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Year 2001 - White Stork Project
Schools from three Countries together
in Europe At School 2001 competition
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Published by School M.A.R, Croatia, I.E.S.J-Sera, Spain
and G.S.G Moisil, Romania.
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EkoMAR zine > art#001047
19.03.2001
S.O.S. THE DANUBE
S.O.S.-THE DANUBE
The Danube means for us fish and cereals trade,protection against the invasion of migratory populations who invied our land for its wealth and especially because of its strategic position between Orient and Occident.The clock of the History recorded on the Danube great restleness and also great changes.In 100 A.C. the Roman Emperor Trajanus finishes the road through Boilers.The 101 year saw the first works in order to regularize the Danube stream(because of the cataracts theriver was deviated for ensuring the navigation).The Iron Gates represented a difficult obstacle to pass through for the navigation.Later,this strengthof the river produced power.Even if many pages were written about the Danube,every generation’s conscience there is a place this pages occupy.I have in front of me the map of the Danube from 1934.I see a chain of pools, islands and aits and the holm near by the river.I also have in front of my eyes the present map of the river.I can see a strip with new constructions of merchant marine or not,dams, artificial pools.
About 30 years after 1934 the Danube changed its aspect at the Iron Gates, from natural running water ecosystem in artificial lake ecosystem.What did it mean for Danube ‘s life? Following just two aspects the ecological factors and the dynamics of the ichtyology-the picture is alarming.The both, upstream and downstream researches related to Iron Gates I and Iron Gates II as well as the research about the artificial pools put in front of us considerable changes in the ichtyofauna regarding its density,frequency,relative plenty and changes concerning the reproduction places or the period of migraton.At the level of the environmental factors transformations were pointed out too,by instance the quantity of the melted oxygen,the temperature,the suspensions and the quantity of organic substances.The dependance of the melted oxygen given the temperature produced modifications in the piscicultural fauna.Soon enough the species of andronical migratory fish will be lost in this area: sturgeon(Huso,huso), stor sturgeron(Acipenser stellatus),sturgeron(Acipenser sturio).The biological significance of the decrease of migratory fish populations inside the area of the artificial pools is obvios.The two pools from the two Iron Gates just close their migration way to their reproduction area which was the Iron Gates zone,very well aerated,the oxygen being the basic condition for their breeding.The burbot(Lota lota) which was plentiful dowstream the pool from Iron Gates I vanished.
Also decreased the population of the strlot species(Acipenser ruthenus).On days it is pointed out only upstream the pool from Iron Gates I.The oxygen like a limitative ecological factor influenced too the species with heophile tendencies:pike pergh(Stizostedion lucioperca,L.1758),striped pike perch(stizostion volgense,Smalin,1788),bluish barbel(Barbus barbus),meridional barbel(Barbus meridionalis petenyi,Heckel,1847),hake(Vimba vimba carinata,Pallos,18 U),which retired from the area to the end of the pool,where the quantity of oxygen is more important.Modifications were pointed out too at the stagnophile species which put up with the new conditions from the pools but due to increased volume of water they find with difficulty their breeding places so some generations may not appear because of that.
From the rheophile species the broad snout(Chondrostoma nasus nasus) which were plentiful here is lost now.The reseachers also signaled the disappearance of some Danubian species,the Little Danubian fish(Sabanijewia aurata bulgarica),the groundling(Cobitis taenia),which were plentiful.The distruction of the Danubian natural pools which represented the breeding places for fish is the major intervention in the change of the Danube and unfortunately the consequences didn’t delay to appear.
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| Stanciu Adriana - Teacher |
| Tutunaru Daniil - Teacher |
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Electronic zine EkoMAR, you are reading now, is produced in
online cooperation of school teams from three countries
joined together for Europe At School 2001 competition.
Zine is prepared and published with online automated
tools by members of school teams.
Internet and e-z Composer software, newest technologies used here,
are only media and tools, but real gold here is joining
of tens authors of articles spread in three countries and
values of their original works.
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