We began the Winogradsky column with some very simple steps. We retrieved a large soil and water sample from Big Walnut Creek, just behind the Waste Treatment Plant. We then added to it 17.35 grams of calcium sulfate, 17.92 grams of calcium carbonate, 7.89 grams of sodium sulfide, and four grams of shredded filter paper, and stirred the concoction thoroughly. After that, we split the mud and water into two sections, each into separate two liter graduated cylinders, and put a plastic sandwich bag over the top of each column, secured by a rubber band. In each column there were approximately 600mL of mud, and the rest was water. Then, we put one column under a 75 watt artificial light at the desktop. The other column, we merely set on the lab table, and the only light it got was from the ceiling lights during the day. The column under the incandescent light of the lamp grew very well. The layers of growth were very evident after some time. Just above the mud line there was a dense mat of filamentous organism, presumably cyanobacteria. This and the top of the mud probably constituted the aerobic and facultative aerobic (microaerophilic) zones of growth. Under this was presumably mostly the anaerobic zone (facultative to obligate). At first, the only growth was under the light, and mostly at the top.

That is because the aerobic, which like oxygen and sunlight had both of its components for growth. The anaerobic zone took a little more time, since it enjoys sulfur, and infrared light. Therefore, once anaerobic microorganisms had time to grow they began to increase. Since there is only so many nutrients and water to go around, when one zone grows, another falls a little bit. That is in fact what we saw happen. Once the anaerobic zone organisms began to grow, there was probably some interaction at the point of intersection between the two zones. The microorganisms were more or less fighting for domination, and at first the aerobic zone microorganisms suffered, after once dominating. However, after a while, the two zones began to coexist, and all of the different colors were thriving and prevalent, pretty much at a comfort zone. The white, sulfur-oxidizing bacteria marked the boundary between the aerobic and anaerobic zones. The properties of the column changed by these interactions by the increase of the anaerobic zone, and the decrease in the aerobic zone, after the near takeover of the aerobic zone. Then, after a while, there wasn’t a whole lot of change.

The column under no light except for the room was a different story. For a good while it appeared to have no growth whatsoever. After some time, though, we finally began to see some changes. There were some lighter green areas, and some white areas of aerobic growth, probably cyanobacteria and sulfur-oxidizing bacteria. There really wasn’t any evidence of anaerobic growth, and even the aerobic growth was on a limited scale. Obviously, this was mostly due to lack of light. Really, the majority of growth in the lighted column occurred directly under the light. The growth in this column was more than likely due to the periodic lighting of the room. While it is true that the anaerobic microorganisms don’t use visible light, they still need infrared light to filter down through the mud. There just wasn’t enough time for this to happen on a broad scale. There of course wasn’t any interaction between zones, either.

The growth of all microorganisms in both columns were facilitated by a number of things. First of all, the amount of light and water they were exposed to. The sandwich bag was put over the top for this reason, to keep the water from evaporating quickly. Then, the nutrients added were very important for the growth. The calcium carbonate, calcium sulfate, and cellulose (filter paper) were all sources of carbon for the microorganisms. This is a big part of their diet. The sodium sulfide is also food, containing sulfur, which is key for the organisms.

The physical and biological changes over time were plentiful and diverse. They are also connected. As more and more physical changes are spotted, this is the indication that diversity is increasing and biological changes are occurring early and often.

We attained the mud and water on September third. It was quite a nice day, about 73 degrees. The mud and water sat overnight, and on the fourth, we set up the columns. The column under the light exploded in the first week. We saw the mud settle, and the water get clear first, and almost immediately the column took off. The first colors that began to appear were the green, brown, and red. They were directly under the light, and closer to the waterline. As growth began to spread downwards, more spots began to appear. By the time the first week was over, there was one huge swath of growth, directly under the light. The part of the column not under the light was still unaffected, and had no visible signs of growth. It looked exactly the same as when we had first begun. The part under the light, though, was great. This was about a 9cm by 15cm section of great variety. This section began getting bigger and bigger during the second week. More colors began appearing as well, including black and orange growth in the middle of the mud. By the end of the second week, the swath of growth under the light had grown to 12cm by 18cm. The green and red colors remained, and even got more plentiful. The side without the light remained unchanged however. During the third week, the black growths especially began to increase in size. All of the growths remained and got more plentiful as well. The column was full of wondrous physical changes. However the swath under the light was maximized by the end of the week, and stayed about the same size for the rest of the time, at about 14cm by 20cm. Also at the end of week three, the original black growths had been replaced by orange, but new black growths were springing up and enlarging. During the fourth week, there wasn’t much change besides the usual. All growths were enlarging and the variety of colors was still intact. The side not receiving the light, though, was still unchanged for the most part. The fifth week finally saw some different changes. Finally, growths were spotted in the area of no light. There were some white, and black growths near the bottom of the mud. The light part of the column stayed pretty much the same. The growths kept their size and color. During the sixth and seventh weeks, the colors remained about the same, but small changes were being detected. The sixth week saw mud and bacteria begin to migrate up the tube. This caused the water to be rather cloudy by the end of the week. During the seventh week, we began to see tiny, filamentous bacteria springing up just above the mudline. By the end of the week there was a dense mat of spider web-like, filamentous bacteria that was very interesting and complex. As the eighth week through the end of the project progressed, we did see more changes, but on the same scale as before. The colors, red black, brown green, orange, remained and increased, along with the filamentous bacteria on the mudline. The water remained cloudy and the column looked interesting under the light. The part with no light remained fairly similar, as well. It had small white and black growths, but nothing significant. All in all the light column was the most interesting and gave us much food for thought.

The column under just the room lights during the day was much less interesting. Once the mud settled in the first week, no growth was observed for close to a month. In fact really nothing happened in the entire column, and it was nearly identical to the part of the light column not directly under the artificial light. By the fifth week, almost exactly when the no-light portion of the light column did, the no-light column finally began to show small signs of growth. There were small cream and white colored spots and these stayed close to the same for about another month, although they increased in size a little bit. Then, around the eighth week, the column began to differ a bit from its counterpart in the light column. We began to observe lighter green growth near the top of the mudline. This area began to increase in size at a slow but steady rate. By the end of our observations it had included a circular section of mud about 3cm deep. This was a small, but obvious are of growth, and was by far the largest area of growth in the column for the entire time.

Obviously, the light and dark columns were extremely different. This was evidenced by our observations of growth and also by the fact that only two of our seven final isolates came from the dark column. This does not mean that there were more microorganisms in one column of the other. It just means that the column in light showed more physical changes over time, translating into more diverse biological changes. The light column therefore developed into a more visible, complex ecosystem. The more observable growth also biased our decision to try and isolate more bacteria from the light column. The final list of isolated bacteria, while only down to a choice of several genera in some cases, is as follows, and is rather diverse, showing a wide range of physical and biological characteristics, as it should.

#1—Lactobacillus

#2—Neisseria Macacae

#3—Azomonas Agilis, A. Insignius, A. Macrocytogenes or Neisseria gonorrhoeae

#4—Azomonas, Azotobacter, Pseudomonassyringae or P. viridiflava

#5—Brachybacterium, Caryophanen, Rothia

#6—Brachybacterium, Propionibacter, Rothia

#7—Escherichia Coli