ISSN:
1432-0703
Source:
Springer Online Journal Archives 1860-2000
Topics:
Energy, Environment Protection, Nuclear Power Engineering
,
Medicine
Notes:
Abstract A series of enclosures were placed in an alkaline, prairie parkland pond in Alberta, Canada. Seven enclosures served as controls, 7 were treated with a mid-July application of the carbamate insecticide, carbofuran at 5 Μg/L, and another 7 received a 25-Μg/L application, a range of concentrations that could occur in a shallow pond (⩽1 m deep) following accidental contamination while aerially-spraying adjacent fields for grasshopper control at the recommended rate of 140 g/ha. Macroinvertebrate numbers and biomass were monitored for 7 days prior to and 55 days after treatment. Results are presented for 8 taxa including the amphipod,Hyalella azteca, Chironominae larvae, Tanypodinae larvae, the snails,Physa andHelisoma, the leech,Helobdella stagnalis, damselfly nymphs, and nymphs of the mayfly,Caenis which together accounted for 97% of all the invertebrates collected during the study. At 5 Μg/L, carbofuran had no detectable adverse effects. At 25 Μg/L,H. azteca abundance and biomass declined to 10% and 6%, respectively, of their pre-treatment levels. Chironominae biomass declined to 17% of its pre-treatment level, owing mainly to the sensitivity ofChironomus. Secondary effects were not overt, althoughHelisoma abundance and biomass remained high throughout the post-treatment period in the 25 Μg/L enclosures in contrast to the controls where it declined during this period.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01055346
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