Earth Science, HSus 2: Managing Resources (HS), HSus 4: Evaluating Solutions (HS), Human Sustainability, Interdependent Relationships in Ecosystems, IR 1: Carrying Capacity (HS), IR 1: Ecosystem Interactions (MS), IR 3: Ecosystem Stability (HS), IR 6: Human Impact Solutions (HS), Life Science

Rotifers Eating Bacteria to Clean Water

Foam-forming bacteria in activated sludge effectively reduced by rotifers in laboratory- and real-scale wastewater treatment plant experiments

SUMMARY: This article looks at using rotifers as a way to control a specific type of filamentous bacteria in wastewater treatment plants. Overgrowth of this bacteria leads to foam and inefficient break down of waste by other microorganisms. Experiments were first done at a laboratory-scale, then at real life scales. Researchers found that all the species of rotifers they used were very efficient at getting rid of filamentous bacteria, especially if these rotifers were purposely added into aeration tanks. This method could help wastewater treatment plants control unwanted bacterial growth in a more environmentally friendly manner.

LESSON COMMENTS: This is a great article to go with a microscopy lab looking at the different microorganisms in a pond. Rotifers and ciliates are easy to find and large enough that higher magnification is not necessary; depending on the source of the pond water, they may actually be able to see a sample with microorganisms similar to those found in wastewater treatment plants.

Environmental science classes studying ecosystem relationships, pollution, or researching eco-friendly ways to clean water would find this article useful. It’s a pretty easy read, so students could do the reading as a homework assignment.

Pajdak-Stós, A., Kocerba-Soroka, W., Fyda, J., Sobczyk, M., & Fiałkowska, E. (2017). Foam-forming bacteria in activated sludge effectively reduced by rotifers in laboratory- and real-scale wastewater treatment plant experiments. Environmental science and pollution research international, 24(14), 13004-13011.