Soil Composition and Importance p. 1 Preview and Important Facts p. 1 What Is Soil? p. 1 Components of Soil p. 3 Historical Perspectives p.

Transcription

1 Preface p. xvii Soil Composition and Importance p. 1 Preview and Important Facts p. 1 What Is Soil? p. 1 Components of Soil p. 3 Historical Perspectives p. 8 Soil-A Precious Resource p. 13 Soil Quality p. 21 Summary p. 24 Questions p. 25 For Further Study p. 25 Soil Physical Properties p. 26 Preview and Important Facts p. 26 Soil Texture p. 27 Rock Fragments p. 32 Soil Structure p. 32 Bulk Density p. 35 Soil Porosity and Permeability p. 37 Soil Air p. 40 Consistence (Strength) p. 43 Soil Color p. 43 Soil Temperature p. 48 Soil Physical Properties and Engineering p. 54 Summary p. 60 Questions p. 61 For Further Study p. 62 Soil Water Properties p. 63 Preview and Important Facts p. 63 Water Chemistry p. 64 Soil Water Content p. 65 Soil Water Potential and Availability p. 66 Soils as Water Reservoirs p. 75 Methods of Determining Water Content or Potential p. 75 Water Flow Into and Through Soils p. 81 Water Uptake by Plants p. 85 Consumptive Use and Water Efficiency p. 88 Reducing Water Loss p. 91 Summary p. 94 Questions p. 95 For Further Study p. 96 Soil Chemical Properties p. 97

2 Preview and Important Facts p. 97 Soil Clays p. 98 Organic Colloids (Humus) p. 110 Cation Exchange p. 110 Anion Exchange and Adsorption p. 116 Soil ph p. 117 Equilibrium and Buffering p. 121 Summary p. 122 Questions p. 123 For Further Study p. 123 Organisms and Organic Residues p. 124 Preview and Important Facts p. 124 Animalia: Rodents, Worms, and Insects p. 125 Plantae: Plants p. 129 Fungi: Molds, Mushrooms, and Mycorrhizae p. 130 Protista p. 133 Monera: Bacteria p. 134 Soil Viruses and Viroids p. 140 Conditions for Microbial Activity p. 141 Composition of Organic Matter p. 144 Decomposition of Organic Matter p. 145 Effects of Soil Organic Matter p. 149 Organic Waste Materials p. 153 Summary p. 157 Questions p. 158 For Further Study p. 158 Soil Formation and Morphology p. 159 Preview and Important Facts p. 159 Weathering of Soil Minerals p. 160 Soil Formation: Building a Matrix for Living Organisms p. 162 Soil-Forming Factors p. 163 Landforms and Soil Development p. 171 Morphology of Soil Horizons p. 181 Diagnostic Horizons p. 185 Degradation of Soils p. 188 Soil Individuals and Mapping Units p. 191 Summary p. 192 Questions p. 193 For Further Study p. 194 Soil Taxonomy p. 195 Preview and Important Facts p. 195

3 U.S. System of Soil Taxonomy p. 196 Constructing Taxonomic Names p. 200 Soil Moisture and Temperature Regimes p. 200 Additional Terminology for Family Groupings p. 205 Distribution of Soil Orders p. 207 Soil Order: Gelisols (Soils with Permafrost) p. 208 Soil Order: Histosols (Organic Soils) p. 209 Soil Order: Entisols (Soils with Little or No Horizon Development) p. 210 Soil Order: Inceptisols (Soils with Weak Horizon Development) p. 212 Soil Order: Andisols (Young Volcanic Soils) p. 213 Soil Order: Aridisols (Desert Soils) p. 214 Soil Order: Mollisols (Prairie Soils) p. 216 Soil Order: Vertisols (Shrink-Swell Clays) p. 217 Soil Order: Alfisols (Fertile Soils with Subsoil Clay) p. 219 Soil Order: Spodosols (Soils with Humus under Sand) p. 221 Soil Order: Ultisols (Highly Leached Soils with Subsoil Clay) p. 222 Soil Order: Oxisols (Highly Oxidized Soils) p. 224 Other Soil Classification Systems p. 225 Summary p. 227 Questions p. 227 For Further Study p. 228 Acidic Soils and Salt-Affected Soils p. 229 Preview and Important Facts p. 229 Why Some Soils Are Acidic p. 230 Ecological Relation of Soil Acidity p. 233 Composition of Lime p. 233 Reactions of Lime Added to Acidic Soils p. 236 Crops, Lime, and Soil p. 237 Acidifying Soils p. 242 Soluble Salts and Plant Growth p. 243 Saline and Sodic Soils p. 246 Salt Balance p. 252 Reclaiming Salty Soils p. 254 Managing Salty Soils p. 258 Monitoring Salts in the Field p. 261 Summary p. 262 Questions p. 263 For Further Study p. 263 Plant Nutrients p. 264 Preview and Important Facts p. 264 Essential Elements p. 265

