What have you done for 78% of your atmosphere today?I guess we have all heard about the element Nitrogen. But then how much do you really know about its importance?Nitrogen is one of the most important element to both plants, animals and even us. Do you know about 78% of the world’s atmosphere is actually Nitrogen? It exists in its gaseous form is called a gas called Nitrogen ga(N2) in the atmosphere. This means if you have been referring to air as just oxygen, then I think you should have a rethink.Some of us take Mr. Nitrogen for granted. Every living thing (including you, yes you!) actually depends on Nitrogen for its growth, functioning and repair of every physiological activities. Mr. Nitrogen actually is a vital component of our bodies. Its atom is found in all proteins and DNA. But then, Mr. Nitrogen cannot be used by us if it is just lying around occupying our ‘air space’. This means Nitrogen in its pure form has to be converted into a form that is beneficial to us. Plants and animals (including us) do not have the capability of converting Nitrogen gas into the form we can use. This is because the process requires some enzymes that are not present in plants and animals. With this in mind, how come we still have quite a lot of Nitrogen in our DNA and proteins? This is made possible by a process called ***Nitrogen Fixation***Nitrogen Fixation is a process whereby the nitrogen found in our atmosphere is converted into useable forms for plants. Pure nitrogen is converted to useable compounds via three processes. ## Natural ProcessThe natural process of Nitrogen fixation involves lightning. When lightning strikes, large energy is released. This energy breaks down the make-up of this pure nitrogen found in our atmosphere and causes their atoms to form a bond with oxygen in the air giving rise to **Nitrogen Oxides**. Nitrogen oxides dissolve in rain to form nitrates that falls back to the earth when it rains. ## Chemical Process Some industries convert the pure nitrogen to some useable compounds. These industries make use of atmospheric nitrogen together with hydrogen and expose them to a very high temperature and pressure giving rise to ammonia (NH3). This can be applied as fertilizers or passed through more processes to form urea and ammonium nitrate (NH4NO3). ## Biological ProcessBacteria and other single-celled prokaryotes are the chief nitrogen fixers. They are able to do this because of the presence of an enzyme called *Nitrogenase*. The whole process can be illustrated in the equation belowIn simpler terms, the atmospheric nitrogen is captured by Nitrogen-fixing microbes or other nitrogen fixers and then converted to ammonia (NH3) . This leads to the next step… ***Assimilation***In the assimilation step, Ammonia is used up by plants to make organic molecules such as; proteins and other nitrogen compounds.Plants do so by absorbing nitrates from the soil using their root hairs. The nitrates absorbed by plants is reduced to nitrites. This is further reduced to ammonium ion which is incorporated into amino acids, nucleic acids and chlorophyll.Some plants that have a symbiotic relationship with rhizobia use a different form. They assimilate nitrogen as ammonium ions straight from the nodules. Sometimes, these plants just give their amino acids to the symbiotic bacteria which adds Northern to it and return it to the plants. When we and other animals consume plants, we take in these organic molecules such are either taken up by our bodies or broken down into smaller molecules and then excreted as waste. An example is urea usually found in our urine. This excreted nitrogen in addition to the nitrogen released when plants and animals decay, is in organic form. This nitrogen compounds are acted upon by putrefying bacteria which releases them in the form of ammonia and ammonium compounds. Nitrifying bacteria acts on the ammonia and ammonium compounds converting them to nitrates and nitrites in a process known as Nitrification. This is a very important step the ammonia gas they convert is actually very harmful to plants. Denitrification comes in next. This is where the nitrates in the soil is converted back to our pure Nitrogen gas or atmospheric nitrogen and then the cycle is repeated all over again. ## How do we interfere in this whole process? Like earlier stated, nitrogen is vital to our existence and that of plants. But then, some of our activities interfere with the nitrogen cycle which is causing damage to our ecosystem.One way we are doing this, is the increased use of nitrogen fertilizers. Fertilizers helps our crops to grow well but then, they also increase the rate of denitrification. This means more nitrates are being changed to pure nitrogen gas at a higher rate. This in addition to leaching introduces high amount of nitrogen into groundwater. Excess nitrogen in our groundwater is no good at all, as this spreads to our lakes, rivers and steams causing eutrophication. This nitrogen-filled water causes high proliferation of algae and other water plants.Just in case you do not know, this means depleted oxygen in water and death of water animals. Like I said, no good. Breeding livestock also introduces nitrogen into water bodies. Their waste product is filled with large amounts of ammonia which contains nitrogen. They get into the soil and then into our groundwater. Other ways we are obstructing the nitrogen cycle is through the burning of fossil fuels, bush burning, leaching of our septic tank and sewage waste. I guess Mr Nitrogen is pretty pissed with us. Remember those plants I earlier mentioned are involved in the absorption of nitrates? They are leguminous plants. Such as peanuts, lupins, and beans etc. Continuous cultivation of such, therefore is beneficial to the nitrogen fixation process. This means, plant more than you consume. Show a little concern for our ecosystem by planting a legume today.