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The first Lithoprobe transect in 1984 across Vancouver Island had primary objectives to define the structure associated with subduction and constraints on the potential for great thrust earthquakes. The Lithoprobe results and the comprehensive multidisciplinary data collection and analyses that followed provide compelling evidence for past great earthquakes along the Cascadia subduction zone from Vancouver Island to northernmost California, and for present elastic strain build up toward future great events. There is evidence of sudden coastal subsidence up to 2 m and of deep-sea turbidite deposits indicating strong shaking from huge earthquakes at irregular intervals averaging about 500 years, the last in 1700. Precision geodetic measurements define the present buckling of the coastal region, diagnostic of elastic strain accumulation on a locked thrust fault. The landward extent of rupture and, therefore, shaking at coastal cities is constrained by (i) the pattern of elastic strain buildup, (ii) the estimated temperatures on the fault, (iii) the updip limit of episodic tremor and slip (ETS), (iv) the downdip change in reflection character of the thrust, and (v) the magnitude of coastal subsidence in the most recent, 1700, and previous great events. The major earthquakes are very large, M9, rupturing most of the Cascadia margin, but mainly offshore, limiting somewhat the shaking at inland cities but producing large tsunamis. The ETS that occurs at intervals of just over a year appears to involve slow slip on the subduction thrust downdip of the rupture zone that increases stress on the locked zone and may indicate time varying potential for great events. Les principaux objectifs du premier transect Lithoprobe traversant l’île de Vancouver en 1984 étaient de définir la structure associée à la subduction et les contraintes sur le potentiel de grands tremblements de terre par chevauchement. Les résultats Lithoprobe, et la collecte et l’analyse des très vastes données multidisciplinaires qui en ont découlé, fournissent des évidences convaincantes pour d’anciens grands tremblements de terre le long de la zone de subduction Cascadia, de l’île de Vancouver à l’extrémité nord de la Californie, et pour l’actuelle contrainte de déformation élastique qui s’accumule pour causer de futurs grands événements. Il existe des preuves d’une soudaine subsidence de la côte atteignant 2 m et la déposition de dépôts de turbidites dans les grands fonds océaniques, ce qui indique de fortes secousses de grands tremblements de terre à des intervalles irréguliers, d’une moyenne d’environ 500 ans, le dernier ayant eu lieu en 1700. Des mesures géodésiques précises définissent le flambage actuels de la région de la côte, diagnostiquant une accumulation de contraintes de déformation élastique sur une faille chevauchante figée. L’étendue de rupture vers le continent, et donc le tremblement aux villes côtières, est limitée par (i) les tendances d’accumulations de contraintes de déformation élastique, (ii) la température estimée de la faille, (iii) la limite en amont-pendage de trémors et de glissements épisodiques (TGÉ), (iv) le changement en aval-pendage du caractère de réflexion du chevauchement et (v) la magnitude de la subsidence côtière lors des grands évé nements les plus récent, ceux de 1700 et les anciens. La plupart des principaux tremblements de terre sont très gros, M9, brisant la plus grande partie de la bordure Cascadia surtout; cependant, au large, limitant quelque peu le tremblement aux villes internes mais produisant de grands tsunamis. Les TGÉqui se produisent à des intervalles légèrement supérieurs à un an semblent impliquer un glissement lent sur le chevauchement de la subduction en aval-pendage de la zone de rupture, ce qui augmente progressivement les contraintes sur la zone figée; ils pourraient aussi indiquer un potentiel, variable dans le temps, pour de grands événements. [ABSTRACT FROM AUTHOR]

Different ovipositor characteristics among parasitoid species that share similar niches are associated with different wasp life histories and selective pressures. The length of wasp ovipositors, for example, can determine the accessibility of hosts that feed at different depths within food substrates. Two parasitoids, Ganaspis brasiliensis and Leptopilina japonica (Hymenoptera, Figitidae), which attack Drosophila suzukii (Diptera, Drosophilidae) in their native range, have been investigated for their suitability for the global biological control of the small fruit pest. Despite their sympatry in microhabitat, the parasitoids have differing host ranges, and D. suzukii parasitism rates by each parasitoid species appear to depend on the fruit species occupied by the host species. Adventive populations of both parasitoids have been detected in the Pacific Northwest of Canada and the United States where they can be found parasitizing D. suzukii larvae in crop and non-crop fruits. We dissected and measured the ovipositors of parasitoids reared from three species of fresh fruits at three sites in southwestern British Columbia, Canada, and investigated the influence of parasitoid species, fruit type, and collection site on ovipositor characteristics. We found that ovipositor length differed markedly between the two parasitoid species and between sites while ovipositor width, and stoutness, differed only between the two parasitoid species, but did not vary among sites or fruit hosts. We discuss how ovipositor morphology traits could be associated with differences in life history and host ranges in the two parasitoid species. [ABSTRACT FROM AUTHOR]

