GEOSCAN, résultats de la recherche


TitreBuilding on unstable ground: Identifying physical landscape constraints on infrastructure sustainability and planning in Nunavut communities
AuteurIrvine, M L; Bell, T; Smith, I R
SourceArcticNet Annual Conference Proceedings; 2009 p. 104-105
Séries alt.Secteur des sciences de la Terre, Contribution externe 20090233
RéunionArcticNet sixth annual scientific meeting; Victoria; CA; décembre 8-11, 2009
Sujetsphysiographie; analyse environnementales; sensitivité de terrain; types de paysage; milieu hydrologique; géologie des dépôts meubles/géomorphologie; hydrogéologie
ProgrammeRenforcement de la résilience des communautées canadiennes face aux changements climatiques, Géosciences de changements climatiques
Résumé(disponible en anglais seulement)
Nunavut communities are characterized by youthful and fast growing populations, which have exacerbated an already existing infrastructure deficit and over-crowded housing situation. In response to this problem, rapid infrastructure growth is almost certain to take place, and thus highlights the need for the establishment of sustainable community development plans. Planning in what are typically small, isolated Nunavut communities, however, can differ from the broad multi-faceted approach common to southern communities. Much of the planning focuses simply on basic housing needs, services and rudimentary transportation. Planning in Nunavut communities also needs to reflect the importance and influence that the physical environment, extreme climate, and highly sensitive nature of the landscape has on development. This study presents a model of how constraints imposed by the physical landscape on infrastructure can be assessed and integrated into a planning protocol.
The protocol has been designed and tested using the case study of Clyde River, a community of 820 people, located on the east coast of Baffin Island, Nunavut. Preliminary mapping of the surficial geology and landscape characteristics employed stereo-viewing of historical series of 1:5000 to 1:40 000 scale airphotographs and analysis of high-resolution Quickbird satellite imagery. Delineation of units was primarily based on sediment types, surface expression (geomorphology), hydrology, and disturbances - both natural (periglacial activity, slope processes) and anthropogenic. Fieldwork involved sediment sampling for textural analysis, topographic surveying to generate digital elevation models for terrain analysis, ground probing for active layer measurement, and permafrost coring for ground ice and pore water salinity assessment. Hazard assessment focused on evidence of coastal flooding and erosion, permafrost degradation, drainage network disruptions, and slope instability. Community consultations occurred during all project stages, providing an understanding of local needs, perceptions, and traditional knowledge. Finally, the information was compiled and integrated into a composite constraints map illustrating the spatial distribution of landscape hazards and limitations to community development. The map employed a simple "traffic-light" classification scheme of red, yellow and green to denote areas of high, medium and low planning constraint, respectively.
The application of this protocol in Clyde River illustrates its effectiveness and limitations. Research provided a comprehensive understanding of surficial terrain characteristics, topography, sediment types, and urban hydrology. Permafrost coring provided valuable point data on sub-surface conditions, but landscape conditions and
instrumental limitations precluded assessment from all areas. This limitation could be remedied by applying geophysical techniques such as ground penetrating radar surveys. Environmental parameters impacting terrain stability such as snow drifting and wind direction were not assessed in this project; their inclusion would augment this protocol. This research provides a snapshot of the current terrain conditions in Clyde River. In recognition of climate change, future versions of this protocol should incorporate potential landscape responses to climate variability through downscaling of climate models to facilitate long-term planning. A modified protocol is being created that will be implemented in several other Nunavut communities to augment the integration of the physical environment into community planning assessments.