← Elaine Ingham · Research and publications
Protozoa: microscopic grazing that releases nitrogen
Consuming bacteria moves nutrients through the food web. Ingham explains the role of protozoa in this process.
Educational chapter published:
Small consumers of bacteria
The chapter introduces amoebae, flagellates and ciliates. Many feed mainly on bacteria. They need available food and water for movement, making moisture an important influence on their activity. [1]
How nitrogen returns to circulation
As protozoa consume bacterial biomass, they excrete nitrogen exceeding their needs as ammonium. Plants and other organisms can use this nitrogen. The process forms part of mineralization. [1]
Roots as meeting places
Food supplied by roots to bacteria indirectly supports their consumers. Protozoan activity therefore connects with rhizosphere conditions. A dry period or a vegetation change can alter the picture in a sample.
What deserves monitoring
In our training, observing movement goes alongside sample preparation and field moisture. We record handling methods and examination timing. These details help put sample comparisons on a common basis.
Sources and references
- Ingham, E.R. (1999). Soil Protozoa. Soil Biology Primer, unit E. USDA Natural Resources Conservation Service, Soil Quality Institute, PA-1637. August 1999. Original publication and study record
- Original full paper as PDF