Soils

Soils

1. Organic matter

2. Minerals

   • Regiloth
     • residual minerals
     • Secoundary minerals
     • rock Fragments
     • Partially weathered/unweathered minerals

3. Soil water

4. Soil Air

5. Soil Horizon

   • O1: undecomposed organic matter
   • A1: mineral surface layer with humified organic matter. daker than underlying horizon
   • O2: partially decomposed organic matter
   • A2: subsurface mineral layer which is lighter in colour and sometimes bleached
   • B horizon - high concentrations clay, iron, aliminium and/or organic content. maximum devlopment and structure. stronger or consistent colours with A horizon
   • R horizon: Bed rock/ parent material
   • C horizon: weathered materials usually showing remenant structure parent material

6. Particulate size distribution

   • history and processes of soil formation
   • Sand - 20 - 2000 microns Silt - 2-20 microns Clay - <2 microns

7. D horizon - soil material underlying and separated from mordern soils. under A/B horizon. buried soils the original horizons can be identified