HR: 11:00h
AN: NB52F-03    [Abstracts]
TI: Changes in Benthic Macroinvertebrate Communities in Relation to Water Chemistry in 17 Lakes in South-Central Ontario, Canada
AU: * Lento, J
EM: jlento@gmail.com
AF: Environmental & Resource Science, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8 Canada
AU: Dillon, P
EM: pdillon@trentu.ca
AF: Environmental & Resource Science, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8 Canada
AU: Somers, K
EM: keith.somers@ene.gov.on.ca
AF: Dorset Environmental Research Centre, P.O. Box 39 1026 Bellwood Acres Dr., Dorset, ON P0A 1E0 Canada
AB: Benthic macroinvertebrates can be strong indicators of lake conditions, integrating the effects of all physical and chemical aspects of the environment. In lake systems that have been exposed to acid deposition, benthic community structure may be impacted by changes in water chemistry associated with either acidification or subsequent recovery. Multivariate analysis was used to examine temporal changes (from 1988 to 2002) in the benthic macroinvertebrate communities of 17 acid-sensitive lakes to evaluate the relationship between benthic community structure and water chemistry associated with acidification. Over the 15 years, chemical variables were found to explain 45-87% of the total variation in the benthic community. Temporal changes in community structure were most apparent from 1991 to 1999, while chemical parameters explained the greatest amount of variance from 1993 to 1997. During this period, relationships were evident between specific invertebrate groups and a number of chemical parameters, with covariables such as calcium and sodium often explaining significant additional variation. Overall, the correlation between benthic community structure and water chemistry suggests a strong association between temporal changes in the macroinvertebrate community and changes in lake chemistry associated with acidification and gradual recovery.
DE: 1800 HYDROLOGY
DE: 9901 NABS Student Award - Basic Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly