Day 45.  UCA. Rio San Pedro sedimentWinogradsky columns C2 and C3.

Today, 5th of June many different types of mycroorganisms can be seen inside the columns. Those mycroorganism has been living and multiplying since March in two different life conditions:

-In an illuminated environment, we can see many dark stains with a colour between blue and grey in the bottom of the column. Those stains are formed by anaerobic bacteria that breathe with H2S.
In the middle of the column, an orange stain can be seen. This stain is formed by Rhodospirillum, photohertroorganotrophic organisms.
Finally on the surface of the column we can see many green stains, that are cianobacteria and algae.

- In a dark environment, we can see in almost all the column a really big stain with a dark colour between grey and blue. This stain is formed by anaerobic bacteria that breathe with H2S bacteria. On this stain, we can see some orange stains, that are formed by Rhodospirillum, photohertroorganotrophic organisms bacteria.

According with those results, we can declare that in those different life conditions, we can see the same type of mycrooorganisms in both colums, except, that we cannot see photoautotrophic mycroorganism in the dark enviroment, because those mycroorganisms need light energy to live.

Light environment

Dark environment

Winogradsky Column. Day 45. UCA B1-B2

After almost 50 days since the last time we checked the columns we can see several changes in their composition.

We´ll be talking about the column B1 because the other column got lost at some point along these days.

as we can appreciate, the changes are noticiables:

• there are plenty of places with orange coloration (due to photoheterotrophic microorganism)
• darker areas mainly at the bottom part (because of the action of sulfate anaerobic breathers)
• olive green zones due to anoxigenic microorganism.

UCA_4B_3B_day85

UCA_4B_3B_day85  

San Pedro's River sediment + 0.3 g paper + 0.1 g CaSO4

Group 3B: Alvaro Lucero Garófano and José Luis Hernández Fernández.

Group 4B: Paula Gilabert Prieto and Pilar Grosso Rodríguez.

We have bad news for you, today is our last post.... :(

Our column has been changing during these days since the last time we saw them and we posted it.

The changes produced are:

Column in contact with light:

We can appreciate a change of color from brown to orange. That color manifestate the appearance of the bacteria Rhodospirillum which is photosynthetic

On the other side, we can see some green spots which we think they are algae. Also in this part we can appreciate some black spots at the bottom, which means that are anaerobic organisms.

Column without light contact: 

The only change that we can see, is that the difference bettween anaerobic and aerobic is more defined.

UCA_7B,8B_1: Day 44

Winogradsky column- Day 44

Group 7B (Lucas Garín Ortega and Alba Mejías Gallardo)

Group 8B (Laura Lucena del Amo and Noelia Moares Fernández)

After 44 days, we have checked our columns and we have observed a few changes.

The column made by group 8B, the one exposed to sunlight, didn't have a lot of changes. We could see that the layer of  lighter color previously seen was bigger than before, that means that there were more photoautrophic microorganisms. Also, we could appreciate that there were more bubbles, formed by the sugar fermentation of microorganisms chemoheterotrophs.

Group 8B column

The column made by group 7B, the one kept in the dark, has suffered the following changes. We could appreciate that the column was darker due to the H2S breathing of bacteria. The water on the surface has cleared and an orange layer has formed on the surface. This could be because of the proliferation of photoorganoheterotroph microorganisms. Last but not least, a lighter spot has been formed from a bubble generated by microorganisms breathing.

Group 7B column

UCA_C3-C4_day44

A few weeks after the preparation of the column, we observed both of them, and we noticed some changes.

The C3 group’s column presents the following characteristics:

• The orange spots are photoheterotrophic microorganisms, which use as power source the solar energy, and reduced iron.
• At the surface, we could find green algae and cyanobacteria, since they need oxygen to perform the cellular respiration and sunlight to make the photosynthesis.
• Along the column, we could find tiny white spots, which can be elementary sulfate.
• We could also see small bubbles, which can be due to the fermentation of the chemoheterotrophic micoorganisms.
• We can appreaciate along the column some black spots, which are more intense at the bottom of it. They are due to the anaerobic microorganisms, being stronger as the oxygen gradient decreases.

The C4 group’s column differs from the C3’s in the following characteristics. The rest of the microorganisms are the same as the other one.

• We can find along the coloumn oxidizing bacteria.
• The photoheterotrophic microorganisms of the column use as carbon source the cellulose of paper, and as power source the sunlight.
• It doesn’t present white spots since it didn’t contain sulfate.
• The orange spots are bigger, because of the cellulose that the paper provided.

UCA_A1, A2: Day 44

In our Winogradsky Column we can see a lot of colours that correspond to very different kind of microrganisms. On the top we can see a big green stripe, that corresponds to algas and heterotrophic bacteria. Under this stripe there is a little orange bubble and we suppose that corresponds to an iron oxidizing bacteria. Under that we can see  amounts of scattered red purple colour, a part localized just under this bubble and another part almost in the bottom of the column. The part wich is localized just under the bubble corresponds to non-sulfure bacteria and the other part corresponds to sulfure bacteria.

Alga obtains energy and carbon by doing photosyntesis  using the light energy and the water. Iron oxidizing bacterias use Fe²⁺ and CO₂.  Non-sulfure bacterias use organic carbon and light energy. Sulfure bacterias use H₂S, light energy and CO₂ that produced from the CaCO₃. The CaCO₃ and the water were introduced in the column and the iron can be contained in the mud. We also must remember that microorganisms that grow on the top have more oxygen and less sulfure and the microorganisms which are in the bottom have less oxygen and more sulfure.