4 Mechanisms of Nutrient Uptake p. 265 Soil Nitrogen Gains and Transformations p. 267 Nitrogen Losses from the System p. 273 Nitrogen Balance p. 275 Materials Supplying Nitrogen p. 276 Soil Phosphorus p. 280 The Phosphorus Problem p. 280 Managing Soil Phosphorus p. 285 Materials Supplying Phosphorus p. 287 Soil Potassium p. 288 Soil Calcium p. 292 Soil Magnesium p. 293 Soil Sulfur p. 294 Soil Boron p. 296 Soil Chloride p. 299 Soil Copper p. 299 Soil Iron p. 300 Soil Manganese p. 303 Soil Molybdenum p. 304 Soil Zinc p. 305 Nickel and the Beneficial Elements p. 308 Summary p. 308 Questions p. 309 For Further Study p. 310 Soil Fertility Management p. 311 Preview and Important Facts p. 311 Goals and Concerns in Fertility Management p. 312 Scale of Land Management p. 313 Soil Sampling p. 316 Soil Tests p. 319 Analysis of Plants p. 325 Fertilizer Recommendations p. 329 Fertilizer Quality p. 332 Fertilizer Calculations p. 334 Techniques of Fertilizer Application p. 336 Fertilizer Efficiency p. 344 Livestock Manure as Fertilizer p. 348 Summary p. 354 Questions p. 355 For Further Study p. 355 Soil Erosion p. 356

5 Preview and Important Facts p. 356 The Soil Erosion Problem p. 358 Nature of Water Erosion p. 361 Factors Affecting Erosion by Water p. 364 Erosion Tolerance p. 368 Water Erosion Control p. 369 Nature of Wind Erosion p. 375 Factors Affecting Erosion by Wind p. 376 Wind-Erosion Control p. 378 Summary p. 381 Questions p. 382 For Further Study p. 382 Tillage and Farming Systems p. 383 Preview and Important Facts p. 383 Purposes for Tillage p. 385 Tillage Terminology p. 389 Reducing or Eliminating Tillage p. 391 Farming Systems and Environmental Quality p. 396 Transgenic Crops p. 397 Sustainable Agriculture and Organic Farming p. 401 Summary p. 405 Questions p. 406 For Further Study p. 406 Water Resources and Irrigation p. 407 Preview and Important Facts p. 407 Water Resources for Irrigation p. 408 Irrigation Water Quality p. 414 Meeting Water Needs of Plants p. 417 Methods of Applying Water p. 421 Special Irrigation Techniques p. 430 Irrigating Efficiently p. 433 Increasing Water Supplies p. 434 Summary p. 435 Questions p. 436 For Further Study p. 436 Wetlands and Land Drainage p. 437 Preview and Important Facts p. 437 Wetlands Trends and Laws p. 438 Wetlands Characteristics p. 440 Functions of Wetlands p. 443 Drainage to Improve Soil Conditions p. 445

6 Drainage Pros and Cons p. 447 Drainage System Selection p. 448 Surface Drainage Systems p. 449 Subsurface Drainage Systems p. 452 Summary p. 455 Questions p. 455 For Further Study p. 456 Pollution of Soil, Water, and Air p. 457 Preview and Important Facts p. 457 Threats to the Environment p. 458 Pollution Terminology p. 460 Plant Nutrients p. 461 Organic Wastes p. 464 Pesticides p. 469 Heavy Metals p. 472 Natural Toxins p. 474 Particulates and Gases p. 475 Radionuclides p. 481 Soluble Salts p. 482 Soil Sediments as Pollutants p. 483 Summary p. 484 Questions p. 485 For Further Study p. 485 Toward Environmental Integrity p. 487 Preview and Important Facts p. 487 Environmental Laws p. 489 Best Management Practices p. 490 Managing Organic Wastes p. 492 Reducing Pesticide Contamination p. 494 Improving Water Quality p. 500 Improving Air Quality p. 503 Improving Soil Quality p. 507 Remediation of Contaminated Soil p. 511 Summary p. 514 Questions p. 515 For Further Study p. 515 Soil Surveys and Land-Use Planning p. 517 Preview and Important Facts p. 517 Conducting a Soil Survey p. 518 Soil Survey Reports p. 518 Electronic Databases for Soils p. 523

7 Special Soil Designations p. 523 Land Evaluation p. 524 Data Interpretations for Soil Uses p. 529 Controlling Land Use p. 534 Summary p. 539 Questions p. 540 For Further Study p. 540 Greenhouse Soils and Soilless Culture p. 541 Preview and Important Facts p. 541 Root Media p. 542 Root Media Mixes p. 545 Pasteurization of Media p. 547 Watering p. 548 Fertilizing p. 549 Soil and Tissue Testing p. 550 Hydroponics: Solution Culture p. 551 Summary p. 555 Questions p. 557 For Further Study p. 557 p. 559 p. 564 Glossary p. 567 Index p. 591 Table of Contents provided by Blackwell's Book Services and R.R. Bowker. Used with permission.