SOILS Most important result of weathering and Erosion is soil Soils - soil science = PEDOLOGY Residual soil - soil made from local bedrock (weathered material)
Post on 28-Dec-2015
SOILS Most important result of weathering and Erosion is soil Soils - soil science = PEDOLOGY Residual soil - soil made from local bedrock (weathered material) Transport soil - soil that was moved by wind, water, ice, or gravity (weathered and eroded material)
SOIL Factors determining soil makeup1. Climate - Rainfall amount and temperature (most important)2. Parent Rock - Type and chemical composition3. Vegetation - Roots and Leaves4. Topography - hilliness, etc.5. Time - how long to develop
MATURE VS. IMMATURE SOILMature soil is soil that is fully developed! Has a distinguished A,B, and C horizon.Forest soil, Grassland soil, and Tropical SoilImmature soil is soil that is not fully developed! Does not have a distinguished A,B and C horizon. Ex. Desert soil, Arctic soil
PEDALFERS VS. PEDOCALS Pedalfers - Found in eastern half of U.S. where rainfall exceeds 25 inches/yeara. Ped - soil / Al - aluminum / Fe - ferrum - iron al from clay , fe from iron oxide2. Pedocals -
SOILS PROFILE Soil Profile - a cross reaction of soil down to the bedrock. Almost all soils show a profile of 3 distinct layers or zones (A,B,C)A. A (horizon) topsoil, gray or black, has humusB. B (horizon) subsoil, more clay is washed downC. C (horizon) Rock fragments and slightly weathered bedrockNote: More detailed description in your packet.
SOIL TYPES AND CLIMATE Soil types and climate1.Most important factor affecting soil is the climateA. Tropical soil - Warm and wet, speed up chemical weathering. Thus soil forms more quickly. Infertile due to leaching because of rain (high temp. and heavy rainfall). Note: 3 metersB. Grassland soil - enough rain for grass but not trees. Thick A horizon and very fertile. Note: 1 meterC. Forest soil - Humid regions with cool season. Well developed horizons. Less than 1 meter. Not very fertile.D. Arctic soils - High elevation and latitude. Very few layers, shallow. Permafrost.
SOIL CONSERVATIONB. SOIL CONSERVATION1. Soil Erosion - movement of topsoil by water and wind 4 bill tons (water), 1 bill tons (wind) = loss of topsoilREDUCE IT!!!!1. Windbreaks (level plains)2. Contour farming (plant parallel to land contours3. Terraces (flattened slopes)4. Strip cropping5. No till
RATES OF SOIL FORMATION Factors of Rates of Soil Formaiton1. The rocks themselves - Igneous and metamorphic most resistant, sedimentary least resistant because of pores.2. Surface Area3. Climate - Warm and wet = chemical weathering Cold and Dry = mechanical weathering4. Topography5. Biological Factors