Tropical Red Soils Latosols Zonal Soils of Equatorial

Tropical Red Soils Latosols

Zonal Soils of Equatorial Regions • Occur in the continents of South America, Africa and South Asia. • They are found near the equator. • For example in Brazil. • These countries all have an equatorial climate, that is very warm and very wet. • Called Latosols.

Characteristics of Latosols • • Low humus Heavy leaching Red colour Sometimes can have a brick like surface. • Short nutrient cycle • Can support very rich vegetation.

Causes of Characteristics…. • Low humus content is • The nutrient cycle is due to the rapid short because there is breakdown of organic fast plant growth and material due to the rapid decomposition. very hot and very wet This means humus is climate. formed and used before leaching occurs. • Leaching is intense, only iron and aluminium compounds remain, this gives soil its red colour.

Main Process Involved Laterisation

Laterites • Loose topsoil is eroded. • Iron and aluminium layers are exposed. • The high temperatures bake this into a hard brick like surface. • This surface cannot be cultivated. • It is known as a laterite.

Latosol Soil Profile

Latosol Soil Profile • O Horizon; A lot of organic matter, rapid decomposition. • A Horizon; Very thin layer due to short nutrient cycle. • B Horizon; Very deep, intense leaching. • C Horizon; Parent rock.

Uses of Latosol Soils • In many areas with latosol soils there are tropical rainforests. • The soil type can be an obstacle to the development of profitable agriculture. • If forest or vegetation is removed the soil can become infertile within a couple of years.

Exam Questions • Compare and contrast the characteristics of any two soil types which you have studied. (80 marks) – Characteristics; Colour, Texture, Structure, Humus, PH Value, Water content, Fertility. – Also contrast the processes causing these characteristics, climate, locations and uses.