Soil Types and Properties for Agriculture

Oxisols are not a major soil type, but rather a suborder of Ultisols.

Mollisols are characterized by a thick, dark surface horizon rich in organic matter, which is formed under conditions of moderate rainfall and temperature.

Alfisols are characterized by a reddish or brownish color and a high content of iron oxides, which are formed under conditions of moderate rainfall and temperature.

Ultisols are characterized by a low pH and a high content of aluminum and iron oxides, which are formed under conditions of high rainfall and temperature.

Histosols are characterized by a high content of organic matter and are often found in wetlands, where they are formed under conditions of poor drainage.

Spodosols are characterized by a light-colored surface horizon and a subsoil that is rich in clay, which is formed under conditions of high rainfall and cool temperatures.

Vertisols are characterized by a dark-colored surface horizon and a subsoil that is rich in calcium carbonate, which is formed under conditions of high rainfall and temperature.

Andosols are characterized by a dark-colored surface horizon and a subsoil that is rich in volcanic ash, which is formed under conditions of high rainfall and temperature.

Saline soils are characterized by a high content of salt and are often found in arid and semi-arid regions, where they are formed under conditions of poor drainage and high evaporation.

Sodic soils are characterized by a high pH and a high content of sodium ions, which are formed under conditions of poor drainage and high evaporation.

Alkaline soils are characterized by a high pH and a high content of calcium carbonate, which are formed under conditions of low rainfall and high evaporation.

Acidic soils are characterized by a low pH and a high content of hydrogen ions, which are formed under conditions of high rainfall and low evaporation.

Soil texture is the most important soil property for determining the suitability of a soil for agriculture, as it affects the soil's ability to hold water and nutrients, as well as its drainage and aeration.

Organic matter content is the most important soil property for determining the soil's ability to hold water and nutrients, as it increases the soil's cation exchange capacity and water-holding capacity.

Soil structure is the most important soil property for determining the soil's drainage and aeration, as it affects the soil's porosity and permeability.