Soil Flashcards
Soil
Top layer of the earths surface which consists of rocks and mineral particles mixed with decaying plants and animals.
Provides nutrients for plant growth
What is soil composed of?
Mineral particles : broken down rocks (regolith).
Air : needed for plant growth, contains oxygen and nitrogen.
Water : dissolves minerals and nutrients in the soil
Plant remains : decayed plants turn into humus
Living organisms : earthworms and bacteria break down plants to form humus
How is soil formed?
Climate : influences weathering and erosion which breaks down rock into mineral particles. Influences the growth of vegetation which living organisms turn into humus.
Time
People : fertilise and drain soil to improve it
Soil profile
Plant litter : decaying leaves and vegetation
A horizon : topsoil, brown because it contains humus
B horizon : subsoil, lighter as it has less humus and more stones
C horizon : parent rock
Soil types in Ireland
Brown soils, peaty soils, gley soils and podzol
