The Nitrogen Cycle
In 1772, Physician Daniel Rutherford discovered nitrogen. He removed oxygen and carbon dioxide from air and discovered that the residual gas does not allow living organisms and combustion to survive. Some other scientists among whom there were Carl Wilhelm Scheele and Joseph Priestly called nitrogen "burnt" air or air without oxygen. In 1786 Antoine Laurent de Lavoisier named nitrogen "azote" which means "lifeless". This term implied that this substance is the part of air that cannot support life on its own.
Ammonia is one of the most important nitrogen compounds. Ammonia can be produced during the Haber-Bosch process in which nitrogen reacts with hydrogen. The ammonia gas is colourless and has a pungent smell that can be liquefied into a nitrogen fertilizer. About 80 percent of ammonia is used as a fertilizer. Ammonia can also function as a refrigerant gas in plastic, textile, pesticide and dyeing industries.
Nitrogen is one of the most broadly distributed chemical elements among our planet. It can be found in the soil, air and living organisms. The soil has an insignificant amount of nitrogen, that is mainly salt of nitric acid. Protein substances and natural organic compounds also consist of nitrogen. The presence of nitrogen in nature is primarily connected with the activity of bacteria and algae because microorganisms extract nitrogen from the degradable waste.
Ammonia is one of the most important nitrogen compounds. Ammonia can be produced during the Haber-Bosch process in which nitrogen reacts with hydrogen. The ammonia gas is colourless and has a pungent smell that can be liquefied into a nitrogen fertilizer. About 80 percent of ammonia is used as a fertilizer. Ammonia can also function as a refrigerant gas in plastic, textile, pesticide and dyeing industries.
Nitrogen is one of the most broadly distributed chemical elements among our planet. It can be found in the soil, air and living organisms. The soil has an insignificant amount of nitrogen, that is mainly salt of nitric acid. Protein substances and natural organic compounds also consist of nitrogen. The presence of nitrogen in nature is primarily connected with the activity of bacteria and algae because microorganisms extract nitrogen from the degradable waste.
Nitrogen cycle in the environment
During the decomposition of organic substances, they turn nitrogen into ammonia. Nitrifying bacteria oxidizes ammonia to nitric acid. Nitric acid reacts with carbonates present in soil to form nitrate. However, during decomposition, some part of nitrogen is released into the atmosphere in a free state. Free nitrogen is emitted during combustion of organic compounds, burning logs, stone coal and turf. When faced with a shortage of oxygen, denitrifying bacteria uses nitrate to support respiration, and that is how free nitrogen is formed. The source of mineral nitrogen compounds are electric discharges in the atmosphere that create nitrogen oxide and activity of nitrogen bacteria that consume and process atmospheric nitrogen into nitrogen compounds. Nitrogen oxide reacting with water results in nitric acid that turns into nitrates in soil.
How to reduce the amount of nitrogen
In order to reduce the excessive amount of nitrogen in the environment one must consider sustainable agriculture, organic farming and raising the awareness of these environmental issues among farmers.
The organic waste (such as animal waste) would be a good solution to balance the nitrogen presence in the environment. Another important solution is to use slow-release fertilizers that have plastic coatings on them and to release nitrogen gradually throughout the growing season.
In August 2017, microbiologists at the University of Alberta in Canada and the University of Vienna in Austria discovered an ammonia-oxidizing microbe called Nitrospira inopinata.
According to the researchers, Nitrospira inopinata is an ammonium sponge. This microbe significantly outperforms almost every other type of bacteria and archaea (single-celled organisms) in the oxidation of ammonium in the environment. The microbe is an efficient oxidizer and it can produce less nitrous oxide in the process.
These findings that appeared in the scientific journal Nature could become a breakthrough in the climate change research and could reduce ammonium levels in the soil, water and atmosphere. However, in 2020, scientists questioned the bacteria’s ability to reduce nitric oxide to nitrous oxide.
The good news is that every one of us can reduce nitrogen footprint by choosing protein diets, such as vegetables, chicken and seafood instead of beef and lamb. Furthermore, a minimalist way of life can help us to reduce food waste as one can limit the number of purchases. Remember that if you reduce nitrogen footprint, you also reduce your carbon footprint.
An easy way to reduce the nitrogen in the environment is to plant more trees - Tree roots absorb nitrogen compounds as part of the natural nitrogen cycle...