Publication Date:
2008-11-29
Description:
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.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Jeziorski, Adam -- Yan, Norman D -- Paterson, Andrew M -- Desellas, Anna M -- Turner, Michael A -- Jeffries, Dean S -- Keller, Bill -- Weeber, Russ C -- McNicol, Don K -- Palmer, Michelle E -- McIver, Kyle -- Arseneau, Kristina -- Ginn, Brian K -- Cumming, Brian F -- Smol, John P -- New York, N.Y. -- Science. 2008 Nov 28;322(5906):1374-7. doi: 10.1126/science.1164949.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Paleoecological Environmental Assessment and Research Lab, Department of Biology, Queen's University, Kingston, ON, Canada, K7L 3N6.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19039134" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Calcium/*analysis
;
Daphnia/*physiology
;
*Ecosystem
;
Food Chain
;
Fresh Water/*chemistry
;
Geologic Sediments
;
Hydrogen-Ion Concentration
;
Ontario
;
Population Dynamics
;
Reproduction
;
Zooplankton/*physiology
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
