Nitrogen

These flashcards cover essential terms and concepts related to nitrogen, its role in soil health, and processes affecting nitrogen cycling.

Nitrogen

A naturally occurring element essential for growth and reproduction in both plants and animals, comprising about 79% of the Earth’s atmosphere.

Anionic form

The form of nitrogen primarily found in soil, often in the form of nitrate.

Cationic form

The form of nitrogen that is ammonium in soil.

Nitrogen mineralization

The process of converting unavailable forms of nitrogen to available forms, changing organic nitrogen to inorganic nitrogen.

Nitrogen immobilization

The process of converting available forms of nitrogen to unavailable forms, changing inorganic nitrogen to organic nitrogen.

Nitrification

The biological oxidation of ammonium to nitrite followed by the oxidation of nitrite to nitrate.

Denitrification

The reduction of nitrates to gaseous nitrogen, which results in the loss of nitrate from the soil.

Ammonification

The process by which N-containing organic compounds are converted to ammonium compounds by microorganisms.

Nitrogenase

An enzyme that catalyzes the reduction of atmospheric nitrogen gas (N2) to ammonia (NH3).

C:N ratio

The ratio of carbon to nitrogen in organic material, important for determining nutrient availability for soil microorganisms.

Biological nitrogen fixation

The reduction of atmospheric nitrogen gas to ammonia by specific microorganisms.

Nitrate reductase

An enzyme that catalyzes the conversion of nitrate to nitrite and then to ammonia.

Ammonium toxicity

A condition that can occur when plants take up excess ammonium, potentially retarding growth and nutrient uptake.

Rhizobia

Bacteria that fix nitrogen in symbiosis with legume roots.

Luxury consumption

The uptake of nitrogen beyond what is needed for basic growth, often leading to nutrient imbalances.

Acid rain

Precipitation that contains higher than normal amounts of nitric acid, affecting nitrogen sources in the soil.

Nitrosomonas

A genus of bacteria involved in the first step of nitrification, converting ammonium to nitrite.

Nitrobacter

A genus of bacteria involved in the second step of nitrification, converting nitrite to nitrate.