The itrogen Cycle By: Rachel Brewer Kaci Kelley-Brown Jennifer Moats Dolleen Wiltgen
What is nitrogen?
Periodic Table itrogen is in the onmetals Group
Where is nitrogen found in the environment?
The largest single source of nitrogen is in the atmosphere. itrogen makes up 78% of our air!
What happens to atmospheric nitrogen ( 2 ) in the nitrogen cycle?
Atmospheric nitrogen is converted to ammonia or nitrates. Atmospheric itrogen ( 2 ) Ammonia (H 3 ) itrogen combines with Hydrogen to make Ammonia itrates (O 3 ) itrogen combines with Oxygen to make itrates
Why does atmospheric nitrogen need to be converted?
It is one of nature s great ironies itrogen is an essential component of DA, RA, and proteins the building blocks of life. Although the majority of the air we breathe is nitrogen, most living organisms are unable to use nitrogen as it exists in the atmosphere!
How does atmospheric nitrogen get changed into a form that can be used by most living organisms?
By traveling through one of the four processes in the itrogen Cycle! (4) Denitrification (1) itrogen Fixation itrogen Cycle (3) itrification (2) Ammonification
The first process in the nitrogen cycle is itrogen Fixation! (1) itrogen Fixation itrogen Cycle
What is nitrogen fixation and what does it mean to say nitrogen gets fixed?
itrogen Fixation is the process that causes the strong two-atom nitrogen molecules found in the atmosphere to break apart so they can combine with other atoms. Oxygen Hydrogen Hydrogen Oxygen itrogen gets fixed when it is combined with oxygen or hydrogen.
There are three ways that nitrogen gets fixed! (a) Atmospheric Fixation (b) Industrial Fixation (c) Biological Fixation Bacteria
Atmospheric Fixation (Only 5 to 8% of the Fixation Process) The enormous energy of lightning breaks nitrogen molecules apart and enables the nitrogen atoms to combine with oxygen forming nitrogen oxides ( 2 O). itrogen oxides dissolve in rain, forming nitrates. itrates (O 3 ) are carried to the ground with the rain. Lightning fixes itrogen! ( 2 O) (O 3 ) O itrogen combines with Oxygen itrogen oxides forms itrogen oxides dissolve in rain and change to nitrates Plants use nitrates to grow!
Industrial Fixation Under great pressure, at a temperature of 600 degrees Celcius, and with the use of a catalyst, atmospheric nitrogen ( 2 ) and hydrogen are combined to form ammonia (H 3 ). Ammonia can be used as a fertilizer. H3 (H 3 ) H Industrial Plant combines nitrogen and hydrogen Ammonia is formed Ammonia is used a fertilizer in soil
Biological Fixation (where MOST nitrogen fixing is completed) There are two types of itrogen Fixing Bacteria Free Living Bacteria ( fixes 30% of 2 ) Symbiotic Relationship Bacteria ( fixes 70% of 2 )
Free Living Bacteria Highly specialized bacteria live in the soil and have the ability to combine atmospheric nitrogen with hydrogen to make ammonia (H 3 ). H H 3 Free-living bacteria live in soil and combine atmospheric nitrogen with hydrogen (H 3 ) itrogen changes into ammonia Bacteria
Symbiotic Relationship Bacteria Bacteria live in the roots of legume family plants and provide the plants with ammonia (H 3 ) in exchange for the plant s carbon and a protected home. Legume plants H 3 Roots with nodules where bacteria live itrogen changes into ammonia.
Most atmospheric nitrogen ( 2 ) is fixed and changed to ammonia (H 3 ). Ammonia is highly toxic to many organisms. Can plants use ammonia?
Very few plants can use ammonia (H 3 ) (1) itrogen Fixation (2) Ammonification but, fortunately the second process Ammonification can help!
What is ammonification?
Ammonification: Bacteria decomposers break down amino acids from dead animals and wastes into nitrogen ammonium. Bacteria decomposers break down amino acids into ammonium
Why is ammonification necessary?
Because plants cannot use the organic forms of nitrogen that are in the soil as a result of: (1) wastes (manure and sewage) (2) compost and decomposing roots and leaves
How does ammonification occur?
Microorganisms convert the organic nitrogen to ammonium. The ammonium is either taken up by the plants (only in a few types of plants) or is absorbed into the soil particles. Ammonium (H 4 ) in the soil is stored up to later be changed into inorganic nitrogen, the kind of nitrogen that most plants can use. Bacteria converts organic nitrogen to ammonium (H 4 ) Bacteria Ammonium (H 4 ) is used by some plants Ammonium (H 4 ) is stored in soil.
What happens to ammonium (H 4 ) stored in the soil?
It travels through the third process of the nitrogen cycle called itrification! (1) itrogen Fixation (3) itrification (2) Ammonification
itrifying bacteria in the ground first combine ammonia with oxygen to form nitrites. Then another group of nitrifying bacteria convert nitrites to nitrates which green plants can absorb and use! itrifying bacteria in soil combine ammonia with oxygen Ammonia changes to nitrites itrifying bacteria in soil convert nitrites to nitrates Ammonia itrites itrates (H 3 ) (O 2 ) (O 3 ) Plants absorb nitrates and grow!
How does nitrogen reenter the atmosphere in the nitrogen cycle?
Through the fourth process called denitrification! (4) Denitrification (1) itrogen Fixation (3) Ammonification (2) itrification
What does denitrification do?
Denitrification converts nitrates (O 3 ) in the soil to atmospheric nitrogen ( 2 ) replenishing the atmosphere. itrogen in atmosphere ( 2 ) itrates (O 3 ) in Soil
How does the denitrification process work? itrates in soil
Denitrifying bacteria live deep in soil and in aquatic sediments where conditions make it difficult for them to get oxygen. The denitrifying bacteria use nitrates as an alternative to oxygen, leaving free nitrogen gas as a byproduct. They close the nitrogen cycle! itrogen in atmosphere closes the nitrogen cycle! ( 2 ) (O 3 ) Denitrifying bacteria live deep in soil and use nitrates as an alternative to oxygen making a byproduct of nitrogen gas.
Other ways that nitrogen returns to the atmosphere Emissions from industrial combustion and gasoline engines create nitrous oxides gas ( 2 O). Volcano eruptions emit nitrous oxides gas ( 2 O).
2 (a) (b) 2 O (4) Denitrification (1) itrogen Fixation (c) itrogen Cycle (3) itrification (2) Ammonification Ammonia is converted to nitrites and nitrates. O 3 itrates in Soil H 3 Organic nitrogen is converted to ammonium.
2 (a) (b) 2 O (4) (1) (c) itrogen Cycle (3) (2) O 3 Ammonia is converted to nitrites and nitrates. itrates in Soil H 3 Organic nitrogen is converted to ammonium.
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