Soil science Prof. Blaskó, Lajos Created by XMLmind XSL-FO Converter. Soil science: Prof. Blaskó, Lajos Publication date 2011 Szerzői jog © 2011 Debreceni Egyetem. Agrár- és Gazdálkodástudományok Centruma Created by XMLmind XSL-FO Converter. Tartalom ............................................................................................................................................................ v 1. Definition of soil ............................................................................................................................. 1 1. .............................................................................................................................................. 1 2. Soil functions .................................................................................................................................. 2 1. .............................................................................................................................................. 2 3. The composition of the soil ............................................................................................................ 4 1. .............................................................................................................................................. 4 2. Mineral matter ....................................................................................................................... 5 3. Soil organic matter ................................................................................................................ 7 4. Soil pores .............................................................................................................................. 9 4. Soil horizons ................................................................................................................................. 11 1. ............................................................................................................................................ 11 5. Soil chemical properties ............................................................................................................... 15 1. ............................................................................................................................................ 15 2. Soil pH ................................................................................................................................ 15 3. Cation and anion exchange capacity (CEC) ........................................................................ 16 4. Sources of negative charge: ................................................................................................ 16 5. Measurement of CEC. ......................................................................................................... 21 6. Base saturation .................................................................................................................... 22 7. CEC and availability of nutrients ........................................................................................ 23 8. Anion-exchange capacity (AEC) ........................................................................................ 24 9. Soil salinity ......................................................................................................................... 26 6. Physical properties ........................................................................................................................ 27 1. ............................................................................................................................................ 27 2. Texture ................................................................................................................................ 27 3. Effects of texture on soil properties .................................................................................... 28 4. Aggregation and soil structure ............................................................................................ 29 5. Effects of structure on soil properties .................................................................................. 31 6. Porosity ............................................................................................................................... 31 7. Soil-water relationships ................................................................................................................ 34 1. Soil water holding capacity ................................................................................................. 35 2. Forms of soil water storage ................................................................................................. 35 3. Field capacity and permanent wilting percentage ............................................................... 38 4. Tillage and moisture content ............................................................................................... 38 5. Soil moisture retention curve .............................................................................................. 38 6. Soil drainage ....................................................................................................................... 40 7. Soil drainage and soil color ................................................................................................. 41 8. Drainage classes .................................................................................................................. 41 9. Soil aeration ........................................................................................................................ 52 10. Soil thermal properties ...................................................................................................... 53 11. Soil temperature ................................................................................................................ 53 12. Effects of water on thermal properties .............................................................................. 54 8. Nutrient cycles .............................................................................................................................. 55 1. ............................................................................................................................................ 55 2. Nitrogen fixation ................................................................................................................. 55 3. Nitrogen uptake ................................................................................................................... 56 4. Nitrogen mineralization ...................................................................................................... 56 5. Nitrification ......................................................................................................................... 56 6. Denitrification ..................................................................................................................... 56 9. Nitrogen loss ................................................................................................................................. 58 1. Leaching of Nitrate-N ......................................................................................................... 58 2. Denitrification of Nitrate-N ................................................................................................ 58 3. Nitrogen immobilization .................................................................................................... 58 4. Phosphorus cycle ................................................................................................................. 59 5. Potassium cycle ................................................................................................................... 59 6. Eutrophication .................................................................................................................... 60 iii Created by XMLmind XSL-FO Converter. Soil science 7. Soil Classification Systems ................................................................................................. 61 10. United States Soil Classification System .................................................................................... 62 1. ............................................................................................................................................ 62 11. World Reference Base for Soil Resources .................................................................................. 66 1. ............................................................................................................................................ 66 12. The major soil types of Europe ................................................................................................... 69 1. ............................................................................................................................................ 69 13. Land degradation ...................................................................................................................... 107 1. .......................................................................................................................................... 107 2. Erosion .............................................................................................................................. 109 3. Causes of Human Erosion ................................................................................................