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Journal of Environmental Informatics

Online ISSN 1684-8799 / Print ISSN 1726-2135



   Volume 16   Number 1   September  2010 = non-subscribed


JEI 16(1)2010, Pages 1-10  

© 2010 ISEIS. All rights reserved.

Geospatial Analysis of Zinc Contamination in Lake Ontario Sediments

K. W. Forsythe1*, K. Paudel1 and C. H. Marvin2

  1. Department of Geography, Ryerson University, 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
  2. Aquatic Ecosystem Management Research Branch, National Water Research Institute, Environment Canada, Burlington, Ontario L7R 4A6, Canada

*Corresponding author. Tel: +1-416-9795000 Ext.7141 Fax: +1-416-9795362 Email:



This study analyzed zinc contamination concentrations in Lake Ontario sediments. While trace amounts of zinc are important for overall biotic health, large quantities can lead to toxic ecosystem contamination. The data that were utilized in this research were collected as part of the Environment Canada Gr eat Lakes Sediment Assessment Program. Geospatial analysis has become increasingly important when examining spatial trends. A GIS-based kriging technique was utilized to interpolate contamination estimates between sampling locations. The Canadian  federal government specifies the Threshold Effect Level (TEL) and Probable Effect Level (PEL) for sediment contamination. The  TEL refers to the concentration below which adverse biological effects are expected to occur rarely, while the PEL defines the level above which adverse biological effects are expected to occur frequently. The historical and contemporary results indicate that areas of the lake have zinc concentrations that are above the PEL and represent a degree of enrichment of roughly twice the historical background levels. These are mostly associated with the major depositional basins in Lake Ontario with the southern parts of lake having higher concentrations than those in the north. This is related to the eastward flowing current along the southern shore which act s to transport contaminants from Canadian and American industrial estates towards the depositional basins, and bathymetry as the three primary deep-water depositional basins extend much closer  to the southern shoreline, compared to the northern shoreline. The kriging analysis has provided an  additional communication tool and means of influencing management options and decisions.

Keywords: GIS, lake Ontario, log-normalization, ordinary kriging, sediment contamination, zinc


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