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2. Introduction to the Special issue of the Canadian Journal of Earth Sciences, "Magmatic and metallogenic processes associated with large igneous provinces".
- Author
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Williamson, Marie-Claude and Saumur, Benoit M.
- Subjects
IGNEOUS provinces ,EARTH sciences ,MINES & mineral resources ,IGNEOUS rocks ,GEOCHEMISTRY ,PETROLOGY - Abstract
Copyright of Canadian Journal of Earth 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.)
- Published
- 2019
- Full Text
- View/download PDF
3. A simplified approach for the historical analysis of urban person travel.
- Author
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Shalaby, Amer S
- Subjects
TRANSPORTATION planning ,TRAVEL ,EMPLOYMENT - Abstract
This paper presents a simplified approach to quantify the contribution of individual factors to the historical growth or decline in total travel between two points in time. The method employs person trip rates and distributions of the individual characteristics at the two time points to determine the portion of urban person travel increase or decrease associated with the change in each factor. The paper presents the application of the approach to investigate changes in person travel in the Greater Toronto Area between 1986 and 1996. Specifically, the study determined the change in person travel attributed to each of the following factors independently: change in population size, change in age distribution, change in residential location distribution, and change in employment status distribution (full time, part time, work at home). The data were obtained from the 1986 and 1996 Transportation Tomorrow Surveys (TTSs).Key words: transportation planning, travel demand.Cet article présente une approche simplifiée afin de quantifier la contribution des facteurs individuels à l'augmentation/diminution historique du nombre total de voyages entre deux points dans le temps. La méthode utilise les taux de déplacements des individus et les distributions des caractéristiques individuelles aux deux points dans le temps afin de déterminer l'augmentation/diminution de la portion des déplacements des individus en ville associée au changement de chaque facteur. Ensuite, l'article présente l'application de l'approche afin d'étudier les changements des déplacements des individus dans le Grand Toronto entre 1986 et 1996. Plus particulièrement, l'étude a déterminé que le changement dans les déplacements des individus est attribué à chacun de ces facteurs indépendants, soit le changement dans la taille de la population, le changement dans la distribution de l'âge, le changement dans la distribution des locations résidentielles et le changement dans la distribution du statut d'emploi (temps plein, temps partiel, travail à la maison). Les données ont été obtenues dans le Transportation Tomorrow Surveys (TTS) de 1986 et 1996.Mots clés : planification des transports, demande de déplacements.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
4. Modelling diameter at breast height distribution of jack pine and black spruce natural stands in eastern Canada.
- Author
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Rijal, Baburam and Sharma, Mahadev
- Subjects
JACK pine ,BLACK spruce ,AUSTRIAN pine ,WEIBULL distribution ,DISTRIBUTION (Probability theory) ,DEAD trees - Abstract
Individual tree diameter at breast height (DBH) distribution is an important information for forest management planning. Forest managers obtain the DBH data either by field measurements or estimations using predictive models. However, probability distribution models are still lacking or need improvement. Therefore, we aimed to construct and fit diameter distribution models that reflect forest structure and composition change. We evaluated gamma, log-normal, and Weibull probability distribution functions (PDFs) for two commercially important tree species, black spruce (Picea mariana (Mill) B.S.P.) and jack pine (Pinus banksiana Lamb), grown in natural stands across Ontario, Canada. We modelled the parameters of the distributions as a function of stand-level variables for these species. We used DBH data from 735 permanent sample plots. Our results showed that all three evaluated PDFs reflected observed DBH distribution. We demonstrated that the moment-based recovered parameters could represent the maximum likelihood-estimated parameters precisely, and parameters of the PDFs can be modelled as a function of stand-level dynamic covariates. The models unbiasedly predicted the PDF parameters DBH means and DBH classes. The R
2 of the model fit ranged between 0.35 and 0.98 for the predicted parameters and 0.90 and 0.97 for the predicted DBH. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
5. Revisiting the origins of glyphosate-resistant giant ragweed (Ambrosia trifida L.) in Canada.
- Author
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Page, Eric R., Martin, Sara, Meloche, Sydney, Thibodeau, Alyssa, Nurse, Robert E., Sikkema, Peter H., Tardif, François J., Cowbrough, Michael J., and Laforest, Martin
- Subjects
RAGWEEDS ,AMBROSIA artemisiifolia ,GLYPHOSATE ,PROLINE - Abstract
Glyphosate-resistant giant ragweed (Ambrosia trifida L.) was first identified in Canada in 2008. Although early studies attributed resistance in this species solely to non-target site mechanisms, the presence of a proline (P) to serine (S) mutation at position 106 of EPSPS2 in common and giant ragweed has recently been reported. The objective of this research was (i) to determine whether a P106S mutation is present in historical samples of giant ragweed seed collected from the site of the first report of glyphosate resistance, and (ii) to determine the frequency and distribution of P106S in resistant and susceptible biotypes collected as part of historical surveys throughout southwestern Ontario. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Sugar maple sap, soil, and foliar chemistry in response to non-industrial wood ash fertilizer in Muskoka, Ontario.
