost) | |
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Aridisols (Dry Soils) | |
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Vertisols (Dark, Swelling and Cracking Clays) | |
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Mollisols (Dark, Soft Soils of Grasslands) | |
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Alfisols (Argillic or Natric Horizon, Medium to High Bases) | |
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Ultisols (Argillic Horizon, Low Bases) | |
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Spodosols (Acid, Sandy, Forest Soils, Low Bases) | |
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Oxisols (Oxic Horizon, Highly Weathered) | |
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Lower-Level Categories in Soil Taxonomy | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Architecture and Physical Properties | |
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Soil Color | |
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Soil Texture (Size Distribution of Soil Particles) | |
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Soil Textural Classes | |
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Structure of Mineral Soils | |
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Soil Density | |
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Pore Space of Mineral Soils | |
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Formation and Stabilization of Soil Aggregates | |
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Tillage and Structural Management of Soils | |
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Soil Properties Relevant to Engineering Uses | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Water: Characteristics and Behavior | |
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Structure and Related Properties of Water | |
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Capillary Fundamentals and Soil Water | |
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Soil Water Energy Concepts | |
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Soil Water Content and Soil Water Potential | |
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The Flow of Liquid Water in Soil | |
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Infiltration and Percolation | |
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Water Vapor Movement in Soils | |
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Qualitative Description of Soil Wetness | |
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Factors Affecting Amount of Plant-Available Soil Water | |
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Mechanisms by Which Plants Are Supplied with Water | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil and the Hydrologic Cycle | |
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The Global Hydrologic Cycle | |
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Fate of Precipitation and Irrigation Water | |
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The Soil-Plant-Atmosphere Continuum | |
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Efficiency of Water Use | |
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Control of Evapotranspiration (ET) | |
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Control of Surface Evaporation (E) | |
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Liquid Losses of Water from the Soil | |
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Percolation and Groundwaters | |
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Enhancing Soil Drainage | |
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Septic Tank Drain Fields | |
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Irrigation Principles and Practices | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Aeration and Temperature | |
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Soil Aeration--The Process | |
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Means of Characterizing Soil Aeration | |
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Oxidation-Reduction (Redox) Potential | |
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Factors Affecting Soil Aeration | |
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Ecological Effects of Soil Aeration | |
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Aeration in Relation to Soil and Plant Management | |
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Wetlands and Their Poorly Aerated Soils | |
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Processes Affected by Soil Temperature | |
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Absorption and Loss of Solar Energy | |
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Thermal Properties of Soils | |
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Soil Temperature Control | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Colloids: Seat of Soil Chemical and Physical Activity | |
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General Properties and Types of Soil Colloids | |
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Fundamentals of Layer Silicate Clay Structure | |
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Mineralogical Organization of Silicate Clays | |
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Structural Characteristics of Nonsilicate Colloids | |
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Genesis and Geographic Distribution of Soil Colloids | |
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Sources of Charges on Soil Colloids | |
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Adsorption of Cations and Anions | |
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Cation Exchange Reactions | |
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Cation Exchange Capacity | |
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Exchangeable Cations in Field Soil | |
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Anion Exchange | |
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Sorption of Pesticides and Groundwater Contamination | |
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Binding of Biomolecules to Clay and Humus | |
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Physical Implications of Swelling-Type Clays | |
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Environmental Uses of Swelling-Type Clays | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Acidity | |
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The Process of Soil Acidification | |
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Role of Aluminum in Soil Acidity | |
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Pools of Soil Acidity | |
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Buffering of pH in Soils | |
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Determination of Soil pH | |
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Human-Influenced Soil Acidification | |
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Biological Effects of Soil pH | |
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Raising Soil pH by Liming | |
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Alternative Ways to Ameliorate the III Effects of Soil Acidity | |
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Lowering Soil pH | |
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Calcium and Magnesium as Plant Nutrients | |
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Conclusion | |
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Study Questions | |
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References | |
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Soils of Dry Regions: Alkalinity, Salinity, and Sodicity | |
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Causes of Alkalinity: High Soil pH | |
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Characteristics and Problems of Alkaline Soils | |
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Development of Salt-Affected Soils | |
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Measuring Salinity and Sodicity | |
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Classes of Salt-Affected Soils | |
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Growth of Plants on Salt-Affected Soils | |
