Soil

Soil

1. Influences on formation

   • living things
   • Climate
   • parent material
   • landscape
   • vegetation
   • time

2. Compostion

   • 43% mineral matter
   • 25% air
   • 25% water
   • 5% humus
   • 2% living things

3. Profile

   • O Horizon
     • plant litter
   • A Horizon
     • Topsoil
   • B Horizon
     • Subsoil
   • C Horizon
     • Bed rock/ parent material

4. Leaching

   • Hardpan
     • Layer of imperable rock at the bottom of the A Horizon

5. Characteristics affecting vegetation

   • Depth
   • Fertility
   • Acidity
   • Drainage

6. Human Interference

   • Soil Erosion
     • Overgrazing
     • Overcropping
     • Deforestation

7. Irish Soils

   • Brown Earth
     • fertile
   • Podzols
     • Not very fertile
   • Gley soils
   • peaty soils

8. World soils

   • Tropical Red Soils