Long-lasting nitrogen fertilizer

ammonium nitrogen fertilizer, nitrate nitrogen fertilizer, amide nitrogen fertilizer are quick-acting fertilizer, after application into the soil part of the crop absorption, part decomposition or loss, reducing the economic benefits as fertilizer, but also pollution of the environment.
Since the 1940s, many countries in the world have been studying long-acting nitrogen fertilizer, the successful development of synthetic
organic
nitrogen fertilizer (e.g. formaldehyde, acetaldehyde, etc.), envelope fertilizer (such as sulfur urea, slow-acting inorganic fertilizer, long-acting ammonium carbide) and so on.Synthetic organic long-lasting nitrogen fertilizer is mainly a class of arginal fertilizer, urea and aldehyde reaction and the generation of poor water solubility polymer, it is generally under the action of
microorganisms
gradually decomposition, release ammonia and carbon dioxide. Among them, formaldehyde (codenium
UF) is more mature, in 1955 has been sold commercial fertilizer. One of the long-lasting nitrogen fertilizers considered promising is arganodehyde (isotin fork dihydrine, codenate IBDU), which has been sold since 1962. It is suitable for a variety of soils and different climates, the rate of release of effective nitrogen is related to the particle size of the product. At present, the production of fertilizer efficiency period of two months to more than 3 years of a variety of isodehyde. Some products are made of brick, called ultra-slow fertilizer, can continue to supply nitrogen for 3 to 5 years, can be used in forestry and urban greening. The nitrogen provided is almost 100% effective and free of residues.Envelope fertilizer with sulfur, paraffin, asphalt, plastic and other water-soluble particle fertilizer put on the coat, so that nitrogen slowly released. The most important of these is sulphur urea, coden
SCU. It provides nitrogen and sulfur. China's sulfur resources are poor, mainly developed with calcium magnesium phosphorus fertilizer envelope ammonium bicarbonate or urea long-lasting nitrogen fertilizer. The Nanjing Soil Research Institute of the Chinese Academy of Sciences has developed the above-mentioned envelope long-lasting nitrogen fertilizer.Ammonia, phosphoric acid and priceless metal elements (such as magnesium, iron, zinc, copper, manganese, etc.) are reacted to produce a general form of
NH
4 PO 4 .nH2O class of
compounds
(Me for dloride metal ions), which is a class of soluble inorganic nitrogen fertilizer. They are slightly soluble in water and soil solutions. Ammonium Phosphate magnesium (MgNH 4PO 4 ) is a white solid containing nitrogen
9%, phosphorus 12% and magnesium 15.5%. It is actually a kind of compound fertilizer, mainly used in fruit trees, lawns, flowers and so on.