1. Soil Analysis Objectives To understand how soil is formed To know the different soil horizons Be able to characterize soil based on: Color Texture Structure and pH Be able to identify the type based on its constituent particle size

2.  Soil Constituents:  Air  Water  Nutrients  Organic matter  Disintegrated rock and  Microorganisms  Soil Formation Rate: 1inch/500-1000 years  Soil Erosion: Natural and Anthropogenic Cropland: 1inch/15-30 years (US,1990)

3. Desertification  Soil compaction  Overgrazing  Depletion of water resources and Drought  Salinization  Climate Change

4.  Climate ◦ High in warmer and wetter climate  Organisms ◦ Microbial decomposition ◦ Vegetation  Topographic relief ◦ Mountain/valleys: slope, wind, water, sun  Parent materials ◦ Based on geological material  Time

5. Weathering ◦ Physical ◦ Chemical ◦ Biological

8.  Texture ◦ Loam  Mixture of sand, silt and clay ◦ Soil Porosity  Sizes of spaces between soil particles  Crop production  Characteristics ◦ Color (dark, red, white) ◦ Structure (aggregated and clumped) ◦ pH ( 0-14 acidic, neutral, alkaline)  Soil and nutrients ◦ Nitrogen (N), Phosphorus (P), Potassium (K) ◦ Eutrophication ComponentsParticle Size Clay<0.002mm Silt0.002-0.05mm Sand0.05-2.0 mm

9.  Place soil in top sieve  Swirl for about 2 minutes  Discard top sieve (sieve #5)  Weigh and combine next 2 sieves ◦ (#10 + #60) = sand  Weigh 4 th sieve (#230) = silt  Weigh 5 th sieve (bottom)= clay  Calculate percentages  Use triangle method to determine texture