Title

Zoobenthic community composition and chironomidae (diptera) mouthpart deformities as indicators of sediment contamination in the Lake Huron-Lake Erie Corridor of the Laurentian Great Lakes

Date of Award

2008

Degree Type

Thesis

Degree Name

M.Sc.

Department

Biological Sciences

First Advisor

Ciborowski, Jan (Biological Sciences)

Keywords

Biology, Ecology.

Rights

CC BY-NC-ND 4.0

Abstract

Zoobenthos are widely used indicators of ecological quality, integrating changes in habitat condition over time. This thesis investigated community composition and incidence of larval chironomid mouthpart deformities to assess benthic condition in the Lake Huron-Lake Erie Corridor. To test the "Reference-Degraded Continuum" multivariate approach of zoobenthic community assessment, a series of analyses were used to identify two unique groupings of least-contaminated reference sites, each with characteristic relative abundances of zoobenthic genera and associated habitat features. Statistically significant negative relationships between biological condition and sediment contamination were found for each group. Indicator taxa were identified. Six of 43 Chironomidae genera were assessed for mouthpart deformities. Overall incidence of deformities varied from 0.57 to 5.88 among zones. Only ' Chironomus' exhibited significant among-zone variation, reflecting gross levels of sediment contamination. The combined use of community and individual indicators was more diagnostic of benthic habitat quality than use of either approach alone.