Final Winogradsky Column Update

DAY SEVENTY-NINE

After 79 days of growth I have observed significant changes in both columns and the amended and control columns are strikingly different from one another. Both columns were exposed to the same amount of sunlight and have been kept outside for weeks because of the strong odor coming from the columns, especially the amended column. I don't have access to a microscope so I can't be certain which microbes are present in my columns, but based on the patterns I see in the columns and applying what I know about different groups of microbes and their growth requirements, I can make a prediction about what types of organisms are present. I also referred to our textbook as well as a website on Winogradsky Columns in order to more accurately identify the microbes in my columns (http://www.woodrow.org/teachers/bi/2000/Winogradsky_Column/winogradsky_column.html).

Observations of the control column (just lake mud and water):
-the water layer is still very green and is populated by a lot of algae and plant growth
-there are a few places with a film floating on the top of the water but mostly the top is open water
-the water and mud level have stayed fairly constant
-the top half of the mud layer looks mostly unchanged
-the bottom half of the mud layer is very orange/rust-colored and near the bottom are orange clumps about the size of a match head
-the mud still has several air pockets throughout and some type of channels

Microbes possibly growing in the control column:
-much of the green color at the top of the column is likely photosynthetic cyanobacteria and there may be some diatoms and other organisms in the water
-the top light-colored layer of the mud is rich in oxygen so the bacteria there are probably aerobic sulfide oxidizing bacteria like Beggiatoa, Thiobacillus, and Thiothrix
-below that oxygen-rich layer is an oxygen-scarce layer (the microaerophillic zone) and this is the rust-colored area meaning it's likely populated with purple nonsulfur bacteria like Rhodospirilium and Rhodopseudomonas
-below that should be the anaerobic zone, but it is difficult to see because I didn't detect any evidence of anaerobes like Chromatium or Chlorobium
-the characteristic red, green, and purple layers seem to be absent from my column, perhaps because this column is lacking an added sulfur and carbon source


Observations of the amended column (lake mud, oatmeal, and water):
-one of the most striking differences between the two columns was how the level in the amended column dropped during the last few weeks (the water and mud levels were originally level with one another and now the mud in the amended column has compacted down)
-the water layer in the amended column went from being fairly clear, to gray and cloudy, to a milky orange color, and now it's dark gray with a hint of purple
-there is a distinct rust-colored ring on the top of the water layer but some of the water evaporated so the water level is now slightly below the ring
-there is a significant biofilm on the top of this column; it's intact and stretches across the top of the water and it appears scaly and somewhat iridescent
-the odor has only become stronger with time
-the white spots throughout the mud where the oatmeal pieces are have expanded and now it appears as though there is light-colored growth in those spots

Microbes possibly growing in the amended column:
-it's interesting that there is and never has been any green growth in this column so the evidence of cyanobacteria is basically nonexistent
-I'm guessing that it was photoheterotrophs (same as in the control column) that created the rust-colored line and with the drop in the mud and water levels it's now above the water
-other colors are absent from the column; the rest of the mud is simply very dark-colored with patches of white
-the dark mud is mostly anaerobic and is likely populated with Desulfovibrio and the methanogens may be the reason for so much odor coming from this column

Overall it was really neat seeing the progression of organisms in both columns. I was shocked to see how different they are and was surprised to see more colors in the control column; several of my predictions were very different from what I actually observed.

Winogradsky Column Update #3

DAY THIRTY-NINE
About two weeks ago I had to set the columns outside. The control column wasn't giving off much odor but the amended column with the oatmeal had a very strong odor emanating from it. It wasn't strictly a sulfur smell, but it smelled foul and somewhat like decomposing organic matter.

The temperature outside has been variable - the nights get close to freezing but lately it has been very sunny and the temperatures have been around 60 degrees F.

Some of the water from the amended column has evaporated and the thin layer of orange bubbles/scum clinging to the bottle has become has become more pronounced. The water at the top has become cloudier and there appears to be a lower, more orange layer within the water layer. The soil in the amended column is very dark, almost black in some spots, but there aren't any other color changes.

In the control column there is still a large amount of plant growth in the water layer and the water is still quite clear, but with a green tint. The middle 1/3 of the soil has taken on a rust-colored tint with the rest of the soil appearance unchanged.

