NEW
Font size
WorksheetsTropical Soils
Total questions: 23
Worksheet time: 12mins
Key terminology:
the organic component of soil, formed by the decomposition of leaves and other plant material by soil microorganisms
Sol biota
Catena
Humus
Regolith
the breaking down of rocks, soil, and minerals in situ
Key Terminology:
drain away of solubles from the soil by the action of percolating liquid, especially rainwater.
Percolation
Infiltration
Through flow
Leaching
Key terminology:
a reddish clayey material, hard when dry (concretion), forming a topsoil in some tropical regions
Red and Brown earth
Oxisol
Laterite
Laterization/hydrolysis
Key terminology:
Small compounds or nutrient cations, are moved out of the soil profile by leaching. The two exceptions to this process are iron and aluminum oxides. What are they called?
Red and Brown earth
Oxisol
Laterite
sesquioxides
Key terminology:
The B horizon of the soil for tropical red earth (savannah) is enriched with calcium carbonate from water moving downward through the soil, or upward by capillary action of water from below.
Capillary action
Calcification
Carbonation
Hydrolysis
the upward movement of water through the soil against the force of gravity.
Oxisol Soil
Rainforest
Savanna
Depth of rainforest soil.
2-4m
up to 15m
up to 30m
up to 42m
The depth of Tropical red and brown earth (Savanna) soil.
under 1m
2-4m
4-5m
5-10m
Tropical climates influence soil by...
Why are rainforest soils so infertile?
Rapid breakdown of leaf litter
Erosion of soil removes organic material
Leaching strips organic and mineral material leaving only iron and aluminium oxides
Temperatures are not conducive for nutrient recycling
Why do Savanna soils have laterite layers?
Due to large diurnal temperature range
Due to many periods of wetting then drying
Due to capillary action
Due to the wet season
What is the difference between leaching and eluviation?
Leaching involves insoluble whereas eluviation only refers to soluble
Leaching involves only humus whereas eluviation includes oxides
Leaching involves soluble whereas eluviation includes insoluble
Leaching involves downwards movement whereas eluviation involves upwards movement
What is the difference between eluviation and illuviation?
Eluviation is the washing down of minerals whereas illuviation is the location where those minerals are re-deposited.
Illuviation is the washing down of minerals whereas eluviation is the location where those minerals are re-deposited.
Which is true of the tropical rainforest (Af)?
Precipitation exceeds evapotranspiration
Evapotranspiration exceeds Precipitation
Which is true of the Savannah (Aw)?
Precipitation exceeds evapotranspiration
Evapotranspiration exceeds Precipitation
Key terminology:
Small compounds or nutrient cations, are moved out of the soil profile by leaching. The two exceptions to this process are iron and aluminum oxides. What is this process called?
Red and Brown earth
Oxisol
Laterite
Laterisation
