Soils Flashcards
What is soil made of? + percentages
Minerals - 45%
Air and water - 50%
Organic matter - 5%
Leaching
Removal of soluble minerals, salts and humus,which are washed downwards through the soil and may accumulate in the subsoil.
Humification
Breakdown or decomposition of plant remains leading to the formation of different types of humus.
Illuviation
Introduction of material to a soil layer.
Eluviation
Removal of materials from a soil layer.
Soil horizon
A layer of soil parallel to the soil crust whose characteristics differ from the horizons above and below.
Soil profile
A vertical cross section of a soil, divided into a number of distinct layers, referred to as horizons.
Regolith
Fragments of rock
Capillary action
Process whereby water and minerals in a solution can be drawn upwards when the rate of evapotranspiration is greater than precipitation.
Parent material
Underlying geological material (bedrock) in which soil horizons for,.
Zonal soil
Mature soils that form under the influence of climate, vegetation, and biota activity.
Intrazonal soils
Soils that do not reflect climactic or vegetation standard influence.
Azonal soil
Immature soils that lack the development of a B horizon
What are the 6 factors affecting soil formation
- Parent material
- Biotic factors
- Climate
- Man
- Relief
- Time
What is in the O horizon
Leaf litter and humus layer