Nitrogen is present in soil and in the atmosphere. As nitrogen goes through biological and chemical changes when it comes into contact with various temperatures, weather conditions, bacteria and other matter present in our ecosystem, it can be combined into living and nonliving material. The nitrogen cycle is a descriptive name given to the various processes that occur to form nitrogen and its derivatives as it is cycled through our environment. One of the forms nitrogen takes in soil is nitrate.
Nitrate is a derivative of nitrogen and is created when a nitrogen atom bonds with three oxygen atoms. Nitrate is commonly found in high concentrations in fresh water and estuaries and can cause algae blooms and fish kills. Nitrate is also a by-product of decomposing human and animal waste.
Nitrate is found in several abiotic, or inorganic, sources. Abiotic and inorganic are terms that mean non-living. Nitrate is found in lightning and soil, both of which are non-living, or abiotic.
Abiotic sources of nitrate contribute to the nitrogen cycle. Since human and animal waste contains nitrate, much of that nitrate is added to the soil during the waste disposal process. Lightening also contains a high concentration of nitrate; whenever lightening strikes, nitrate is released into the soil that the lightening hits. Most plants obtain the nitrogen they need in the form of inorganic nitrate from the soil. The nitrate is broken down in a process called denitrification to produce pure nitrogen, which plants use for life processes.