Three weeks later there are some remarkable changes: the different strata are now
more visible and we can start appreciating the first signs of life.
As we can see, there is a grey
layer in the bottom due to the accumulation of organic matter. The bacteria who
live in this stratum, Clostridum, consume cellulose and produce glucose by
fermentations, as the levels of oxygen are very low (almost unexisting).
There is also a reddish level
where we can find iron oxidazing bacteria. The oxygen concentrations are now
considerable.
We find plenty of black
precipitate in the low levels. This black precipitate is FeS produced by the
bacteria when they release H2.
We may also see, in contact with
the water, in the upper level, little seaweed (algae), as well as bubbles
produced by the bacteria living in this layer, that has become bigger and whose color is now close to brownish green.
No comments:
Post a Comment