Prehistorical record of cultural eutrophication from Crawford Lake, Canada

Abstract

Research Article| September 01, 2004 Prehistorical record of cultural eutrophication from Crawford Lake, Canada Erik J. Ekdahl; Erik J. Ekdahl 1Department of Geological Sciences, University of Michigan, 2534 C.C. Little Building, Ann Arbor, Michigan 48109-1063, USA Search for other works by this author on: GSW Google Scholar Jane L. Teranes; Jane L. Teranes 2Scripps Institution of Oceanography, University of California–San Diego, La Jolla, California 92093, USA Search for other works by this author on: GSW Google Scholar Thomas P. Guilderson; Thomas P. Guilderson 3Lawrence Livermore National Laboratory, L-397, 7000 East Avenue, Livermore, California 94551, USA Search for other works by this author on: GSW Google Scholar Charles L. Turton; Charles L. Turton 4Royal Ontario Museum, 100 Queens Park, Toronto, Ontario M5S 2C6, Canada Search for other works by this author on: GSW Google Scholar John H. McAndrews; John H. McAndrews 5Departments of Botany and Geology, University of Toronto, Toronto, Ontario M5S 3B2, Canada Search for other works by this author on: GSW Google Scholar Chad A. Wittkop; Chad A. Wittkop 6Limnological Research Center, Department of Geology and Geophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA Search for other works by this author on: GSW Google Scholar Eugene F. Stoermer Eugene F. Stoermer 7School of Natural Resources, University of Michigan, Ann Arbor, Michigan 48109, USA Search for other works by this author on: GSW Google Scholar Geology (2004) 32 (9): 745–748. https://doi.org/10.1130/G20496.1 Article history received: 20 Jan 2004 rev-recd: 14 May 2004 accepted: 18 May 2004 first online: 03 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Erik J. Ekdahl, Jane L. Teranes, Thomas P. Guilderson, Charles L. Turton, John H. McAndrews, Chad A. Wittkop, Eugene F. Stoermer; Prehistorical record of cultural eutrophication from Crawford Lake, Canada. Geology 2004;; 32 (9): 745–748. doi: https://doi.org/10.1130/G20496.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Cultural eutrophication—the process by which human activities increase nutrient input rates to aquatic ecosystems and thereby cause undesirable changes in surface-water quality—is generally thought to have begun with the start of the industrial era. The prehistoric dimension of human impacts on aquatic ecosystems remains relatively undescribed, particularly in North America. Here we present fossil plankton data (diatoms and rotifers), organic and inorganic carbon accumulations, and carbon isotope ratios from a 1000 yr sediment core record from Crawford Lake, Ontario, Canada. The data document increased nutrient input to Crawford Lake caused by Iroquoian horticultural activity from A.D. 1268 to 1486 and show how this increased nutrient input elevated lake productivity, caused bottom-water anoxia, and irreversibly altered diatom community structure within just a few years. Iroquoian settlement in the region declined in the fifteenth century, yet diatom communities and lake circulation never recovered to the predisturbance state. A second phase of cultural eutrophication starting in A.D. 1867, initiated by Canadian agricultural disturbance, increased lake productivity but had comparatively less impact on diatom assemblages and carbon-storage pathways than the initial Iroquoian disturbance. This study deepens our understanding of the impact of cultural eutrophication on lake systems, highlights the lasting influence of initial environmental perturbation, and contributes to the debate on the ecological impacts of density and agricultural practices of native North American inhabitants. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.