Cladocera презентация

The Cladocerans are an order of small crustaceans
What the Cladocerans are?
4 orders:
Cladocera (water flee);
Anostraca (fairy shrimps)
Notostraca (tadpole shrimps) ;
Conchostraca (clam shrimps) ;
Size <1mm.
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fig.1 – 4 phylogenetic orders and extinct branches
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Known from mid-Mesozoic era (~170 mln.y.ago);
First modern Cladocera – 150 mln.y.ago. (Jurassic period);
For the last 200 000 years no morphological changes have been observed.
Time range
fig.2 – meso-cenozoic time scale
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Where to collect samples from?
Major lakes habitats
Open water planctonic habitats
Littoral benthic habitats
Paleolimnological samples are usually being taken from the basin parts ;
The abundance of Cladocerance is the highest in the mid-latitudes at t=15-20C
Cladocerans eggs store its genetic material for centures ;
After death Cladocera breaks into thousands of fragments (usually several thousand per cm3).
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Climatic change – (water temperature) ;
Lake level changes and lake terrestrialization ;
Lake eutrophication ;
Acidification (pH level).
The use of Cladocera in tracking environmental change
Living subfossils: carapace (left) and claws (right)
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Cladocerans size as an indicator of water temperature and fish abundance ;
Cladocerans subfossils respond to trophic state ;
Melanin as an indicator of optical lake`s envinroment
Reconstruction methods
Freshwater cladocera
An individual cladocera
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