Although the watersheds of the Petite Cascapedia and Bonaventure Rivers, Gaspe Peninsula, have broadly similar geology and land use, their segment-scale river geomorphology is contrasted by subtle differences in valley characteristics that are a legacy of their individual geomorphic histories. These differences have consequences on the distribution of Atlantic salmon habitat such as boulder abundance (for parr rearing and overwintering habitats) and spawning substrate quality. Parr preference for boulder-rich river segments (1--5 km) was observed in the Bonaventure River. In the study systems redd distribution was sensitive to relatively small changes in the fines content of riffle substrate. River segments flowing through moderately narrow semi-alluvial valleys present better overall parr habitat (high boulder abundance) and better spawning substrate quality (percentage of sand) than wider valley sections. These differences are due to additional sources of coarse sediment, higher shear stresses, and lower bank erosion rates in such valleys.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.33743 |
Date | January 2001 |
Creators | Coulombe Pontbriand, Moise. |
Contributors | Lapointe, Michel (advisor) |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Master of Science (Department of Geography.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001872803, proquestno: MQ78860, Theses scanned by UMI/ProQuest. |
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