Winogradsky Column Update #2

DAY NINETEEN:
I'm noticing a variety of changes in both columns but not any significant color changes yet. There is definitely an obvious difference between the control column and the amended column and I haven't observed much evidence of microbial activity in the control column. The gas production of the amended column seems to be under control now, at least it's not overflowing anymore, and both columns have kept their water at approximately the same level as when I pulled water off on day five. The columns are still receiving indirect sunlight although we've had sunnier days lately and the sun's ray may be more intense than they were at the beginning of the experiment.

Observations of the control column (just lake mud and water):
-there is a lot of plant growth, the plants have grown tall quite quickly
-the water went from being really clear to having a green tint
-very rarely does a bubble rise to the surface
-there doesn't seem to be any odors emanating from the column
-there aren't any major changes in the soil's appearance and the surface of the soil is still quite flat
-there isn't an oily substance on the surface

Observations of the amended column (lake mud, oatmeal, and water):
- the water at the top of the column is very cloudy, like skim milk with a little dirty water in it
- there is a very strong odor coming from the bottle, not a sulfur smell, just really foul smelling
-the soil has large holes in it and the boundary between the soil and the water has become very uneven, there are big valleys in the soil level
-there is a lot of gas production; large bubbles float to the surface frequently
-there is an oily substance floating on the surface of the water
-the plastic film on top looks like a petri plate; lots of little light spots
-there are a couple of white floaters on the surface of the water, half the size of a pencil eraser but it's difficult to see what they are through the film
-just above the water line there is a line of orangish-brown growth and a black line has started just below it
-the soil just below the water line is darker than the rest and has a thin section of nearly black soil going through it
-this column also appears to be attracting small animals: I found a tiny red and black insect walking laps around the circumference of the plastic film and it kept doing it for nearly an hour and there was also a tiny spider that got inside and died in the water (my guess would be that the pungent odor attracted them)



I'm anxious to see what it will look like in another week or two!

Winogradsky Column Update

DAY FIVE:

I was out of town for two days and when I returned, my amended column had lost a little of its water. There were trapped gas pockets in the mud so the mud level had risen and forced a little water to go up and over the edge of the bottle! The plastic wrap was also bulging a bit with trapped gas caught inside the bottle. So I undid both columns and took a bit of water off the top and also released some of the gas trapped in the mud of the amended column. It's interesting that the columns already looks so different. The control column without any oatmeal has hardly changed: the water is clear and I haven't observed any changes in the mud. The amended column with the oatmeal, however, has cloudy water, a lot of gas in the mud, it bubbles occasionally, and the sulfur smell was much stronger than with the other column. I never expected to see changes and differences so soon!

Winogradsky Column Setup

DAY ONE:

Introduction:

I decided to make two columns for this project, a control column and an amended column. I was very interested to see how a simple column with just mud and water would look because several resources mentioned how well the columns turn out if you don't add anything to them. I was also interested in seeing what effect adding just one thing would have so I didn't use a sulfur source at all. My first column is simply mud and water from the lake I live next to and my second column is exactly the same except I added a oatmeal as a carbon source. I used a combination of protocols from two sources: http://www.lyon.edu/webdata/users/dthomas/BIO100L/Winogradsky_column.pdf and http://www.personal.psu.edu/faculty/j/e/jel5/biofilms/winogradsky.html .
I'm curious to compare my two columns and also to compare them with the columns other people made to see if a simple column does encourage a significant amount of growth.

Materials:
~Bucket for collecting the mud
~Two 1.5 L clear, plastic soda bottles
~Mud collected from the lake shore
~Water collected from the same location~
~A long dowel
~Oatmeal (carbon source)
~Plastic wrap
~Rubber band
~Newspaper

Procedures:
I collected an adequate amount of mud and water from the lake shore, removing as many twigs and stones as I could. Then I laid out newspaper on my work surface and cut the tops off the soda bottles. I then filled one bottle (control) 3/4 full, using the dowel and tapping the bottle to remove any air bubbles. Once it was 3/4 full I topped it off with lake water and then covered the top with plastic wrap and a rubber band. To the second column (amended) I followed the same procedures except that I added oatmeal to the mud before I put it in the bottle. I then set both bottles under a window that does not receive any direct sunlight. I photographed the columns after I set them up and will check on them periodically over the next few months to observe any changes.

Predictions:

By the end of the growth period, I predict that:

-There will be more growth in the amended column (the column with the oatmeal) than the control column

-Aerobic phototrophs will be numerous near the top of the columns where they can access oxygen and more light

-Microbes that are anoxygenic will be more numerous near the bottom of the columns

-Photosynthetic bacteria will be more concentrated on the side of the columns facing the window