Soil Science

Sedentary soil is soil remaining on the rock from which it has developed or on which they are situated.
Black soil is an example of sedentary soil. Black soils are mineral soils that have a black surface horizon, enriched with organic carbon. It is the third major group of soil found in India.

Geological erosion is also known as Natural erosion. It is the action of surface processes that removes soil, rock or dissolved material from one location of the Earth’s crust, and then transports it to another where it is deposited by the action of wind or water.
The geological type of erosion contributes to the formation of soils and their distribution on the earth’s surface.

Ultisols are strongly leached, acid forest soils with relatively low native fertility. They are found primarily in humid temperate and tropical areas of the world.
Alfisols are moderately leached soils that have relatively high native fertility. These are primarily found in temperate humid and subhumid regions of the world.
Alfisols have at least 35% base saturation, meaning calcium, magnesium, and potassium are relatively abundant. This is in contrast to ultisols, which are the more highly leached forest soils having less than 35% base saturation. That means Ultisol is comparable with alfisol except for having low BS% where BS is base saturation.

Fe-EDDHA is the Fe-chelate suitable for application to crops grown on calcareous soils. This chelated iron helps in correcting iron deficiency in flowers, vegetables, shrubs, and trees.
EDDHA is a chelate that protects nutrients against precipitation in a wide pH range of 4 – 9. And the availability of iron to plants is reduced through preci[piatation of iron at high pH, or by high concentrations of phosphorus.

Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. It is a common material, making up to 45% of average modern mud, found in many river deltas and as wind-deposited accumulations.
Silt is made up of rock and mineral particles that are larger than clay but smaller than sand. It ranges from 0.002 to 0.05 mm in diameter.

Basic slag is a byproduct of the steel industry low in silica and high in base-forming oxides that are used in the basic process of steelmaking and that is subsequently useful as a fertilizer.
It is mostly citrate soluble fertilizers, quicklime and magnesite introduced for refractory protection, neutralizing the alumina and silica separated from the metal.

Endopedon is a diagnostic horizon characterized by the accumulation of aluminum and organic matter with or without iron. And the endepedon with high bulk density is known as Fragipan.
A Fragipan is a diagnostic horizon in USDA soil taxonomy. They are altered subsurface soil layers that restrict water flow and root penetration.

Leucoxene is amorphous hydrous titanium oxide. It is a fine granular alteration product of titanium minerals, a mineral consisting of rutile and partly of anatase or sphene occurring in some igneous rocks and iron ore deposits.
It varies in colour from yellow to brown

Nitrogen-fixing bacteria are prokaryotic microorganisms that are capable of transforming nitrogen gas from the atmosphere into fixed nitrogen compounds that can be easily available for plants for absorption like ammonia.
Bacteria can be anaerobic like Clostridium and aerobic like Azatobacter.
Clostridium is a non-symbiotic, anaerobic nitrogen fixing bacteria that fix nitrogen in the absence of oxygen.

Urea is an organic compound and more than 90% of world industrial production of urea is destined for use as a nitrogen-release fertilizer. Urea breaks down in the soil to give ammonium.
The efficiency of urea can be increased by using neem cake with it, as it reduces the rate of nitrification thus efficiency is increased.