UCA_5B, 6B_1: Day 44

44 days have passed since we last checked our Winogradsky columns. In the column without sugar we can observe that some black sediments have appeared. That indicates the presence of anaerobic microorganisms (as sulfate-reducing bacteria) which produce H₂S from CaSO₄ (that served its purpose as a sulfur source). This compound finally reacts with the iron present in the sediment of Rio San Pedro, producing FeS, known for its black color. What's more, there's still some water remaining in this column. 

As the columns were placed in the dark we can’t notice the presence of photosynthetic microorganisms in neither of them.

​On the other hand, in the column with sugar we observe that the same anaerobic microorganisms that appeared in the column without sugar have appeared in this one too. 

Furthermore, we can see that some type of fermentation has happened (due to the fact that the water we found in the previous column has been pushed out, likely because of an excessive emission of gasses, such as CO2), and we could in theory be able to determine its kind. In order to distinguish between lactic and alcoholic fermentation, we should have conducted some analytical experiments that we couldn't afford to do. Despite not knowing exactly what kind of fermentation it was, we can definitely confirm our hypothesis: if there are yeasts in Rio San Pedro (which has been proven to be right), in presence of sugar they'll undergo fermentative processes. 

Thus, we can conclude the experiment was successful and our hypothesis was accurate too.

We've already tested and confirmed our initial hypothesis, so for now on the columns will be placed in the light for further observations. We expect to find some photosynthetic microorganisms that may (or may not) benefit from the increased growth rate found in the column where we placed 4 g of sugar (no more, no less). Considering the enormous emissions of CO2 (coming from either fermentation or cellular respiration) in the sugar column, we believe this could help photosynthetic microorganisms proliferate, which capture and reduce CO2 in order to grow, as shown in the following animation.

Hence, we estimate a greater growth rate of photosynthetic organisms in the sugar column, compared to the control one (that has no sugar at all).

UCA_A4_A3_day45

Tube in darkness
We can see that there's air due to the fact that there was too much sustrat and microorganisms have produced CH4 .
In this column all is dark, it has anaerobic bacteriums.

Tube in light
We can see that in the surface, the tube has turned to light brown due to the presence of aerobic bacteriums.

When we compared both columns, we can see that only in the light column has appeared an extract light brown. Therefore, we deduce that the microorganisms that have grown there, are photosyntetic.

 Darkness                                                                                                           Light

UCA_4B_3B_day44

San Pedro's River sediment + 0.3 g paper + 0.1 g CaSO4

Group 3B: Alvaro Lucero Garófano and José Luis Hernández Fernández.

Group 4B: Paula Gilabert Prieto and Pilar Grosso Rodríguez.

Did you miss us? No problem, we are back again to show you the evolution of  ours Winogradsky's columns after 44 days 

We can appreciate several changes in both columns.

The column 3B, which was in contact with the light has developed different changes.

Firsly, all bacterias which has grown in the column are photosyntetic bacterias due to the fact that they are in contact with light. Then we can classify this bacterias in two groups.

Aerobic bacterias and anaerobic bacterias.

The aerobics bacterias are on the top of the column because all the oxygen of the column are on the top. 

Also we must emphasize that there are a gradient of oxygen in the column, and the more it descends in the column, the less oxygen are in it. The bacterias which are at the bottom maybe can use the sulphate as the last one who accepts electrons. So this is the reason why has grown bacterias in a different colour at the bottom.

The surface which has been in contact with light is lighter than those surface which has not been in contact with it. 

The column 4B, which was in the darkness has developed some changes.

First of all, we can see that  there are a gradrient of oxygen in the column again, so at the bottom has grown anaerboic bacterias.

the difference with the other column is that in this one has grown chemosyntetic organisms, so the colour of this column is darker than the other one. 

Finally, Ours firts ideas of what could happen, are being succesful with our result

3B

4B

 

UCA_5A_6A_7A: Day 44 Winogradsky column´s evolution after a month

Winogradsky column´s evolution after a month:

We are back again, and now, we are going to show the changes in our columns:

5A Winogradsky Column:

The group 5A let his Winogradsky column in an illuminated environment, and after one month, we can observe that there is a colour variation at the top of the test tube because it has acquired a red tonality in the liquid part. The solid part doesn't have colouring. It is quite reasonable, since we put a lot of N and S sources into the tube, therefore, there are a lot of anaerobic bacterias, which are responsible of the colour variation. Since the amount of anaerobic organisms is incredibly big, there aren't any kind of  aerobic organisms in our test tube.

6A Winogradsky Column:

The group 6A let his Winogradsky column in a dark environment, and after approximately 30 days, the column is a little bit darker. But it continues with a little brown part at the bottom, we think it's because there aren't too many nutrients, or it will be because in that zone has grown another variety of bacteria. Throughout the column we can observe various black points and it could be accumulations of bacteria.

7A Winogradsky Column:

The group 7A let his Winogradsky column in an illuminated environment. We have observed changes after a month. The side of the column, in which the light does not reach, has a grey colour produced by anaerobic bacterias. Also, the column has a red colour in the middle. We think it may be produced by aerobic bacterias, which produce a substance with this colour. Secondly, we noticed more bubbles produced with the CH4 that bacterias expel out. Finally, we conclude with a general development of aerobic and anaerobic bacterias through the column along this month, in a way that we expected.

6A Winogradsky Column

7A Winogradsky Column

5A Winogradsky Column