Soil Management for Optimized Productivity Under Rainfed Conditions in the Semi-Arid Tropics. - I. Introduction. - II. Soils of the Semi-Arid Tropics. - III. Major Characteristics of SAT Vertisols and Alfisols. - IV. Dryland Management Options for SAT Vertisols and Alfisols. - V. Conclusions. - References. - Soil Profile Modification for Increasing Crop Production. - I. Introduction. - II. Literature Review and Discussion. - III. Summary. - References. - The Effect of Exchangeable Sodium and Electrolyte Concentration on Crust Formation. - I. Introduction. - II. Crust Properties as Determined by the Infiltration Rate (IR). - III. Effect of ESP and Electrolyte Concentration on the Structure of the Soil Crust. - IV. Effect of Soil Sodicity on Crust Formation (and Rain Infiltration)Field Studies. - V. Summary. - References. - Ammonia Volatilization from Ammonium or Ammonium-Forming Nitrogen Fertilizers. - I. Introduction. - II. Methods for Estimating NH3 Volatilization. - III. Chemistry of NH3 Volatilization. - IV. Magnitude of NH3 Losses. - V. Chemical and Physical Parameters That Control Absolute NH3 Losses. - VI. Ammonia Loss from Flooded Systems. - VII. Volatilization Loss of Nitrogen Following Forest Fertilization. - VIII. Ammonia Transfer Cycle. - IX. Conclusion. - References. - The Effect of Pedogenic Environments on Iron Oxide Minerals. - I. Introduction. - II. Pedoenvironments and Fe(III) Oxide Minerals. - III. Aluminum Substitution. - IV. Pedoenvironments and Crystal Quality. - V. Iron Oxide Minerals and Soil Classification. - References. - Soil Testing. - I. Introduction. - II. Research Required as a Basis for Soil Testing. - III. Taking the Sample. - IV. Laboratory Procedures. - V. Soil Test Calibration and Interpretation. - VI. Rating Soil-Test Values and Use of a Fertility Inde. - VII. Making Limeand Fertilizer Recommendations from Soil Tests. - References. - Boron in Water Soils and Plants. - I. Introduction. - II. Boron Chemistry in Aqueous Media. - III. Boron-Soil Interaction. - IV. Boron in Soil-Plant Relations. - V. Soil Reclamation and Management. - References. - Relationship between Soil Physical Properties and Crop Production. - I. Introduction. - II. Factors Directly Affecting Plant Growth. - III. Factors Indirectly Affecting Plant Growth. - IV. Interrelationships of Soil Physical Factors. - V. Relationships between Soil Physical Conditions and Management. - VI. Soil Erosion and Productivity. - VII. Conclusions. - References. Language: English