Soil Science Landscape Design Mrs Clinkscales 4 Components

Soil Science Landscape Design Mrs. Clinkscales

4 Components of Soil • 50% Solids – Mineral Matter (45%) – Organic Matter (5%) • 50% Pore Space – Air (25%) – Water (25%)

Soil Formation Animation • http: //courses. soil. ncsu. edu/resources/soil_cl assification_genesis/soil_formation/soil_trans form. swf

Soil Particles • From Largest to Smallest – Sand – Silt – Clay

Soil Particle - Sand • . 05 – 2 mm • Round Shape • Feels Gritty Attributes to Soil – Adds porosity – Reduces water holding capacity

Soil Particle - Silt • . 002 -. 05 mm • Round Shape – but very small to detect • Feels smooth but not sticky Attributes to Soil: – Moderately good for porosity – Helps water holding capacity

Soil Particle - Clay • Less than. 002 mm • Flat or Platy shape • Sticky when wet – ribbon test Attributes to Soil: – Bad for porosity – Ties up water so plants can’t use it

Relative Size of Particles

How are soils formed? • Weathering –Chemical/Biological • Chemical reactions (acids, bases, ions, etc) –Mechanical/Physical • Direct contact with atmospheric conditions (heat, water, ice, pressure)

How long does soil formation take? For 1” of topsoil to form it takes about 1000 years

What are the functions of soil? 1. Anchor plants to the ground 2. Provide plants with water, air, and nutrients 3. Provide an environment for microorganisms to live

Profiles and Horizons • Soil Profile – a “side view” of the various layers of soil; a vertical cut of soil to view the soil layers. • Soil Horizon – a layer of soil approximately parallel to the surface, having distinct characteristics produced by soil formation processes, used to classify and make interpretations