What is the sulfur cycle?
The sulfur cycle is the circulation of sulfur in various forms through nature.
Sulfur occurs in all living matter as a component of certain amino acids. It is abundant in the soil, in proteins and, through a series of microbial transformations, ends up as sulfates usable by plants.
The plants are eaten by herbivores (plant eaters) which in turn are eaten by carnivores (meat eaters). When animals and plants die, the cycle begins again.