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16/04/2006
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1658
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Article scientifique 5.0 |
03/12/2008 à 00h17 |
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Je viens de tomber dans Science sur une véritable friandise.
Abstract ci-dessous.
Pour les non anglophones : la baisse de calcium dans l'eau continue. Et les conséquences écologiques et environmentales ne vont faire que s'accentuer.
Indice : le neuf-deux n'est pas le neuf-trois
| | | | | | Citation :
Science. 2008 Nov 28;322(5906):1374-7.
The widespread threat of calcium decline in fresh waters.
Jeziorski A, Yan ND, Paterson AM, Desellas AM, Turner MA, Jeffries DS, Keller B, Weeber RC, McNicol DK, Palmer ME, McIver K, Arseneau K, Ginn BK, Cumming BF, Smol JP.
Paleoecological Environmental Assessment and Research Lab, Department of Biology, Queen's University, Kingston, ON, Canada, K7L 3N6.
Calcium concentrations are now commonly declining in softwater boreal lakes. Although the mechanisms leading to these declines are generally well known, the consequences for the aquatic biota have not yet been reported. By examining crustacean zooplankton remains preserved in lake sediment cores, we document near extirpations of calcium-rich Daphnia species, which are keystone herbivores in pelagic food webs, concurrent with declining lake-water calcium. A large proportion (62%, 47 to 81% by region) of the Canadian Shield lakes we examined has a calcium concentration approaching or below the threshold at which laboratory Daphnia populations suffer reduced survival and fecundity. The ecological impacts of environmental calcium loss are likely to be both widespread and pronounced. |
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Je ne dis pas que ce n'est pas injuste, mais je dis que cela soulage.
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Science-fiction, fantastique, fantasy : Culture SF, toutes les littératures de l'imaginaire
© Culture SF 2003 / 2014 - Conception et réalisation : Aurélien Knockaert - Mise à jour : 08 juin 2014
nos autres sites : APIE People : rencontres surdoués - Traces d'Histoire
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