Winogradsky Column
Please be sure to read through this entire document BEFORE FRIDAY so that you are aware of what is
expected.
Background Information
Bacteria and Archaea are not only the most ancient forms of life, going back at least 3.5 billion years, but
they are also the most diverse and numerous organisms on Earth. For the first 2 billion years of Earth’s
history, they were the only living things on the planet. These microorganisms exhibit astounding diversity
in metabolic mechanisms, such as oxygenic and anoxygenic photoautotrophy, chemoautotrophy, and
photoheterotrophy, to name a few. They also play an essential role in cycling elements that make the
planet habitable for all other types of organisms. The diversity of these simple life forms is evident in the
myriad of ecological niches they inhabit, from hydrothermal vents to the acidic lining of your stomach.
In this activity, you will observe a sampling of the diverse microorganisms that live in your local
environment. You will set up Winogradsky columns—simple devices for constructing a stratified
ecosystem—that illustrate different types of microbial metabolism in a colorful way.
Materials that must be provided by you on the day we construct our columns (FRIDAY)
If you do not have these materials, then you cannot construct your Winogradsky column and will
lose 10 points of the total 50 points for this assignment. Also, you will be responsible for
constructing your columns on your own time then placing them in the proper location in the room.
 2 clear, 16-ounce plastic bottles
 3-5 cups of sediment (mud)
 Water from the same area where the mud was collected
 Optional: Digital camera for pictures of your bottles. You can use your camera phones as well if
you have a way to print the pictures.
Collecting the Sediment Sample
1. Bring a container (that is big enough to hold 3-5 cups of sediment plus additional water) with a lid, a
shovel (or anything to scoop with), and a camera (digital or phone).
2. Identify a sediment source in your area. Anywhere with dirt and water is appropriate, such as a stream,
creek, marsh, pond, bay, ocean beach (sand), or even a backyard puddle.
3. Take 2 or 3 photographs of your sample site to illustrate the location where your sediment was
collected. Each group member will need a copy of these pictures for their observation journal.
4. Collect approximately 3-5 cups of sediment in the container. The sample should be wet. Avoid or pick
out rocks, sticks, and leaves.
5. Scoop several cups of additional water from the sample site into the container.
How to Assemble the Winogradsky Column:
1. Read all the instructions before starting the lab. Ask Mr. Reid if you have any questions.
Remember, you are using materials that may be dangerous to your health.
2. Collect the necessary materials. The materials are:
a. Provided by me:
i. 2 Labels (Post-its will work) to mark the following on each container: Group
name and either “control” or “carbon and sulfur”
ii. Beaker for measuring sediment and mixture
iii. 2 plastic gallon baggies for mixing sediment
iv. A carbon source, shredded newspaper; approximately 1 cup loosely packed
v. A sulfur source; raw egg yolk is best
vi. Funnels
vii. Sharpie
viii. Large spoon
b. Provided by you:
i. 2 clear, 16-ounce plastic bottles
ii. 3-5 cups of sediment (mud)
iii. Water from the same area where the mud was collected
iv. Optional: Digital camera for pictures of your bottles. You can use your camera
phones as well if you have a way to print the pictures.
3. Write “control” on one label sticker and “carbon and sulfur” on the other.
4. Stick the labels on the sides of the 2 16-oz. plastic bottles near the bottom.
5. Label one plastic baggie as “control” and “carbon and sulfur” on the other.
6. Add approximately 1.5 cups of the sediment sample that you collected to each of the plastic
baggies. Make sure to remove any large debris such as leaves, rocks, or sticks.
7. For the control baggie, skip to step 9.
8. For the “carbon and sulfur” baggie, add ½ cup of shredded newspaper (loosely packed). The
newspaper contains cellulose, a source of carbon. Then add the yolk of an egg to the sediment as
well. The egg is a source of sulfur.
9. Mix each of the baggies thoroughly. Slowly mix in the water you have brought from your
collection site until the mixture has the consistency of a milk shake. If there are any sticks or
large pieces of debris left, remove those.
10. Using a large spoon, slowly add approximately 1 cup of the mixture to the appropriately labeled
plastic column (bottle) using a funnel. As you add the sample, tap the column on a counter or
table to release any trapped air in the column. The sediment should fill ½ to ¾ of the column.
11. Add water from the sediment collection source on top of the sediment until there is a 2-cm
(approximately an inch) layer of water on the surface. (There should be air at the top of the
column.)
12. Place the lid on each column and turn the lid a ½ turn. DO NOT tighten the lid!
13. Place both containers in a well-lit space such as a windowsill with the label facing AWAY from
the window.
