Protozoa. Protozoa play important roles in environmental food web dynamics. They graze on bacteria thus regulating bacterial populations, they part-take in wastewater treatment processes, they maintain fertility in soil by releasing nutrients when they digest bacteria.

Why are protozoa important to humans?

They are the ultimate decomposers in nature, as they feed on bacteria and fungi, which decompose dead organic matter. They are, thus, useful in the treatment of sewage. 3. Some protozoans live in the body of other organisms and help them.

What is a protozoan and why are they important?

Protozoans play important roles in the fertility of soils. ... Protozoans also excrete nitrogen and phosphorus, in the form of ammonium and orthophosphate, as products of their metabolism, and studies have shown that the presence of protozoans in soils enhances plant growth.