The Microbes Within

The soil beneath the boxwood revealed a host of microbes within the soil. The 10-3 diluted solution contained the most colonies and was the plate used to calculate the average number of microbes per gram of soil. Counting 72 individual colonies then multiplying by 10-3, we determined that within our soil sample there are 72,000 microbes per gram of soil. Incredible! Within one gram of soil there exist thousands of microbes. Imagine what you could find within a square foot underneath the boxwood! But this begs the question: are all of the microbes in the one gram of soil from the same species or is a wide array represented?

Simply observing the plates allows the deduction that more than one microbe species are present. As the solutions increased in dilution, the amount of microbes decreased which allowed for specimen isolation. There were various bacteria colonies ranging from yellow to creamy white, from lumpy to smooth. Furry fungi could be found on the 10-3, 10-4, and 10-5 diluted solution plates. Interestingly, the fungi on the 10-5 plate had a bright red hue. The 10-4 diluted solution on the Rose-Bengal agar plate only had one large specimen. Being convex, smooth, and creamy white, it's appearance was more similar to a striped boil than a microbial colony.

So why do these observations of various microbes matter? Though the soil underfoot does not always appear to be more than solid ground, the biodiversity within plays a vital environmental role. Think of soil as the support system for all living things existing above. Not only physical support, but also nutritional. Microbes within soil are the key recycler of organic material produced from organism living above the dirt and supply nutrients back to environment for consumption. They affect the acidity and sodicity of soil, which must be maintained for proper plant growth. These tiny organisms act as a filtration system, purifying water and other solutions that pass through soil. What is important to remember is that though microbes are small, they powerful environmental allies.

-Palmer Miller