| Contents Notes |
1. THE SOIL IN PERSPECTIVE -- 1:1 What is soil? -- 1:2 Evaluation of modern concepts of soil -- 1:3 The approach -- edaphological versus pedological -- 1:4 A field view of soil -- 1:5 The soil profile -- 1:6 Subsoil and surface soil -- 1:7 Mineral (inorganic) and organic soils -- 1:8 General definition of mineral soils -- 1:9 Four major components of soils -- 1:10 Mineral (inorganic) constituents in soils -- 1:11 Soil organic matter -- 1:12 Soil water -- a dynamic solution -- 1:13 Soil air -- also a changeable constituent -- 1:14 The soil -- a tremendous biological laboratory -- 1:15 Clay and humus -- the seat of soil activity -- 2. SUPPLY AND AVAILABILITY OF PLANT NUTRIENTS IN MINERAL SOILS -- 2:1 Factors controlling the growth of higher plants -- 2:2 The essential elements -- 2:3 Essential elements from air and water -- 2:4 Essential elements from the soil -- 2:5 Macronutrient contents of mineral soils -- 2:6 Forms of macronutrients in soils -- 2:7 Transfer of plant nutrients to available forms -- 2:8 Soil solution -- 2:9 Nutritional importance of soil pH -- 2:10 Forms of elements used by plants -- 2:11 Soil and plant interrelations -- 2:12 Soil fertility inferences -- 3. SOME IMPORTANT PHYSICAL PROPERTIES OF MINERAL SOILS -- 3:1 Classification of soil particles and mechanical analysis -- 3:2 Physical nature of the soil separates -- 3:3 Mineralogical and chemical compositions of the soil separates -- 3:4 Soil textural classes -- 3:5 Determination of soil class -- 3:6 Particle density of mineral soils -- 3:7 Bulk density of mineral soils -- 3:8 Pore space of mineral soils -- 3:9 Structure of mineral soils -- 3:10 Aggregation and its promotion in arable soils -- 3:11 Structural management of soils -- 3:12 Soil consistence -- 3:13 Tilth and tillage -- 4. SOIL COLLOIDS: THEIR NATURE AND PRACTICAL SIGNIFICANCE -- 4:1 General constitution of silicate clays -- 4:2 Adsorbed cations -- 4:3 Fundamentals of silicate clay structure -- 4:4 Mineralogical organization of silicate clays -- 4:5 Source of the negative charge on silicate clays -- 4:6 Chemical composition of silicate clays -- 4:7 Genesis of silicate clays -- 4:8 Mineral colloids other than silicates -- 4:9 Geographic distribution of clays -- 4:10 Organic soil colloids -- humus -- 4:11 Colloids -- acid salts -- 4:12 Cation exchange -- 4:13 Cation exchange capacity -- 4:14 Cation exchange capacity of whole soils -- 4:15 Percentage base saturation of soils -- 4:16 Cation exchange and the availability of nutrients -- 4:17 Other properties of colloids -- plasticity, cohesion, swelling, shrinkage, dispersion, and flocculation -- 4:18 Conclusion -- 5. ORGANISMS OF THE SOILS -- 5:1 Organisms in action -- 5:2 Organism numbers, biomass, and metabolic activity -- 5:3 Earthworms -- 5:4 Soil microanimals -- 5:5 Roots of higher plants -- 5:6 Soil algae -- 5:7 Soil fungi -- 5:8 Soil actinomycetes -- 5:9 Soil bacteria -- 5:10 Conditions affecting the growth of soil bacteria -- 5:11 Injurious effects of soil organisms on higher plants -- 5:12 Competition among soil microorganisms -- 5:13 Effects of agricultural practice on soil organisms -- 5:14 Activities of soil organisms beneficial to higher plants -- 6. ORGANIC MATTER OF MINERAL SOILS -- 6:1 Sources of soil organic matter -- 6:2 Composition of plant residues -- 6:3 Decomposition of organic compounds -- 6:4 Energy of soil organic matter -- 6:5 Simple decomposition products -- 6:6 The carbon cycle -- 6:7 Simple products carrying nitrogen -- 6:8 Simple products carrying sulfur -- 6:9 Mineralization of organic phosphorus -- 6:10 Humus -- genesis and definition -- 6:11 