Welcome to the Winobloggers webpage! Students and professors from different universities meet to discuss their findings on Winogradsky columns they constructed!
We learn how to formulate hypotheses, observe, comment, ask and reply to questions related to our scientific experiments.
Καλωσορίσατε στη σελίδα των Winobloggers! Διαδικτυακός τόπος συνάντησης φοιτητών, φοιτητριών και διδασκόντων δύο Τμημάτων από την Ελλάδα: Tμήμα Βιολογικών Εφαρμογών και Τεχνολογιών, Παν/μιο Ιωαννίνων και Τμήμα Γεωπονίας, Ιχθυολογίας και Υδάτινου Περιβάλλοντος, Παν/μιο Θεσσαλίας και ενός από την Ισπανία: Σχολή Θετικών Επιστημών, Πανεπιστήμιο του Cadiz. Παρακολουθούμε, σχολιάζουμε, ρωτάμε, απαντάμε σχετικά με τα πειράματά μας, τις στήλες Winogradsky!
Bienvenidos a la pagina web de los Winobloggers! Aquí los estudiantes y profesores de dos departamentos griegos, el Departamento de Aplicaciones y Tecnologías Biológicas de la Universidad de Ioannina y el Departmento de Agricultura,Ictiologíay Sistemas Acuáticos de la Universidad de Thessalia, junto con los estudiantes de Microbiología de la Facultad de Ciencias en la Universidad de Cádiz, se reúnen para observar, comentar, preguntar y responder a preguntas relacionadas con nuestro experimento, la columna Winogradsky.
'In the field of observation, chance only favors the prepared mind' Pasteur 1854
Monday, 12 December 2016
UNIVERSITY OF IOANNINA GREECE
BIOLOGICAL APLICATIONS AND TECHNOLOGY
– exposed columnControl
Between the 6th
and 7th week, we couldn’t descry any obvious difference.
The growth of the purple sulfur bacteria in the middle zone is still more
visible in the control column than in the warmth-exposed column.During photosynthesis, unlike cyanobacteria or plants, they bind sulfur
from the bottom of the column producing hydrogen sulfide, rather than oxygen.
Thus, the purple sulfur bacteria cause anoxic conditions in the middle zone
In both columns,
is still observed the presence of biofilms, the concentration of which, is
greater in the first column.
gradual distinction in the zones of the column, starting with the display of
sulphates purple bacteria, has only been observed in the control column, even
after 7 weeks. Thus, it can be assumed that the growth rate of the bacteria in
the 2nd column, is considerably slower, as zoning hasn’t been
observed yet. This fact is probably due to the rapid fluctuation of temperature.
In the warmth-exposed column, this affects the bacteria directly by limiting
the growth of the non-resistant ones at high temperatures. Also, the bacteria
in this column, in order to get protected from the temperature fluctuation,
could form spores, which means a static metabolic condition. Rather than that, the
overheating of the plastic bottle can excrete damaging chemicals for the
Hypothesis: The rapid fluctuation of the temperature on daily basis, reduces the
growth rate of the microorganisms in the 2nd Winogradsky column
UNIVERSITY OF IOANNINA GREECE BIOLOGICAL APLICATIONS AND TECHNOLOGY
Team 7: Serasidis Konstantinos, Tsinoglou Makrina Week: 4
Fourth week’s observation: 18/11/2016
previous weeks and this week’s observations several changes have been noticed
in the Control column. Firstly, at the bottom of the column green color has
been noticed. Specifically, these changes state the growth of green sulfur
bacteria. These bacteria require anaerobic conditions, sulfide ions and light
effect in order to photosynthesize. Also, at the bottom of the column are
noticeable black spots that are caused by anaerobic sulfur-reducing bacteria. These
bacteria use either sulfate or oxidized forms of sulfur as the terminal
electron acceptor, generating large amounts of H2S. The H2S
will react with any iron in the sediment, producing black ferrous sulfide. At a
higher level of the column a brown color in the sediment shows the growth of
heterotrophic bacteria. There is a green color band immediately above the
sediment. The green colored band is caused by the diffusion of H2S
from the sediment into the water column that enables anaerobic photosynthetic
bacteria to grow. The orange color in the water of the column that is caused of
purple non-sulfur bacteria seems to be the same as the previous week. Finally,
biofilm is observed at the top of the water column. A biofilm is any group of
microorganisms in which cells stick to each other and often these cells adhere
to a surface.
bottom of the column in the dark, the sediment is observed darker in comparison
with the previous week. The darker color of the sediment indicates the increasing
growth of anaerobic bacteria. Also, black spots are noticed at the lower levels
of the sediment that are caused by anaerobic sulfur-reducing bacteria. Additionally,
the black band which formed at the upper levels of the sediment is caused by
the growth anaerobic sulfur-reducing bacteria. The anaerobic conditions are formed
by the diffusion of H2S from the sediment into the water column. Finally, biofilm is observed at the top of the water column.
STUDENTS:NENA KOUKOUGELI DIMITRA-IOLI SKOUROLIAKOU UNIVERSITY OF IOANNINA GREECE BIOLOGICAL APLICATIONS AND TECHNOLOGY AQUATIC MICROORGANISMS
The differences between the two columns are more obvious from the 5th to the 6th week. In the first column, growth of urple sulfur bacteria in the middle zone is more odvious. Purple sulfur bacteria are group of proteobacteria capable of photosynthesis and they are illuminated in anoxic zones. Unlike cyanobacteria or plants they do not use water as ther reducing agent, so they do not produce oxygen. Instead, they use hydrogen sulfide from the botom of the bottle which oxidised ti produse granule of elemental sulfure In both columns, is still observed the presence of biofilms, the concentration of which, is greater in the first column After 6 weeks, it has started a gradual distinction in the zones of the column, starting with the disply of sulphates purple bacteria. Considering that the forementioned zoning hasn't been yet observed in the 2nd column we can safely assume that it's groth rate is considerably slower. This happens probably due to the rapid fluctuation of temperature that affects the bacteria, not only directly by limiting the growth of the non-resistant, at high temperatures, bacteria, but also it affects them indirectly by the overheating of the plastic bottle that excretes damaging chamicals. Hypothesis: The rapid fluctuation of the temperature on daily basis, reduces the growth rate of the microorganisms in the 2nd Winogradsky column