Terzaghi (Geotechnique 12 (1962) 251) and Young (Young, A., 1972. Slopes. Oliver and Boyd, Edinburgh, 288 pp.) described the stable forms of slopes in sedimentary rock masses, assuming penetrative discontinuities, which are parallel to bedding and joints which are perpendicular to bedding. The only movements considered were slides along bedding. Experience in the Canadian Rockies indicates that the cohesionless rock masses that exist at or above tree line may also move by toppling, buckling and sliding along joints. These processes also act to limit the inclinations of stable slopes. Rock strength is a factor in the critical height of a slope that buckles. The processes can be represented as fields on a process diagram, a plot of slope inclination against bedding dip, using the basic friction angles of the rocks present.The process diagram also separates five common mountain peak shapes, which form on homoclinal sequences of beds. Castellate and Matterhorn mountains occur in sub-horizontal beds, cuestas develop in gently to moderately dipping beds. Hogbacks formed in moderately to steeply dipping beds have similar slope angles on both cataclinal and anaclinal slopes. Dogtooth mountains occur in steeply dipping sub-vertical beds. [Copyright &y& Elsevier]

A deflection of the fault controlled southwestern coastline of Vancouver Island suggests the presence of a minor orocline, with a Southern Crustal Block (south of Barkley Sound–Alberni Inlet) rotated 20° counterclockwise relative to a Northern Fixed Crustal Block about a pole of rotation located northeast of Port Alberni. In this paper two models of orocline development, one of pure block rotation and one of pure bending, are proposed. The predictions of these models are tested against available geological maps, structural orientation data, identified regions of extension and contraction, and paleomagnetic data. Structural orientation and paleomagnetic data are consistent with 18° of post-Late Cretaceous counter clockwise rotation of the Southern Crustal Block relative to the Northern Fixed Crustal Block. A southward increase in the magnitude of rotation evident in the structural orientation data argues for a model of bending. Both bending and block rotation models predict the development of a zone of contraction along the northeast margin of the Southern Crustal Block, coincident with the location of the Eocene Cowichan fold-and-thrust belt, that diminishes northward toward the pole of rotation. As predicted, the fold-and-thrust belt is characterized by a northerly decrease in the amount of shortening, from >30% at the south end of the thrust belt, to 0% shortening north of Port Alberni. The northerly decrease in shortening is complemented by a north to south change in structural style from cylindrical to conical folds, and finally to planar, undeformed strata. The model of block rotation predicts the presence of a zone of extension extending southwest from the zone of rotation, coincident with the location of Eocene extensional structures within Barkley Sound and with horst and graben structures in the offshore Eocene to Miocene Tofino basin. Extension is less than predicted by a model of pure block rotation and suggests that much of the oroclinal rotation was accommodated by bending. Timing constraints indicate that orocline development was coeval with, and resulted from, the Eocene accretion of seamounts of the Crescent terrane. These findings demonstrate that oroclinal orogeny, the buckling of a linear crustal beam about vertical axes of rotation, can significantly impact the geometry, structure and character of an orogenic belt, even where the buckles are minor (<20° of rotation). [Copyright &y& Elsevier]

The seismic response of a continuous 4-span bridge designed according to the current Canadian seismic provisions is investigated using Incremental Dynamic Analysis (IDA). Different earthquake types, including shallow crustal events, interface Cascadia subduction, and deep inslab subduction are considered. The median collapse capacities calculated using different record selection methods including Conditional Mean Spectrum (CMS)-based, Uniform Hazard Spectrum (UHS)-based, and epsilon-based methods are compared. The use of the epsilon-based method generally resulted in the highest collapse capacity predictions, but the CMS-based method was less sensitive to the number of records considered in the IDA. [ABSTRACT FROM PUBLISHER]

