The soil is home to the largest biodiversity on this planet; a fascinating world of micro-organisms. The most common being the bacteria, fungi and algae. However, they are not the only forms of biological and ecological significance, of equal importance are: protozoans, earthworms, nematodes and insects. This investigation will focus on a method of locating Amoebae, members of the protozoa.
Protozoa are unicellular, eukaryotic microorganisms. The Amoebae move
by means of pseudopodia. Many of them obtain their food by holozoic nutrition
characterized by direct feeding on microbial cells such as bacteria."It
has been estimated that one species of Amoeba requires 40,000 bacteria
per cell division. consequently bacteria must reproduce at a rapid rate
to keep pace with their predators".(Alexander,1967.p.108)
This information suggests that the protozoa population are important in limiting the bacteria population maintaining a balance in this highly populated soil habitat. The amoebae survive unfavorable conditions by forming cysts.
They are usually found near the surface of the soil in the upper 6 inches in soils that are warm, moist, and rich in organic matter as this encourages a high bacteria population.They tolerate a range of pH with a preference for acidity.
Since the soil is a complex habitat, with a rich biodiversity component;
collecting amoebae will also show other organisms coming out of the soil.
So this activity will lead to other investigations of the soil ecosystem.
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