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No description available.

No description available.

No description available.

Metal-contamination of lakes simplifies food webs and reduces the efficiency of energy transfer to top trophic organisms, such as yellow perch (Perca flavescens). Benthic invertebrate community composition and yellow perch diet, growth and activity levels from lakes along a metal-contamination gradient were used to assess the importance of a naturally diverse prey base for maintaining energy transfer to growing fish, and how this is disrupted by metal-contamination. As perch grow larger, they shift their diet to larger prey; otherwise, the activity costs of foraging for many, small prey, instead of a few large prey, become too high and the fish stop growing. Metal contaminated lakes have less diverse zoobenthic communities, particularly the lack of large bodied invertebrate taxa, forcing perch to rely on smaller benthic prey. Perch from metal-contaminated lakes display slow growth and poor condition during benthivory. Estimates of fish activity, using the activity of the glycolytic enzyme Lactate dehydrogenase in perch white muscle tissue as a proxy, suggest that diet shifts to larger prey lower activity costs and may explain how diet shifts maintain growth efficiency as perch grow larger. Perch from metal-contaminated lakes cannot benefit from the energetic advantages of switching to larger prey and thus exhibit poor growth.

No description available.

At present, little is known concerning the fungi communities inhabiting the Greater Sudbury Region. This study aimed at identifying the fungal species and abundance in limed and unlimed areas contaminated with metals. Samples were collected from the LFH soil layer from Wahnapitae Hydro-Dam, Daisy Lake, Kingsway, Kelly Lake, Hagar, Onaping Falls and Capreol. Limed and unlimed areas were compared for soil metals, pH, fungi diversity, abundance and seasonal soil respiration. Fungi from soil samples were cultured using Sabouraud Dextrose Agar and Malt Extract Agar. A total of 52 fungi species from 34 genera were identified. There was a significantly higher fungal diversity in the limed areas compared to the samples from unlimed sites based on SDA medium data. Fungi abundance followed the same trend. Significantly higher soil respiration rates were recorded for limed sites compared to unlimed sites. Summer soil respiration rates correlated (r = 0.50) with total fungal abundance.