Copyright of Canadian Journal of Fisheries & Aquatic Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ecological theory of adaptive radiation states that differences in ecological circumstances among local populations are the cause of divergence that leads to speciation. The role of parasites in contributing to divergence has seldom been considered, despite their ubiquity and known selective effects. The potential for parasites to contribute to divergence between closely related taxa was examined by quantifying the variation in parasite burdens between sympatric three-spined stickleback species ( Gasterosteus aculeatus complex) in two lakes in coastal British Columbia, Canada. In doing so the relative importance of geographical differences between lakes and trophic or microhabitat differences between species within lakes were evaluated. The entire metazoan parasite burdens of a total of 255 limnetic and benthic sticklebacks in Paxton and Priest lakes were assayed over five time points between spring and autumn. Despite their sympatric distributions, there were large differences in parasite burdens between benthic and limnetic sticklebacks within lakes and these were consistent across both lakes. In particular, limnetics suffered greater burdens of the parasites Schistocephalus solidus and Diplostomum scudderi and benthics had much higher burdens of parasitic glochidia (mollusc larvae). Parasite burdens also differed quantitatively between lakes, but in general such differences were less pronounced than those between the stickleback species. The documented differences in parasite burdens between stickleback species have potential to contribute to divergent selection on life history, immunological and secondary sexual characters that could contribute to reproductive isolation between the species. [ABSTRACT FROM AUTHOR]

Abstract: The Canadian province of British Columbia has been widely recognized as the North American leader in employing Design, Build, Finance Operate public–private partnerships to create new public infrastructure. Canada is one of the most decentralized federations in the world. Provinces exercise considerable autonomy and have powerful revenue raising power at their disposal. Although Canadian local governments are generally seen as substantially inferior to the two senior levels of government, those in British Columbia have in fact managed to achieve quite a bit of autonomy due to non-constitutional factors. Large infrastructure projects, for which municipalities and other local government agencies must look to the province for financial support are among the most controversial of issues within the provincial–local government relationship. The introduction of public–private partnerships represents a classic example of a political entrepreneur changing the rules of the game to favour their desired outcomes. In this case, a government leader determined to pursue an infrastructure program that the province lacked the capital to support and the re-structuring of the state along New Public Management lines. However, even though the rule change favoured the Premier''s immediate goals, and allowed him to over-ride much local objection, it can be argued that in the long run neither local governments nor the province have necessarily gained in power by changing the rules of the game. In keeping with the general tenants of the New Public Management, the introduction of public–private partnerships has given precedence to technocratic forms of knowledge, especially those involved with finance and accounting, with the aim of pursuing public goals in the most “economically efficient” manner possible. The flip side is that democratic input is strictly limited to the initial question as to whether or not a project is desirable, not how it can be best achieved or whether, once underway, it still represents a wise move. As a result, if there are any real winners in terms of autonomy, it has been senior public managers at both the provincial and local level and their financial and accounting advisors. These actors have had the range of issues for which they are accountable markedly simplified when it comes to major infrastructure projects, even as the complexity of such projects are increased by the use of public–private partnerships. Evidence is drawn from government documents, news accounts and interviews conducted by the author with senior managers, politicians and appointed board members of local government organizations (a quasi-governmental agency and a regional municipality''s transit authority) as well as a provincial ministry, which acts as a control case. By employing three cases within the same province and the same time-frame, many of the contextual factors that can confound a study of this sort have been held constant for the purpose of comparison. [Copyright &y& Elsevier]

