Zonal Soils Flashcards
What are the major components of soil?
Dead organisms,
living organisms,
water,
minerals,
air micro and macro nutrients- soils are a layer of unconsolidated [loose] material that develops at the boundary of the earth’s crust.
What determines soil type?
Parent material [rock type underneath]
Climate
Topography
Living organisms
Time
Why is soil important?
Sustains 95% of food production
Sustains plant and animal life - 1/4 of the planets biodiversity - diversity and productivity depends on the soil
Major source of pharmaceuticals
Cycling nutrients - critical role in the water, carbon, nitrogen and phosphorus cycle
Regulates water supply [used for irrigation]
Filters potential pollutants - minerals a microbes filter organic and inorganic pollutants
Physical stability and support - for plants and built environment
However, the level of soil degradation of estimated tp be at 33% globally, this has the potential to threaten food security and send many people into poverty.
How can soil be classified?
By horizons that can be seen [layers]
The ability to support plants and a natural environment
What are the soil Horizons?
Surface layers - Organic debris, partly decomposed [O Horizons]
Topsoil - Mineral particles mixed w. organic material [ A horizons]
Subsoil - Compounds draining from above accumulate [B Horizons]
Parent material - Partly weathered rock [C Horizons]
Bedrock - [R horizon]
ZONAL SOIL : RED/YELLOW LATOSOLS - Location and climate
Five degrees either side of the Equator, Brazil, South west Africa, India, Korea, Indonesia and Thailand
Tropical equatorial rainforest biome, where precipitation levels are high and temps are cool.
ZONAL SOIL : RED/YELLOW LATOSOLS - vegetation and soil fertility
Deciduous tropical rainforests tree, evergreen trees
Infertile - As most of the nutrients in ferrallisols are found in the organic material deposited in the lower soil levels
ZONAL SOIL : RED/YELLOW LATOSOLS - Agricultural systems and population density
shifting cultivation and grazing , black pepper and rubber plantations, mixed cropping
Population density 0-10 people per square kilometre in rainforest regions as high as 500 people per square kilometre is densely populated urban areas
ZONAL SOIL : RED/YELLOW LATOSOLS - threats
Deforestation on a massive scale, by felling bulldozing, and burning.
Land for settlement and associated infrastructure
Land for ranching, cash-cropping, and plantations
Hardwood timbers
Access for mineral exploitation
ZONAL SOIL : PODZOL - Location and climate
North America and Eurasia between the tundra to the north and temperate grasslands to the south. They are also found in the UK, Sweden and Denmark.
Areas with cool climates and in areas of sandy soil such as fluvioglacial outwash plains. Boreal zone and temperate zones
ZONAL SOIL : PODZOL - Vegetation and soil fertility
Coniferous evergreen trees such as spruce, fir and pine
Infertile - High acidity makes iron and aluminium compounds soluble. In Podzol soils theses accumulate in Horizon B to form a thin hardpan layer, which can be orange, this hinders drainage and creates waterlogging.
ZONAL SOIL: PODZOL - agricultural systems and population density
Sheep farming, Hunting moose, caribou and brown bear. Used for extensive grazing, breeding
4 people per square kilometre
