Chapter 2 Soil Origin and Development T 2

















- Slides: 17
Chapter 2 Soil Origin and Development T 2 - Soil Science & Management, 4 E
Objectives • • T 2 - Define a soil body List examples of five soil-forming factors Describe how soils develop Describe the horizons of a soil profile Soil Science & Management, 4 E
Terms to Know • • • T 2 - Alluvial fan Alluvial soil Chemical weathering Colluvium Delta Eluviation Eolian deposit Floodplains Frost wedging Glacial drift Glacial outwash • • • Glacial till Hydrolysis Igneous rock Illuviation Lacustrine Leaching Levee Loess Marine sediment Master horizon Metamorphic rock (continued) Soil Science & Management, 4 E
Terms to Know T 2 - • • • Mineral soil Organic soil Oxidation-reduction Parent material Pedology Pedon Physical weathering Plow layer Polypedon Residual soil River terrace Root wedging • • • Sedimentary rock Soil genesis Soil horizon Soil profile Solum Solution Subsoil Talus Topsoil Transported soil Weathering Soil Science & Management, 4 E
The Soil Body Figure 2 -1 T 2 - Soil Science & Management, 4 E
Rocks and Minerals • Igneous rock • Sedimentary rock • Metamorphic rock T 2 - Soil Science & Management, 4 E
Rocks and Minerals Figure 2 -4 T 2 - Soil Science & Management, 4 E
Igneous Rock Figure 2 -5 T 2 - Soil Science & Management, 4 E
Metamorphic Rock Figure 2 -6 T 2 - Soil Science & Management, 4 E
Parent Material Figure 2 -8 T 2 - Soil Science & Management, 4 E
Parent Material • • • Glacial ice Wind Water Gravity Volcanic deposits Organic deposits Figure 2 -9 Figure 2 -11 T 2 - Soil Science & Management, 4 E
Climate Figure 2 -13 T 2 - Soil Science & Management, 4 E
Organisms Figure 2 -14 T 2 - Soil Science & Management, 4 E
Topography • Influences soil development mainly by affecting water movement T 2 - Soil Science & Management, 4 E
Time • Soils change over time due to aging process • Humans T 2 - Soil Science & Management, 4 E
The Soil Profile • Master horizons • Subdivisions of master horizons Figure 2 -19 T 2 - Soil Science & Management, 4 E
Summary • Soils form from minerals broken up by action of weathering, plant roots, and the addition of decaying plant parts • Five factors govern soil development: - Parent material - Climate - Life - Topography - Time T 2 - Soil Science & Management, 4 E