The Liberal government of British Columbia has had more success in terms of the number of public-private partnerships they have managed to initiate than any other provincial government in Canada. Observers (whether they believe that this outcome is positive or negative) agree that part of this success is attributable to the Capital Asset Management Framework. Introduced in the spring of 2002, this is a province-wide set of guidelines that all ministries, agencies and other public organizations seeking a provincial capital contribution must follow. Adherents of the New Public Management (such as the Liberal government) frequently state that public managers ought to be empowered to produce results, and judged by these results, not tied to rigid procedures. With this in mind, this article examines the Capital Asset Management Framework guidelines. The article also explores how the introduction of the Capital Asset Management Framework shifted government leadership on the issue from a transactional to a transformational basis, potentially helping to alleviate the previous difficulties the government had with this issue. Evidence for this analysis is derived from documents, newspapers and trade, interest group and think-tank publications, as well as interviews that the author conducted with public- and private-sector executives in the summer and fall of 2005. Sommaire : Le gouvernement Libéral de la Colombie-Britannique a remporté plus de succès que tout autre gouvernement provincial au Canada, en termes du nombre de partenariats publics-privés qu'il a réussi à lancer. Les observateurs (que ceux-ci pensent que ce résultat soit positif ou négatif) conviennent que ce succès est en partie attribuable au «Cadre de gestion des immobilisations». Lancé au printemps de 2002, ce projet est un ensemble de lignes directrices pour la totalité de la province que doivent respecter tous les ministères, toutes les agences et autres organismes publics cherchant à obtenir des contributions provinciales pour leurs dépenses en capital. Les adhérents à la Nouvelle gestion publique (comme le gouvernement Libéral) déclarent fréquemment que les gestionnaires publics devraient être habilités à produire des résultats, àêtre jugés sur ces résultats, et non pas être liés par des procédures rigides. C'est dans cet état d'esprit que l'article examine les lignes directrices du Cadre de gestion des immobilisations. L'article étudie également en profondeur comment l'introduction du Cadre de gestion des immobilisations a fait basculer l'approche des dirigeants gouvernementaux sur la question d'une base transactionnelle à une base transformationnelle, en aidant éventuellement à alléger les difficultés précédentes que le gouvernement avait rencontrées à cet égard. Les éléments de preuve de cette analyse proviennent de documents, de journaux et de revues spécialisées, de publications de groupes d'intérêts et de groupes de réflexion, ainsi que d'interviews que l'auteur a menées auprès du personnel de direction des secteurs public et privé au cours de l'été et de l'automne 2005. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geotechnical Journal is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Canadian welfare state has changed significantly in the last decade with the federal devolution of policy responsibilities creating opportunities for some provinces to adopt American social policy ideas. Given the expectations of resilience and non-convergence, in the welfare state literature, this article addresses the issues of policy change by demonstrating that the movement of British Columbia's labour and social policy towards international neoliberal norms, including policy examples set in many US jurisdictions, have produced limited convergence. We suggest that this indicates that more change has occurred and is occurring in the Canadian welfare state than the resilience model or comparative public policy literature would indicate. [ABSTRACT FROM AUTHOR]

The ‘ecological opportunity’ hypothesis predicts that when interspecific competition or predation is reduced, populations will exhibit increases in phenotypic variance as a result of colonization and adaptation to vacant or underutilized ecological niches (i.e. character release). We assessed this hypothesis by examining morphological diversity within stickleback populations in 40 undisturbed lakes from six islands off the mid-coast of British Columbia, Canada. Because larger lakes with well-developed littoral and limnetic zones will have greater trophic niche diversity than smaller lakes with only littoral zones, we predicted a positive association between lake size and variation in trophic morphology. Conversely, reduced vertebrate predation in small bog lakes allows increased variance in defensive structures without costs to fitness. Consistent with both predictions, we observed that phenotypic variance in two traits that are involved in feeding (gape width and pectoral fin length) increased with lake size while variability in defence structures (lateral plate number and dorsal spine length) was inversely related to lake size. Moreover, increased variance in defence morphology was accentuated in populations with severe armour reduction (spine loss, decreased plate overlap), another strong indicator of reduced vertebrate predation. In the majority of cases, these patterns were repeatable among islands, independent from the geographical distance between lakes, and arose from a combination of high variance within each of the sexes and increases in sexual dimorphism. These findings suggest that character release can be trait-specific and reflect the combined effects of competition, predation and habitat heterogeneity. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 86, 297–308. [ABSTRACT FROM AUTHOR]

We employed a cultivation-independent approach to examine archaeal diversity along a transient soil salinity gradient at Salt Spring in British Columbia, Canada that is routinely eroded due to heavy, recurrent rainfall. Archaeal 16S rRNA gene libraries were created using DNA extracted from three soil samples collected along this gradient. Statistical comparisons indicated similar archaeal richness across sites but, a significant shift in archaeal community composition along the salinity gradient. Seven distinct phylogenetic groups were represented in soil libraries. Haloarchaea were the most commonly sampled group. Other 16S rRNA sequences were related to uncultured Euryarchaeota and Crenarchaeota or halophilic methanogens. Haloarchaeal diversity was remarkably high in soil of elevated salinity compared with previously characterized haloarchaeal communities. Salt Spring haloarchaea were not closely related to known low-salt adapted/tolerant species, suggesting they may be frequently faced with local mortality as a result of frequent declines in soil salinity. We speculate that ecosystem disturbance – in the form of salinity fluctuations – is one mechanism for maintaining a diverse community of haloarchaea at Salt Spring. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)