Humus -- nature and characteristics -- 6:12 Direct influence of organic compounds on higher plants -- 6:13 Influence of soil organic matter on soil properties -- 6:14 Carbon-nitrogen ratio -- 6:15 Significance of the carbon-nitrogen ratio -- 6:16 Amount of organic matter and nitrogen in soils -- 6:17 Factors affecting soil organic matter and nitrogen -- 6:18 Regulation of soil organic matter -- 7. SOIL WATER: CHARACTERISTICS AND BEHAVIOR -- 7:1 Structure and related properties of water -- 7:2 Soil water energy concepts -- 7:3 Soil moisture content versus suction -- 7:4 Measuring soil moisture -- 7:5 Capillary fundamentals as they relate to soil water -- 7:6 Types of soil water movement -- 7:7 Saturated flow through soils -- 7:8 Unsaturated flow in soils -- 7:9 Water movements in stratified soils -- 7:10 Water vapor movement -- 7:11 Retention of soil moisture in the field -- 7:12 Conventional soil moisture classification schemes -- 7:13 Factors affecting amount and use of available soil moisture -- 7:14 How plants are supplied with water -- capillarity and root extension -- 7:15 Conclusion -- 8. VAPOR LOSSES OF SOIL MOISTURE AND THEIR REGULATION -- 8:1 Interception of rain water by plants -- 8:2 The soil-water-plant continuum -- 8:3 Evapo-transpiration -- 8:4 Magnitude of evaporation losses -- 8:5 Efficiency of water use -- 8:6 Evaporation control: mulches and cultivation -- 8:7 Vaporization control in humid regions -- 8:8 Vaporization control in semiarid and subhumid regions -- 8:9 Evaporation control of irrigated lands -- 9. LIQUID LOSSES OF SOIL WATER AND THEIR CONTROL -- 9:1 Percolation and leaching -- methods of study -- 9:2 Percolation losses of water -- 9:3 Leaching losses of nutrients -- 9:4 Land drainage -- 9:5 Open ditch drainage -- 9:6 Tile drains -- 9:7 Benefits of land drainage -- 9:8 Runoff and soil erosion -- 9:9 Accelerated erosion -- mechanics -- 9:10 Accelerated erosion -- causes and rate factors -- 9:11 Types of water erosion -- 9:12 Sheet and rill erosion -- losses under regular cropping -- 9:13 Sheet and rill erosion -- methods of control -- 9:14 Gully erosion and its control -- 9:15 Wind erosion -- its importance and control -- 9:16 Conservation treatment needs in the United States -- 9:17 Summary of soil moisture regulation 10. SOIL AIR AND SOIL TEMPERATURE -- 10:1 Soil aeration defined -- 10:2 Soil aeration problems in the field -- 10:3 Composition of soil air -- 10:4 Factors affecting the composition of soil air -- 10:5 Effects of soil aeration on biological activities -- 10:6 Other effects of soil aeration -- 10:7 Aeration in relation to soil and crop management -- 10:8 Soil temperature -- 10:9 Absorption and loss of solar energy -- 10:10 Specific heat of soils -- 10:11 Heat of vaporization -- 10:12 Movement of heat in soils -- 10:13 Soil temperature data -- 10:14 Soil temperature control -- 11. ORIGIN, NATURE, AND CLASSIFICATION OF PARENT MATERIALS -- 11:1 Classification and properties of rocks -- 11:2 Weathering -- a general case -- 11:3 Mechanical forces of weathering -- 11:4 Chemical processes of weathering -- 11:5 Factors affecting weathering of minerals -- 11:6 Weathering in action -- genesis of parent materials -- 11:7 Geological classification of parent materials -- 11:8 Residual parent material -- 11:9 Colluvial debris -- 11:10 Alluvial stream deposits -- 11:11 Marine sediments -- 11:12 The Pleistocene ice age -- 11:13 Glacial till and associated deposits -- 11:14 Glacial outwash and lacustrine sediments -- 11:15 Glacial-aeolian deposits -- 11:16 Agricultural significance of glaciation -- 12. SOIL FORMATION, CLASSIFICATION, AND SURVEY -- 12:1 Factors influencing soil formation -- 12:2 Weathering and soil profile development -- 12:3 The soil profile -- 12:4 Concept of individual soils -- 12:5 Soil classification in the United States -- 12:6 Soil classification -- new comprehensive system -- 12:7 Soil orders -- 12:8 Soil suborders, great groups, and subgroups -- 12:9 Soil families, series, phases, associations, and catenas -- 12:10 Soil classification -- 1949 system -- 12:11 Soil survey and its utilization -- 12:12 Land capability classification -- 13. ORGANIC SOILS (HISTOSOLS): THEIR NATURE, PROPERTIES, AND UTILIZATION -- 13:1 Genesis of organic deposits -- 13:2 Area and distribution of peat accumulations -- 13:3 Peat parent materials -- 13:4 Uses of peat -- 13:5 Classification of organic soils -- 13:6 Physical characteristics of field peat soils -- 13:7 Colloidal nature of organic soils -- 13:8 Chemical composition of organic soils -- 13:9 Bog lime -- its importance -- 13:10 Factors that determine the value of peat and muck soils -- 13:11 Preparation of peat for cropping -- 13:12 Management of peat soils -- 13:13 Organic versus mineral soils -- 14. SOIL REACTION: ACIDITY AND ALKALINITY -- 14:1 Source of hydrogen ions -- 14:2 Colloidal control of soil reaction -- 14:3 Major changes in soil pH -- 14:4 Minor fluctuations in soil pH -- 14:5 Hydrogen ion heterogeneity of the soil solution -- 14:6 Active versus exchange acidity -- 14:7 Buffering of soils -- 14:8 Buffer capacity of soils and related phases -- 14:9 Importance of buffering -- 14:10 Soil-reaction correlations -- 14:11 Relation of higher plants to soil reaction -- 14:12 Determination of soil pH -- 14:13 Soil acidity problems -- 14:14 Methods of intensifying soil acidity -- 14:15 Reaction of soils of arid regions -- 14:16 Reaction of saline and sodic soils -- 14:17 Growth of plants on halomorphic soils -- 14:18 Tolerance of higher plants to halomorphic soils -- 14:19 Management of saline and sodic soils -- 14:20 Conclusion -- 15. LIME AND ITS SOIL-PLANT RELATIONSHIPS -- 15:1 Liming materials -- 15:2 Chemical guarantee of liming materials -- 15:3 Fineness guarantee of limestone -- 15:4 Changes of lime added to the soil -- 15:5 Loss of lime from arable soils -- 15:6 Effects of lime on the soil -- 15:7 Crop response to liming -- 15:8 Overliming -- 15:9 Shall lime be applied? -- 15:10 Form of lime to apply -- 15:11 Amounts of lime to apply -- 15:12 Methods of applying lime -- 15:13 Lime and soil fertility management -- 16. NITROGEN AND SULFUR ECONOMY OF SOILS -- 16:1 Influence of nitrogen on plant development -- 16:2 Forms of soil nitrogen -- 16:3 The nitrogen cycle -- 16:4 Ammonia fixation -- 16:5 Nitrification -- 16:6 Soil conditions affecting nitrification -- 16:7 Fate of nitrate nitrogen -- 16:8 Gaseous losses of soil nitrogen -- 16:9 Fixation of atmospheric nitrogen by legume bacteria -- 16:10 Amount of nitrogen fixed by legume bacteria -- 16:11 Fate of nitrogen fixed by legume bacteria -- 16:12 Do legumes always increase soil nitrogen? -- 16:13 Fixation by organisms in symbiosis with nonlegumes -- 16:14 Nonsymbiotic fixation of atmospheric nitrogen -- 16:15 Amount of nitrogen fixed by nonsymbiosis -- 16:16 Addition of nitrogen to soil in precipitation -- 16:17 Reactions of nitrogen fertilizers -- 16:18 Practical management of soil nitrogen -- 16:19 Importance of sulfur -- 16:20 Natural sources of sulfur -- 16:21 The sulfur cycle -- 16:22 Behavior of sulfur compounds in soils -- 16:23 Sulfur and soil fertility maintenance -- 17. SUPPLY AND AVAILABILITY OF PHOSPHORUS AND POTASSIUM -- 17:1 Importance of phosphorus -- 17:2 Influence of phosphorus