Suminder Kaur, Academic content writer at Edumarz
78% of our atmosphere consists of nitrogen.
A part of important molecules such as proteins, nucleic acid (DNA and RNA) and vitamins are made up from nitrogen.
The nitrogen cycle is a process through which atmospheric nitrogen is converted between its various chemical forms.
This transformation can be carried through both biological and physical process.
There are different forms of nitrogen : Ammonia, nitrate, nitrite, nitrous oxide and nitric oxide – these are all organic forms of nitrogen
inorganic= form of nitrogen – nitrogen gas.
Nitrogen cycle consists of many steps.
Atmospheric nitrogen can not be used as such by many organisms.
Microorganisms play a very important role in this process.
NITROGEN FIXATION
The nitrogen cycle begins with this phase. The conversion of ambient N2 to ammonia characterizes this stage (NH3). Bacteria such as Azotobacter and Rhizobium play a big part in this.
These bacterias are present in the roots of leguminous plants and convert nitrogen to ammonia.
Nitrogen fixation may take place in a variety of methods, including air fixation (which requires lightning), industrial fixation, and natural fixation (manufacturing ammonia under high temperature and pressure conditions).
NITROGEN ASSIMILATION
Plants may take nitrogen through their roots once nitrogen has been fixed in the soil. Assimilation is the term for this absorption process.
AMMONIFICATION
Another process by which ammonia can be produced.
Some bacteria break down organic remnants of plants and animals in the soil, releasing ammonia into the soil. These microbes exploit the dead and waste stuff as food, releasing ammonia into the soil.
NITRIFICATION
This process happens in two stages.
The conversion of NH3+ to NO3- is the initial stage (nitrates). In the soil, bacteria such as Nitrosomonas and Nitrococcus convert NH3 to NO2-, whereas Nitrobacter transforms NO2- to NO3-. These transformations provide energy to the bacterium.
DENITRIFICATION
It is the reverse of nitrification.
It happens in the soil’s deep layers, where microorganisms convert NO3- to N2 and other gaseous chemicals such as NO2. Because there is no oxygen in the deep layers of the soil, the soil bacteria utilize nitrogen molecules instead of oxygen.
IMPORTANCE OF NITROGEN CYCLE
The nitrogen cycle, as we all know, is responsible for bringing inert nitrogen from the air into the metabolic processes of plants and eventually to mammals.
Plants require nitrogen to make chlorophyll, hence the nitrogen cycle is critical to their survival.
The bacteria aid in the decomposition of decaying animal and plant debris during the ammonification process. This contributes to the natural cleansing of the environment.
Nitrates and nitrites are released into the soil as a result of the nitrogen cycle, which serves to replenish the soil with nutrients needed for agriculture.
As plants utilize nitrogen for their metabolic operations, animals acquire the nitrogen and nitrogen molecules from plants. Nitrogen is required since it is a component of the cell’s constitution. Animals are able to use nitrogen in the air because of the nitrogen cycle.