- Author
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Conquer, Shelby M., Yan, Norman D., and Watmough, Shaun A.
- Subjects
WOOD ash ,SUGAR maple ,MAPLE syrup ,FOREST soils ,SOIL horizons - Abstract
Non-industrial wood ash may be an effective forest soil nutrient supplement but its use in Canada is largely restricted because of unknown concentrations of trace metal contaminants. Sugar maple (Acer saccharum Marshall) is particularly sensitive to low soil calcium (Ca) levels, and though maple syrup is of great economic importance in Canada, it is unknown how wood ash could affect sap chemistry. Non-industrial wood ash (NIWA; 6 Mg·ha
−1 ) applied to experimental plots in Muskoka, Ontario was rich in Ca (27%), while metal concentrations were well below provincial regulatory limits. One-year post-application, significant increases were observed in the treated plots in the soil pH and base cations (Ca, K, and Mg) in the surface soil horizons, and metal concentrations in the litter. Sap yield in the control plots was significantly lower in the first-year post-application than in the second year, but no other differences were found. In both tapping years, sap sweetness remained similar and differences in nutrient and metal concentrations between treatments were generally small and inconsistent. Foliar chemistry remained largely unchanged 1 year following application, except for K that was twice as high in the treated plots. Ultimately, NIWA is unlikely to significantly alter sugar maple sap chemistry, indicating that it is a viable nutrient supplement that can enhance soil fertility in sugar bushes with no impact on sap sweetness. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
7. The Potsdam–Beekmantown Group boundary, Nepean Formation type section (Ottawa, Ontario): a cryptic sequence boundary, not a conformable transition.
- Author
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Dix, George R., Hersi, Osman Salad, and Nowlan, Godfrey S.
- Subjects
SEDIMENTATION & deposition ,GEOLOGY ,CAMBRIAN paleoecology ,EARTH sciences - Abstract
Copyright of Canadian Journal of Earth 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.)
- Published
- 2004
- Full Text
- View/download PDF
8. Reply to the discussion by N. Eyles and A. Mohajer on "Analysis and reinterpretation of deformation features in the Rouge River valley, Scarborough, Ontario".
- Author
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Godin, Laurent, Brown, Richard L, Dreimanis, Aleksis, Atkinson, Gail M, and Armstrong, Derek K
- Subjects
VALLEYS ,GLACIERS ,GEOLOGIC faults ,NEOTECTONICS - Abstract
Presents a reply to a comment on the study "Analysis and Reinterpretation of Deformation Features in the Rouge River Valley, Scarborough, Ontario," by N. Eyles and A. Mohajer. Structural analysis of deformation features in relation to local ice flow directions; Interpretation of drumilinoid features; Compatibility of the faults with neotectonic-related or glacial tectonic-related processes.
- Published
- 2003
- Full Text
- View/download PDF
9. THE DUTY TO CONSULT AND ACCOMMODATE ABORIGINAL PEOPLES: A PRIMER FOR ONTARIO SURVEYORS WORKING IN RESOURCES DEVELOPMENT.
- Author
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Townshend, H. W. Roger and McClurg, Michael
- Subjects
- *
ABORIGINAL Canadians , *LEGAL status of indigenous peoples , *INDIGENOUS rights , *MINES & mineral resources , *MINING law , *SURVEYING (Engineering) - Abstract
Aboriginal law has developed to require Aboriginal peoples to be "consulted and accommodated" if their rights may be impacted by a government decision, including a government permit or approval of a project of a private proponent. For example, hunting rights often exist throughout a First Nation's treaty or traditional territory (i.e. far beyond the limits of reserves), and the duty to consult and accommodate can be triggered by mining and other resource development. Contrary to the common understanding of some of those unfamiliar with this area of law, this duty applies not only to activities undertaken under federal authorization, but also to those under provincial authorization. The Crown's "duty to consult and accommodate" Aboriginal peoples has become a central theme in the discussion of natural resource development in Canada. In response to various decisions of Canadian courts, the Government of Ontario significantly overhauled its Mining Act in 2009 to provide for some consultation with Aboriginal communities. Those changes came in to effect in the spring of 2013. This paper will describe the constitutional duty to consult as it has been described and elaborated on by courts in Canada and some of the implications it has for resource extraction in Ontario. It will then undertake a case study discussing Ontario's attempt to respond to its duty to consult by amending the Mining Act regime. Finally, the paper will consider the flaws in the Mining Act and the reasons that exploration companies and surveyors working for them should be prudent and pro-active when undertaking intrusive activities in the traditional territories of Aboriginal peoples. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
