SUMMARY: This is a short review of the role protozoa play in wastewater treatment plants. Most of the protozoa are ciliates and they graze on bacteria, excrete nitrogen, phosphorus, and carbon waste, and are used as indicators of water quality. Toxins such as heavy metals, salts, and other chemicals used to disinfect water affects different ciliates in different ways; some are more sensitive while others can withstand higher levels of toxins.
LESSON COMMENTS: This article covers so many different topics that I teach in Environmental Science class: the rhizosphere, nitrogen/phosphorus/carbon cycles, ecosystem relationships, pollution, water treatment plants, sewage treatment, and water resources. There are several types of protozoa, ciliates mostly, listed at the beginning that would be useful for identification if you’re looking at pond samples; just type in the name of the organism into Google Images! Overall, it is a fairly easy article to understand and teachers can assign different sections of this paper for homework/reading assignment.
Madoni, P. (2011). Protozoa in wastewater treatment processes: A minireview. Italian Journal of Zoology,78(1), 3-11. doi:10.1080/11250000903373797