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Water-Quality Considerations for Irrigation | |
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Reclamation of Saline Soils | |
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Reclamation of Saline-Sodic and Sodic Soils | |
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Management of Reclaimed Soils | |
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Conclusion | |
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Study Questions | |
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References | |
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Organisms and Ecology of the Soil | |
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The Diversity of Organisms in the Soil | |
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Organisms in Action | |
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Organism Abundance, Biomass, and Metabolic Activity | |
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Earthworms | |
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Ants and Termites | |
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Soil Microanimals | |
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Roots of Higher Plants | |
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Soil Algae | |
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Soil Fungi | |
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Soil Bacteria | |
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Soil Actinomycetes | |
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Conditions Affecting the Growth of Soil Microorganisms | |
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Beneficial Effects of Soil Organisms | |
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Soil Organisms and Damage to Higher Plants | |
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Ecological Relationships Among Soil Organisms | |
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Genetically Engineered Microorganisms | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Organic Matter | |
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The Global Carbon Cycle | |
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The Process of Decomposition in Soils | |
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Factors Controlling Rates of Decomposition and Mineralization | |
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Humus: Genesis and Nature | |
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Composts and Composting | |
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Direct Influences of Organic Matter on Plant Growth | |
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Influence of Organic Matter on Soil Properties and the Environment | |
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Management of Amount and Quality of Soil Organic Matter | |
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Carbon Balance in the Soil-Plant-Atmosphere System | |
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Factors and Practices Influencing Soil Organic Matter Levels | |
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Soils and the Greenhouse Effect | |
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Organic Soils (Histosols) | |
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Conclusion | |
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Study Questions | |
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References | |
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Nitrogen and Sulfur Economy of Soils | |
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Influence of Nitrogen on Plant Growth and Development | |
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Origin and Distribution of Nitrogen | |
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The Nitrogen Cycle | |
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Immobilization and Mineralization | |
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Soluble Organic Nitrogen | |
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Ammonium Fixation by Clay Minerals | |
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Ammonia Volatilization | |
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Nitrification | |
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The Nitrate Leaching Problem | |
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Gaseous Losses by Denitrification | |
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Biological Nitrogen Fixation | |
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Symbiotic Fixation with Legumes | |
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Symbiotic Fixation with Nonlegumes | |
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Nonsymbiotic Nitrogen Fixation | |
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Addition of Nitrogen to Soil in Precipitation | |
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Reactions of Nitrogen Fertilizers | |
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Practical Management of Soil Nitrogen in Agriculture | |
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Importance of Sulfur | |
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Natural Sources of Sulfur | |
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The Sulfur Cycle | |
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Behavior of Sulfur Compounds in Soils | |
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Sulfur Oxidation and Reduction | |
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Sulfur Retention and Exchange | |
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Sulfur and Soil Fertility Maintenance | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Phosphorus and Potassium | |
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Role of Phosphorus in Plant Nutrition and Soil Fertility | |
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Effects of Phosphorus on Environmental Quality | |
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The Phosphorus Cycle | |
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Organic Phosphorus in Soils | |
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Inorganic Phosphorus in Soils | |
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Solubility of Inorganic Phosphorus in Acid Soils | |
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Inorganic Phosphorus Availability at High pH Values | |
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Phosphorus-Fixation Capacity of Soils | |
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Plant Genetics and Phosphorus Availability | |
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Practical Control of Phosphorus in Soils | |
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Potassium: Nature and Ecological Roles | |
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Potassium in Plant and Animal Nutrition | |
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The Potassium Cycle | |
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The Potassium Problem in Soil Fertility | |
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Forms and Availability of Potassium in Soils | |
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Factors Affecting Potassium Fixation in Soils | |
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Practical Aspects of Potassium Management | |
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Conclusion | |
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Study Questions | |
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References | |
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Micronutrients and Other Trace Elements | |
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Deficiency Versus Toxicity | |
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Role of the Micronutrients | |
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Source of Micronutrients | |
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General Conditions Conducive to Trace Element Deficiency/Toxicity | |
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Factors Influencing the Availability of the Trace Element Cations | |
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Organic Compounds as Chelates | |
