Nitrogen

Nitrogen and nitrogen, symbol N constitutes the greatest element of the Earth 's atmosphere. The atomic number of nitrogen is nitrogen of group 15 (or Va) of the periodic table. Nitrogen was discovered by British doctor Daniel Rutherford in 1772 and was recognized as elemental gas by French chemist Antoine Laurent Lavoiser in 1776. Nitrogen is colorless, odorless, tasteless, nontoxic gas. It can be concentrated to a colorless liquid and it can be compressed into a colorless crystalline solid.

Nitrogen is the most important structural element of all organisms. There are plenty of nitrogen in the air, but animals and most plants can not fix atmospheric nitrogen. Nitrogen circulation mainly involves incorporating atmospheric gaseous nitrogen and organic nitrogen from dead plants and animals into available forms for higher plants. The shortage of suitable nitrogen-containing compounds is a major problem in maintaining soil fertility. Consequently, the conversion of nitrogen has attracted considerable attention from soil microbiologists. Higher plants usually require nitrogen in the form of nitrates, but ammonia and some organic nitrogen compounds are used to a lesser extent.

Human beings are involved in the nitrogen cycle in various ways, but not all of them are informative. One of the most important roles people play in the nitrogen cycle is the introduction of nitrogen fertilizer into the soil. Since nitrogen has a strong influence on plant growth, farmers are eager to add more nitrate, ammonium, or both to their crops. When the soil absorbs all the nitrogen it can hold, it eventually leaches - the process of removing water-soluble soil material. In particular, nitrate leaches from farmland to groundwater, streams and other surface water. This can lead to conditions of eutrophication, increased biological productivity, which is ultimately harmful to the ecosystem around the lake and other bodies of water. (For details on eutrophication, see biogeochemistry cycle.)

Nitrogen leaching is a serious ecological problem due to water pollution. Mineralization of soil organic nitrogen, especially nitrification of nitrogen fertilizer, is one of the main reasons for nitrogen enrichment in soil. Biological nitrification inhibition (BNI) has gradually become the main target for studying plant nitrification. Research has shown that plant nitrification inhibitor (NIS) is the first choice for soil nitrification control in recent years. For example, a biological nitrification inhibitor (BNIS) is an allelic chemical that can suppress nitrification of soil. Wheat Allelochemicals such as ferulic acid, p-hydroxybenzoic acid, hydroxamic acid, etc., act on soil microorganisms, suppress soil nitrification, reduce N 2 O emissions, increase nitrogen use efficiency, and reduce environmental pollution (Ma, 2005). Dietz et al

Advances in research on physiological and ecological mechanisms of allelopathic and allelopathic effects of agricultural crops