Nutrients Nitrogen: General information
It is the most important nutritive element for plants and living organisms in general, since it is fundamental for the constitution of proteins, nucleic acids and other cellular constituents.
It is found in large quantities both in the rocks and in the atmosphere, of which it constitutes about 78%; unfortunately, however, it is one of the most difficult elements to find for living organisms, since it can only be absorbed if it takes on particular chemical forms. Nitrogen enters the biological cycle basically through plants, which absorb it directly from the soil; absorption by plants can only take place if the nitrogen is in the form of nitric ion or ammonium, whereas nitrogen is usually largely in gaseous form.
To be used then the nitrogen must be "fixed"; the nitrogen fixation process takes place fundamentally through micro-organisms that transform nitrogen gas into nitric ions or ammonium ions.
Some micro-organisms that take part in the nitrogen fixation process live in symbiosis with some plants, such as legumes, which receive nitrogen from bacteria present around their roots; the cultivation of these particular plants helps to make the land more fertile. Nitrogen ammonium ions, once fixed by microorganisms, become available for the plants, otherwise they become fixed in the ground, remaining available for a long time. Many plants can absorb both ammonium ions and nitric ions through the roots, but nitrate ions have the disadvantage of being very easily washed away by water, quickly ending up in watercourses. It is therefore essential that in fertile soils there is a good percentage of nitrogen fixed in ammonium ions, so that it can be used by plants over time. Furthermore, nitrogen in the form of nitric ion also has the defect of being harmful to humans, and also to the ecosystems of rivers and lakes.
It is therefore advisable to use good nitrogen improver products, to add them to deficient soils, paying attention to the recommended doses on the packages, remembering that also the substances used as fertilizer are external elements that we add to the environment, and that therefore have useful effects, but they can have undesirable effects if used thoughtlessly.
Nitrogen deficiency is manifested by a slow growth of the shoots, a general situation of stunted development of the plant and a pale green coloring of the basal leaves.
The deficiency occurs initially in the basal leaves and then appears also in the younger / apical leaves.
The most demanding plants in Nitrogen are the green ornamental plants, the conifers, the evergreens like the magnolia, the hedges, the lettuces, the aromatic herbs and all the plants in the initial stages of growth.
In fact, the nitrogen added immediately serves to make new shoots and numerous leaves, of an intense green color.
The nitrogen is present in fertilizers associated with other elements, such as phosphorus and potassium, forming the classic NPK fertilizers ...
In the composition it is found cited as a percentage of total Nitrogen (N).
The various types of nitrogen present (nitric, ammoniacal, urea and organic) must also be present by law.
Here is an example of the nitrogen composition of a fertilizer in a soluble powder fertilizer NPK 20.20.20.Nitrogen (N) total 20%
of which: Nitric nitrogen 5%
Ammoniacal nitrogen 6.4%
Urea nitrogen 8.6%
This label reads as follows: for every 100 grams of Asso di Fiori, 20% consists of Nitrogen, subdivided into Nitrica (5%), Ammoniacal (6.4%) and Ureica (8.6%) ).