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Factors Influencing the Availability of the Trace Element Anions | |
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Need for Nutrient Balance | |
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Trace Element Cleanup and Metal Hyperaccumulators | |
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Soil Management and Micronutrient Needs | |
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Conclusion | |
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Study Questions | |
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References | |
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Practical Nutrient Management | |
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Goals of Nutrient Management | |
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Environmental Quality | |
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Nutrient Resources and Cycles | |
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Recycling Nutrients through Animal Manures | |
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Industrial and Municipal By-Products | |
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Practical Utilization of Organic Nutrient Sources | |
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Inorganic Commercial Fertilizers | |
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Fertilizer Application Methods | |
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Timing of Fertilizer Application | |
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Diagnostic Tools and Methods | |
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Soil Analysis | |
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Site-Specific Nutrient Management | |
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Site-Index Approach to Phosphorus Management | |
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Broader Aspects of Fertilizer Practice | |
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Conclusion | |
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Study Questions | |
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References | |
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Soil Erosion and Its Control | |
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Significance of Soil Erosion and Land Degradation | |
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On-Site and Off-Site Effects of Accelerated Soil Erosion | |
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Mechanics of Water Erosion | |
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Models to Predict the Extent of Water-Induced Erosion | |
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Factors Affecting Interrill and Rill Erosion | |
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Conservation Tillage | |
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Vegetative Barriers | |
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Control of Gully Erosion and Mass Wasting | |
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Control of Accelerated Erosion on Range and Forest Land | |
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Erosion and Sediment Control on Construction Sites | |
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Wind Erosion: Importance and Factors Affecting It | |
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Predicting and Controlling Wind Erosion | |
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Land Capability Classification as a Guide to Conservation | |
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Progress in Soil Conservation | |
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Real Value of Soil Conservation | |
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Conclusion | |
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Study Questions | |
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References | |
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Soils and Chemical Pollution | |
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Toxic Organic Chemicals | |
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Kinds of Organic Contaminants | |
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Behavior of Organic Chemicals in Soil | |
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Effects of Pesticides on Soil Organisms | |
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Remediation of Soils Contaminated with Organic Chemicals | |
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Contamination with Toxic Inorganic Substances | |
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Potential Hazards of Chemicals in Sewage Sludge | |
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Reactions of Inorganic Contaminants in Soils | |
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Prevention and Elimination of Inorganic Chemical Contamination | |
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Landfills | |
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Radionuclides in Soil | |
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Radon Gas from Soils | |
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Conclusion | |
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Study Questions | |
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References | |
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Geographic Soils Information | |
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Soil Spatial Variability in the Field | |
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Techniques and Tools for Mapping Soils | |
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Modern Technology for Soil Investigations | |
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Remote Sensing Tools for Soils Investigations | |
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Air Photos | |
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Satellite Imagery | |
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Soil Surveys | |
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The County Soil Survey Report and Its Utilization | |
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Geographic Information Systems | |
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GIS, GPS, and Site-Specific Agriculture | |
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Conclusion | |
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Study Questions | |
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References | |
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Global Soil Quality as Affected by Human Activities | |
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The Concept of Soil Quality/Soil Health | |
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Soil Resistance and Resilience | |
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Sustaining Biological Productivity | |
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The Population Explosion | |
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Intensified Agroecosystems--The Green Revolution | |
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Effects of Intensified Agroecosystems on Soil Quality or Health | |
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Forced Production Intensification | |
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Prospects for the Future | |
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Modified Intensive Agroecosystems | |
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Improving Low-Yielding Agricultural Systems | |
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Improving Soil Quality in sub-Saharan Africa | |
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Improving Soil Quality in Asia and Latin America | |
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Conclusion | |
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Study Questions | |
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References | |
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Canadian and FAO Soil Classification Systems | |
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SI Units, Conversion Factors, and Periodic Table of the Elements | |
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Glossary | |
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Index | |