Which organisms make up the plankton community in freshwater lakes?

In freshwater lakes, the plankton community is composed of three primary groups: phytoplankton, zooplankton, and microbes.1

Phytoplankton

These are microscopic, photosynthetic organisms that serve as primary producers in the lake's upper layers (the photic zone). They include:1
* Algae: Specifically green algae, diatoms, and blue-green algae.2
* Other forms: True flagellates are also common components of freshwater phytoplankton.2

Zooplankton

These are small, animal-like organisms that drift with water currents. In freshwater environments, they include:31
* Rotifers: These can be present in vast numbers, particularly during warmer seasons.4
* Protozoans: Various single-celled organisms that function as consumers within the ecosystem.31
* Crustaceans: Often considered the most important members of the zooplankton, these serve as a vital food source for larger animals.34

Microbes

The plankton community also incorporates various microbes, including bacteria, which play essential roles as decomposers within the trophic network of the lake.1

It is important to note that the composition of these communities can vary significantly based on geographic location and seasonal changes.15