Let me just start out by saying I have TONS of respect for
all the cool things Sergei Winogradsky did for science. He was a Russian
scientist born in 1856 and is the founder of modern microbiology. Sergei used a columns, later called the
Winogradsky Columns, to watch the interactions of different groups of bacteria
over time and under different environmental conditions; lots of hydrogen
sulfide gas, lots of nitrogen, extra carbon. He also looked at how bacteria
colonies changed over time as organic and inorganic compounds were used up.
You have probably seen a Winogradsky column in some nature
center or science museum sitting in a sunlit area unlabeled and probably walked
right past it thinking “well that’s weird”.
That is just what happened to me for almost a whole year. I worked at
the Museum of Science, in Boston, MA, in the greenhouse exhibit and as I
watered the plants would walk past these two large plastic tubes with white
caps. They made great plant stands, but
they bugged me. I had seen things just like this on other museums in the United
States, France, and Germany with no labels explaining what they were. So, on a slow day I asked my boss Bob what
they were. “Oh, they are old Winogradsky columns.” he replied.
Curious I searched books in the library and the internet
trying to find out more about them. I found out the different colors, of
bacteria, and where they were in the column tell you about the bacteria’s
environment; is there oxygen, is there carbon, is there sulfur, and much more.
Each type of bacteria was a different color, so it would be easy to look at the
colors to pick out sulfur rich areas by looking for the red bacteria. Excited I
looked at ours. They were green from top to bottom. Where were all the other
colors I wondered? On Monday I peppered Bob with all my new information
and admitted I was confused because ours were all green. They need to be recharged he explained. Once
the bacteria have used up all the sulfur, oxygen, carbon and other compounds
all the other bacteria die and you are left with just the green bacteria. If I wanted to he would help me recharge them
only I had to get two dozen eggs from the cafeteria. Smiling I entered the kitchen explaining to
the chef I needed two dozen eggs for a science experiment and with much fear on
the chef’s part he handed over the eggs. Bob and I popped off the five foot
columns’ lids and started scooping mud into large buckets. As I was explaining to a group of visitors
what we were doing swish, plop, slash right into my mouth lands a huge clump of
foul smelling mud. Immediately the gag reflex kicks in as I try to spit out all
the mud, but I can still taste it. I run across the second floor as fast as I
can trying not to puke to the restroom.
A few minutes of dry heaving and a few gallons of water to rinse out my
mouth later I return to the exhibit. We
shred newspaper, crush up eggs and stir it into our mud buckets before dumping
it back into the columns topping them off with pond water.
A few days later we had all sorts of colonies of bacteria
red, purplish, rust colored, black, darker green, and white. Pockets of red
where there was more egg (sulfur) than other areas. A black layer formed near
the bottom where the bacteria which thrive with no oxygen lived. Three shades
of green some of which used oxygen, found near the top of the column and the
ones that didn’t use oxygen in the middle of the column. As the months went by the colonies changed
the black layer grew as the mud settled and the trapped pockets of air got
forced to the surface. Slowly the red disappeared as the eggs were eaten up by
the sulfur loving bacteria.
So, if you happen to see a Winogradsky column in a museum
look to see what colors you can find and if it is all green nudge then and tell
them to recharge their mud for the sake of Sergei.
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