Topic 5 - Soil systems and society Flashcards
Soil systems storage
Include organic matter, organisms, nutrients, minerals, air and water
Transfers in the soil system
Include biological mixing and leaching (minerals dissolved in water moved through soil)
Inputs to the soil system
Leaf litter and inorganic matter from parent rock, precipitation and energy
Outputs from the soil system
Include uptake by plants and soil erosion
Transformations in the soil system
Include decomposition, weathering and nutrient cycling
Soil
A complex ecosystem made up of minerals, organic matter, gases and liquid, which forms the habitat for many animals and plants
Horizons in soil
Different layers of the soil
O Horizon - leaf litter
A Horizon - mineral horizon at the surface showing organic matter enrichment
E Horizon - Subsurface horizon showing depletion of organic matter, clay, iron and aluminium compounds
B Horizon - subsoil horizon showing enrichment of clay material, iron, aluminium or organic compounds
C Horizon - loosened or unconsolidated material
R Horizon - bedrock
Translocation
Materials in the soil are sorted and layers are formed by water carrying particles either up or down
Soil porosity
The amount of space between particles
Soil permeability
The ease at which gases and liquids can pass through the soil
Subsistence farming
Growing food for own families and communities
Cash cropping
Growing crops for the market
Commercial farming
Takes place on a large, profit-making scale, maximising yields per hectare
Extensive farming
Uses more land, low inputs, low outputs (hill sheep farming)
Intensive farming
Uses lots of energy and inputs for high outputs (rice farming, battery chicken farming)
