N-n

Nature: It is the habitat confluence animal life, vegetable and mineral.
ecological niche: It is a broader term that habitat, since it designates not only the place where organisms live, but also the functional role they play as members of the community.
Nickel. chemical element of group VIII of the periodic table. Atomic number 28 and atomic mass 58.71. It is a white metal. It has industrial applications in alloys and as a catalyst.
Nitrates. NO3 ion- and its salts or salts of nitric acid, HNO3. They are nutrients that are easily assimilated by plants., so they are used as fertilizers. The contributions of nitrates to the sea and the water of rivers and lakes favor the growth of algae (eutrophication). 
Nitrite. NO2 ion- and its salts or salts of nitrous acid, HNO2. They have industrial applications. They are toxic substances from which nitrosamines can be formed., that are carcinogenic.
Ammoniacal nitrogen. Combined nitrogen in the form of ammonia (NH3) or ammonium (NH4+). Ammonia and ammonium are gases that are produced naturally by microbial fermentations of nitrogenous products., for example in the decomposition of proteins or urea.
Kjeldahl Nitrogen. Amount of nitrogen determined by the Kjeldahl method. It includes nitrogen from organic compounds and ammoniacal nitrogen.
Total nitrogen. In an organic sample, the nitrogen content measured as the difference between Kjeldahl nitrogen and ammoniacal nitrogen.
Nitrogen. Chemical element of group V of the periodic table of atomic number 7 and atomic mass 14.007. Its diatomic molecule is a chemically inert gas that constitutes the 80% by weight of the atmosphere. It is one of the five macroelements found in organic matter. It is an essential component in nitrogen fertilizers. It is worth highlighting the ability of leguminous plants to fix atmospheric nitrogen thanks to symbiosis with bacteria of the Rhizobium genus.. Symbol N.
Equivalent sound level measured in decibels A. Leq dB(A). Weighted continuous acoustic pressure unit using an A filter that allows the same frequency pass as the human ear.
Equivalent acoustic level. Leq. Continuous acoustic pressure unit.
Sound exposure level. Constant sound level in one second that had the same energy as the noise considered in a period of time (expressed in decibels A). (S.E.L.). 
Background noise level. It represents the noise level that is reached or exceeded by the 90% weather (L90), without the noise emitting source being studied being in operation.
Piezometric level. Groundwater level determined with a piezometer.
scientific name. Latin name with which the species is designated, composed of two terms. The name of the genus appears first., which must be written in capital letters and then the specific. Current scientific names have their origins in Linnaeus. (tenth edition of Systema Naturae, 1758), inventor of binomial nomenclature. Currently, scientific nomenclature is subject to international regulation. (International Code of Scientific Nomenclature).