on plants -- 17:3 The phosphorus problem -- 17:4 Phosphorus compounds in soils -- 17:5 Factors that control the availability of inorganic soil phosphorus -- 17:6 pH and phosphate ions -- 17:7 Inorganic phosphorus availability in acid soils -- 17:8 Inorganic phosphorus availability at high pH values -- 17:9 pH for maximum inorganic phosphorus availability -- 17:10 Availability and surface area of phosphates -- 17:11 Phosphorus-fixing power of soils -- 17:12 Influence of soil organisms and organic matter on the availability of inorganic phosphorus -- 17:13 Availability of organic phosphorus -- 17:14 Practical control of phosphorus availability -- 17:15 Potassium -- the third "fertilizer" element -- 17:16 Effects of potassium on plant growth -- 17:17 The potassium problem -- 17:18 Forms and availability of potassium in soils -- 17:19 Factors affecting potassium fixation in soils -- 17:20 Practical implications in respect to potassium -- 18. MICRONUTRIENT ELEMENTS -- 18:1 Deficiency versus toxicity -- 18:2 Role of the micronutrients -- 18:3 Source of micronutrients -- 18:4 General conditions conducive to micronutrient deficiency -- 18:5 Factors influencing the availability of the micronutrient cations -- 18:6 Chelates -- 18:7 Factors influencing the availability of the micronutrient anions -- 18:8 Need for nutrient balance -- 18:9 Soil management and micronutrient needs -- 19. FERTILIZERS AND FERTILIZER MANAGEMENT -- 19:1 The fertilizer elements -- 19:2 Three groups of fertilizer materials -- 19:3 Nitrogen carriers -- two groups -- 19:4 Inorganic nitrogen carriers -- 19:5 Phosphatic fertilizer materials -- 19:6 Fertilizer materials carrying potassium -- 19:7 Sulfur in fertilizers -- 19:8 Micronutrients -- 19:9 Mixed fertilizers -- 19:10 Effect of mixed fertilizers on soil pH -- 19:11 The fertilizer guarantee -- 19:12 Fertilizer inspection and control -- 19:13 Fertilizer economy -- 19:14 Movement of fertilizer salts in the soil -- 19:15 Methods of applying solid fertilizers -- 19:16 Application of liquid fertilizers -- 19:17 Factors influencing the kind and amount of fertilizers to apply -- 19:18 Kind of crop to be fertilized -- 19:19 Chemical condition of the soil -- total versus partial analyses -- 19:20 Tests for available soil nutrients -- quick tests -- 19:21 Broader aspects of fertilizer practice -- 20. ANIMAL MANURES AND GREEN MANURES -- 20:1 Quality of manure produced -- 20:2 Chemical composition -- 20:3 Storage, treatment, and management of animal manures -- 20:4 Utilization of animal manures -- 20:5 Long-term effects of manures -- 20:6 Green manures -- defined -- 20:7 Benefits of green manures -- 20:8 Plants suitable as green manures -- 20:9 Problems with green manures -- 20:10 Practical utilization of green manures -- 21. SOILS AND CHEMICAL POLLUTION -- 21:1 Chemical pesticides -- background -- 21:2 Kinds of pesticides -- 21:3 Behavior of pesticides in soils -- 21:4 Effects of pesticides on soil organisms -- 21:5 Contamination with toxic inorganic compounds -- 21:6 Behavior of inorganic contaminants in soils -- 21:7 Prevention and elimination of inorganic chemical contamination -- 21:8 Organic wastes -- 21:9 Use of organic wastes for crop production -- 21:10 Soils as organic waste disposal sites -- 21:11 Soil salinity -- 21:12 Radionuclides in soils -- 21:13 Three conclusions -- 22. SOILS AND THE WORLD'S FOOD SUPPLY -- 22:1 Expansion of world population -- 22:2 Factors influencing world food supplies -- 22:3 The world's land resources -- 22:4 Potential of broad soil groups -- 22:5 Problems and opportunities in the tropics -- 22:6 Requisites for the future. |
