| Autor: |
Kelly Potter, Lesley Lovett-Doust |
| Rok vydání: |
2001 |
| Předmět: |
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| Zdroj: |
Ecological Applications. 11:215-225 |
| ISSN: |
1051-0761 |
| DOI: |
10.1890/1051-0761(2001)011[0215:bsqisa]2.0.co;2 |
| Popis: |
Leaf-to-root surface area ratios in Vallisneria americana have been shown to provide a simple and inexpensive relative measure of sublethal effects of organochlorine contamination. The present study was conducted to determine whether this index of surface area could be used as an effective biomonitor of overall site quality in stressed aquatic ecosystems. The leaf-to-root surface area ratio was determined for samples of V. americana collected from 225 microsites within 12 Areas of Concern (environmentally contaminated areas designated by the International Joint Commission) throughout the Laurentian Great Lakes of Ontario. Statistical analyses indicate that 77% of the variation in the surface area index could be attributed to differences among microsites, with only 23% of variation occurring among plants within a microsite. A multiple regression equation was developed for predicting the leaf-to-root surface area ratio from several measures of microsite quality. Significant parameters affecting the surface area ratio included plant density, light intensity, and an index of sediment contamination. In contrast, measures of water contamination did not show any correlation with leaf-to-root surface area ratio. These observations support the hypothesis that V. americana accumulates contaminants primarily from the sediments and that the leaf-to-root surface area ratio can be used to construct contours of point source impact zones in Areas of Concern. The regression model developed here provides a simple, inexpensive means for monitoring overall site quality throughout the Great Lakes. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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