Question

Differentiate between the following:

Nitrogen cycle and Phosphorus cycle

Answer 1

Basis of Difference	Nitrogen cycle	Phosphorus cycle
Type of cycle	It is a gaseous cycle whose main reservoir is the atmosphere.	It is a sedimentary cycle whose main reservoir is rocks and natural phosphate deposits.
Atmospheric input	Atmospheric input of nitrogen through rainfall is much more.	Atmospheric input of phosphorus through rainfall is very small.
Gaseous exchange	There is a large amount of gaseous exchange of nitrogen between organisms and the environment.	Gaseous exchange of phosphorus between organisms and the environment is negligible.
Source of nutrient	Nitrogen is obtained mainly by biological, industrial, and lightning fixation from the atmosphere.	Phosphorus is obtained mainly by weathering of phosphorus-containing rocks and deposits.
Forms used by plants	Plants use nitrates from the soil.	Plants use soluble orthophosphate from the soil solution.
Involvement of microbes	Many bacteria are involved, such as Rhizobium, Nitrosomonas, Nitrobacter, and Pseudomonas.	Very few bacteria are involved, such as phosphatising bacteria.