Enough talk about bacteria! We want to see them in the flesh, so to speak. So Meredith went to Alley Pond in Queens and brought back a couple of buckets full of nice, black, smelly mud.
Many species of bacteria live in pond's mud and if you give them a good home, delicious food, and a warm environment, they grow like crazy. And that's exactly what we did today. We built bacteria hotels!
Each kid made one. It's called a Winogradsky column, after Sergei Winogradsky, a Russian microbiologist who came up with this brilliant idea.
How do you do it? It's quite straightforward. You put good bacteria food (newspapers as a source of carbon and eggs as a source of sulfur) in the bottom of a column (aka a soda bottle), you mix it with mud, you add more mud on top, you pour some pond water, and you cover it with plastic wrap. Then you wait a few weeks.
In this sealed system, bacteria and other microbes will reuse and recycle nutrients continuously. Over time, different species will separate into visible layers depending on how they use – or don't use – oxygen, light, and nutrients. Each bacterial species will find its habitat according to its needs and the colonies will be visible to the naked eye. If it doesn't sound brilliant... well it is!
It was a lovely day to be outside and we made nine nutrient-enriched columns, one for each kid, and a control column with no extra nutrients or water to compare to.
We'll see what happens. Stay tuned!
