1zIUK2Y

THE INVISIBLE
BEAUTY OF
DIATOMS
Tiny diatoms create an external skeleton for their
dwelling and protection, a shell or frustule made
of silica. These creatures are incredibly diverse
and can strive in every water environment. More
than 10.000 different species have been identified
so far. Diatoms inhabit even the smallest
living spaces in rivers, lakes and seas; they live
free in the water as plankton algae or attached
to the plants, stones and pebbles. They can even
be found in solid manmade waste and in silt
sediments.
Diatoms form the start of many water food chains
and are extremely important producers of oxygen
on the Earth. Like all plants, they need daylight
for existence; so for them, the least pleasant and
the most stressful environment are muddy rivers
and lakes. Murky and muddy waters are linked
with inappropriate human attitude to the land
and water environment. Continuous erosion of
the river banks with no vegetation has distinctive
negative impacts to these water dwellers.
Diatoms are wondrous microscopic creatures
that are telling us about the ecological status of
water bodies and are the reflection of our attitude
towards the water and land environment. They
quickly respond to the changes in the environment
either with reduced abundance or, even
more alarmingly, with the disappearance of
specific species. Land use changes in the catchment
area, pollution of land, atmosphere, and
consequently water bodies, are reflected in the
community of diatoms.
Diatoms are also important historical witnesses
— an invaluable history book. They are telling us
about ecological status of water bodies thousands
and millions years ago, recently also about the
pollution and human attitude towards the natural
environment. Their marvellous skeletons are
silent witnesses of human environmental sins.
Analysis of sediments in Ljubljansko barje (Ljubljana
moors) and the remains of diatom shells
have proved that in this area, a huge shallow
Ljubljana lake was spread in the past, where pile
dwellers and beavers flourished.
Ljubljanica river, also named the “River with
seven names” is an urban aorta not adequately
appreciated today. It offers home for various
organisms, including many species of siliceous
algae — diatoms. A wonderful world of these
indicators of water environment is revealed
under the microscope, especially the scanning
electron microscope. Extraordinary micrographs
document diatoms in their full diversity and
splendour. Siliceous creations excite the imagination
of different artists, from architects to fashion
designers. Maybe the Riverman had known these
secret treasures of Ljubljanica and, with tiny flint
pearls, lured Urška into his secret home.
Researchers are constantly surprised by the
extraordinary form diversity of diatom frustules
which protect algae from impacts of the environment
and are specific for each species. External
skeleton is shaped similar to a beautifully ornamented
case in which grandmother’s pearls are
kept. However, diatoms themselves are the most
beautiful pearls of the nature! One only has to
observe them under a microscope or admire on
wonderful micrographs.
Diatoms confirm that the aquatic environment is
becoming unsuitable in many places due to selfish
human attitude towards the environment. The
power of capital often prevails over the sustainable
use of the environment and too many are still
convinced that the man is the lord of the Earth.
This is far from the truth. We are only the companions
of many other creatures on this planet
that are far less dependent on us than we are on
them. This has to become a part of our awareness
and humans must stop treating the Nature as
our property. We cannot simply exploit it to the
Izvir Pod stenami spomladi / The source Pod stenami in springtime
5