14. Using a camera or phone, take a photograph of the columns to document week 0 of the
experiment to be printed and placed in your observation journal later. Alternatively, you can draw
a detailed model of your column.
Winogradsky Column: Observation Journal – 50 homework points
Weekly Observations
You should observe your Winogradsky columns for approximately 8 weeks. Spend a few minutes each
week recording your visual observations of the columns in your lab notebook. Make your observations
weekly at the start of class each Friday. If you are absent Friday, you will be responsible for making your
observations BEFORE OR AFTER class on Monday. When taking photos of your bottles, take photos of
them side by side with the labels showing so it is obvious which bottle is which. If you move the columns
to take the picture, be sure to put them back in the same location facing in the same direction.
These are the criteria you will be graded on:
 Completion (are all entries present)
 Criteria followed (are all required components present?)
 Organization (is your data neat and easily understood by all readers)
 Detail of observations made (are your observations in depth and easy to understand?)
 Analysis of observations based on analysis questions (are you analyzing your data as thoroughly
as possible?)
 Writing (are you using grammatically-correct, complete sentences?)
 Pictures of area where sediment was collected (must be actual picture)
 Pictures of bottles (by camera [must be printed in color] or drawn)
Journal Instructions
1. Number your pages. Furthermore, keep all the journal pages next to one another. You will need
to designate a section at the start or end of your lab notebook.
2. You will need 2-3 printed pictures of the location where the soil/water was collected on the first
page.
3. State the exact time and date when each observation was performed.
4. Take a picture OR draw a diagram of your column EVERY OTHER time you make an
observation (so week 0, 2, 4, 6, 8). Use colored pencils or markers to show the different colors
visible in your column if you are drawing. Be very specific. I will permit digital cameras (or your
cell phone) for taking pictures if you’re so inclined to print them out and neatly attach them into
your journal. Printed pictures MUST be in color so that the changes occurring in the bottle are
actually visible.
5. Examples of observations that can be made.
a. Has the color of the sediment changed? If so, note the color(s).
i. When different colors appear that didn’t exist before, these are bacterial colonies
forming.
ii. Based on that information, estimate how many different species of bacteria are
present.
b. Has the color of the water changed? If so, note the color(s).
c. What differences between the columns do you observe?
d. Does the sediment appear to have settled? Shifted?
e. Do you see any layers forming in the sediment? In the water?
f. How does the thickness of the layers change from week to week?
g. Are there differences between the side facing the light and the side away from the light?
h. Describe any other changes that you may see in your column.
6. Use the last page of your journal to complete the analysis questions provided on the next page.
Example Journal Outline
Time: 11 a.m.
Date: Wednesday, August 20, 2010
Diagram:
Page Number: 1
Describe
Soil colors:
Smell or odor:
Number of layers forming:
Thickness of layers:
Water color:
Estimated number of different bacterial colonies:
Other observations:
Analysis Questions (These should be the last page of your observation journal):
During the course of the experiment, spend some time considering the following questions. Some of these
questions may require extra research (e.g., to learn about the sulfur cycle).
1. How do your columns differ? How are they the same? Explain the differences you see.
2. Did you observe changes in the control column? If so, explain why they occurred.
3. Winogradsky columns form oxygen concentration gradients. Predict the distribution of oxygen
throughout the column. (Consider the entire column: the sediment, the water, and the air.)
4. Winogradsky columns form sulfide concentration gradients as well. In the column that contain
egg yolk, predict how sulfide will be distributed throughout the column. (Consider the entire
column: the sediment, the water, and the air.)
5. Sulfur reduction is a form of anaerobic respiration. Desulfovibrio are an example of bacteria that
reduce sulfur as a way of respiring in the absence of oxygen and release sulfide. Where in the
columns would you expect to find them?
6. Purple sulfur bacteria and green sulfur bacteria are two types of bacteria that use sulfide to
support photosynthesis. In general, green sulfur bacteria tolerate higher levels of sulfide than
purple sulfur bacteria do. Predict where the green and purple sulfur bacteria would be in relation
to each other. Also predict where in the column the purple sulfur bacteria would be in relation to
the Desulfovibrio bacteria.
7. If samples were extracted from the various layers of all the columns, where would you find
photosynthetic organisms such as cyanobacteria and algae? Explain why.
8. Explain how Winogradsky columns illustrate the diversity of microorganisms found on Earth
today in terms of the diversity of niches they occupy.
9. Explain what the Winogradsky columns illustrate about life on early Earth.