Effects of a Shallow Lake Condition Shift on Habitat, Zooplankton, and Yellow Perch Dynamics

Abstract Brook trout and yellow perch collected while surveying New Brunswick and Nova Scotia headwater lakes were analyzed for DDT metabolites, chlordane, hexacyclohexane isomers, hexachlorobenzene, toxaphene and PCB’s. Concentrations of DDT metabolites were much higher from fish taken from lakes in north-central N.B. (200-700 ng/g wet wt) than from fish taken elsewhere (<10 ng/g). Seventy to 90% of the DDT metabolites was DDE. Chlordane (3-13 ng/g) was analyzed in seven trout, six of them from central N.B. areas with intensive agriculture. Isomers of hexachlorocyclohexane were in highest concentration from north-central N.B. (10-20 ng/g), eastern N.S. (5-15 ng/g) and southern N.B. (5-20 ng/g). In most cases, alpha-hexachlorocyclohexane (lindane) was the isomer in highest concentration. Concentrations of hexachlorobenzene in fish tissues was highly variable with no obvious geographic bias. PCB’s were detected in very few fish, and no toxaphene was detected.

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Public Evaluation of Fish Tainting from Pulp and Paper Mill Discharges

Water Science & Technology ◽

10.2166/wst.1992.0035 ◽

1992 ◽

Vol 25 (2) ◽

pp. 57-64

Author(s):

C. G. Jardine

Keyword(s):

Yellow Perch ◽

Action Plan ◽

Pulp Mill ◽

Paper Mill ◽

Pulp And Paper ◽

Salmo Gairdneri ◽

Pulp And Paper Mill ◽

Advisory Committees ◽

Public Advisory ◽

St Lawrence River

As part of the Remedial Action Plan (RAP) programs for the St. Lawrence and Spanish Rivers in Ontario, Canada, tainting evaluations were conducted using members of the Public Advisory Committees (PACs) and the RAP teams. Triangle test sensory evaluations were conducted on caged rainbow trout (Salmo gairdneri) exposed insitu upstream and downstream of the pulp and paper mill diffuser outfalls In the St. Lawrence River only, evaluations were conducted on indigenous yellow perch (Perca flavescens) caught upstream and downstream of the mill discharge . In both locations, the odour of the flesh from the caged trout exposed above the diffuser outfall was not judged significantly different from caged trout exposed downstream of the discharge. However, the indigenous perch caught downstream of the mill in the St. Lawrence River were judged by the panelists to have a significantly more objectionable odour than those caught upstream of the discharge. While the effluent tainting potential appears to have been eliminated in the Spanish River, further studies are required to determine the source and magnitude of tainting concerns in the St. Lawrence River. The sensory test and results reported here provide useful tools for evaluating the tainting potential of pulp mill discharges and for assessing perceived consumer quality of the fish exposed to these effluents.

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Field Observation and Simulation of Sediment Resuspension in a Shallow Lake

Water Science & Technology ◽

10.2166/wst.1988.0211 ◽

1988 ◽

Vol 20 (6-7) ◽

pp. 263-270 ◽

Cited By ~ 4

Author(s):

K. Otsubo ◽

K. Muraoka

Keyword(s):

Numerical Simulation ◽

Shallow Lake ◽

Water Wave ◽

Field Data ◽

Sediment Resuspension ◽

Field Research ◽

Lake Kasumigaura ◽

Bed Erosion ◽

Current Water ◽

Good Agreement

The dispersion and resuspension of sediments in Takahamairi Bay basin of Lake Kasumigaura were studied by means of field research and numerical simulation. The field data on wind direction and velocity, lake current, water wave, and turbidity were shown. Based on these results, we discuss how precipitated sediments were resuspended in this shallow lake. To predict the turbidity and the depth of bed erosion, a simulation model was established for this lake. The calculated turbidity showed good agreement with the field data. According to the simulated results, the turbidity reaches 200 ppm, and the bed is eroded several millimeters deep when the wind velocity exceeds 12 m/s in the lake.

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