Summary
Bacteria convert nitrogen through fixation, nitrification, assimilation and denitrification so organisms can use it.
In depth
Nitrogen gas is 78 percent of air but inert. Nitrogen fixation (Rhizobium, Azotobacter, lightning) makes ammonia; nitrifying bacteria convert ammonium to nitrite and nitrate; plants assimilate nitrate; denitrifying bacteria return N2. Haber-Bosch fertiliser production doubled the amount of fixed nitrogen entering ecosystems.
Fixation and nitrification support plant growth. Leaching of nitrate into water causes eutrophication. Denitrification returns N2 to the air and nitrous oxide, a greenhouse gas, is a by-product.
Example: waterlogged soils favour denitrifiers.
Frequently asked questions
What is Nitrogen Cycle?
Bacteria convert nitrogen through fixation, nitrification, assimilation and denitrification so organisms can use it.
Which area of biology covers Nitrogen Cycle, and how advanced is it?
Nitrogen Cycle is one of the 54 topics in Ecology. It is rated Beginner, so it suits learners who are starting out in biology. Related topics in this area include Decomposers, Eutrophication, Ecological Stoichiometry.
Can you give an example of Nitrogen Cycle?
Legumes in crop rotations restore soil nitrogen.
What should I learn before Nitrogen Cycle?
Nitrogen Cycle is a Beginner topic, so no earlier topic is required. Other Beginner topics in Ecology that pair well with it include Ecology, Ecosystem, Biotic and Abiotic Factors.
What topics are related to Nitrogen Cycle?
The closest topics to Nitrogen Cycle are Decomposers, Eutrophication, Ecological Stoichiometry, Primary Productivity. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Nitrogen Cycle?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Nitrogen Cycle. To practise the whole of Ecology, use the Ecology quiz.
How is Nitrogen Cycle different from Decomposers?
Nitrogen Cycle: Bacteria convert nitrogen through fixation, nitrification, assimilation and denitrification so organisms can use it. Decomposers: Bacteria and fungi that break down dead matter and recycle nutrients to the soil. Read both side by side and note what each one explains.
How should I study Nitrogen Cycle step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Decomposers and explain the difference aloud. Finally, take the Ecology quiz and come back to this page for any question you miss.