10. RECENT BOUNDARY LAW CASES.
- Author
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de Rijcke, Izaak
- Subjects
- *
BOUNDARY disputes , *BOUNDARY laws , *REAL property , *LAND titles , *INLAND navigation laws , *LAND tenure , *ACTIONS & defenses (Law) - Abstract
In this paper, recent boundary cases are considered-but especially as related to Ontario. The choice of jurisdiction is a consequence of the original audience for whom the paper was prepared: real estate lawyers in Ontario. While the activity of case law review and discussion may be seen as an ad hoc and fact-specific exercise, most lawyers in practice choose to remain aware of recent cases in order to stay abreast of new trends. Law schools still use the case law method for teaching-as well as to identify current reported cases as harbingers of potential new trends. Likewise, legislators monitor what emerges from our courts-if only to make sure that there is not a need for remedial legislation in order to possibly "correct" policy implications of a decision or a series of decisions which signal a new trend. Despite its jurisdictional limitations and the review of only most recent cases, this paper is both an example and a reminder that the jurisprudence of boundary law and the work of geomatics professionals continues to evolve. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
11. Traffic and speed characteristics on two-lane highways: field study.
- Author
-
Hassan, Yasser
- Subjects
AUTOMOBILE speed ,TRAFFIC flow ,ROAD construction ,HIGHWAY engineering ,ACCELERATION (Mechanics) - Abstract
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.)
- Published
- 2003
- Full Text
- View/download PDF
12. Application of seismic stratigraphy and sedimentology to regional hydrogeological investigations: an example from Oak Ridges Moraine, southern Ontario, Canada.
- Author
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Sharpe, D. R., Pugin, A., Pullan, S. E., and Gorrell, G.
- Subjects
HYDROGEOLOGY ,SEDIMENTOLOGY ,SEISMIC prospecting ,STRATIGRAPHIC geology ,OAK Ridges Moraine (Ont.) - Abstract
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.)
- Published
- 2003
- Full Text
- View/download PDF
13. Walkerton: Lessons learned in comparison with waterborne outbreaks in the developed world.
- Author
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Hrudey, S E, Huck, P M, Payment, P, Gillham, R W, and Hrudey, E J
- Subjects
CONTAMINATION of drinking water ,WATER pollution ,AQUATIC microbiology ,WATERBORNE infection - Abstract
An estimated 2300 people became seriously ill and 7 died from exposure to microbially contaminated drinking water in the town of Walkerton, Ontario, in May of 2000. The severity of this drinking water disaster resulted in the Government of Ontario calling a public inquiry by Mr. Justice Dennis O'Connor to address the cause of the outbreak, the role, if any, of government policies in contributing to this outbreak, and ultimately, the implications of this experience on the safety of drinking water across the province of Ontario. This paper summarizes relevant evidence presented at the inquiry by the expert panel together with Justice O'Connor's findings addressing the circumstances of the outbreak. These findings are reviewed in relation to the published causes of previous waterborne disease outbreaks that have been reported elsewhere in developed countries. The circumstances surrounding the Walkerton tragedy are an important source of knowledge for those concerned with providing safe drinking water to the public. Although some circumstances are obviously specific to this epidemic, others echo common themes in waterborne outbreaks that have occurred before. These common themes suggest the need for attention to broad issues of drinking water safety in addition to the individual specific details that often command attention. Key words: waterborne disease, Escherichia coli O157:H7, Campylobacter jejuni, Cryptosporidium, Giardia, multiple barriers, health risk.Environ 2300 personnes sont devenues gravement malades et sept personnes sont décédées à la suite d'une exposition à de l'eau potable contaminée par voie microbienne dans la ville de Walkerton, en Ontario, en mai 2000. La gravité de ce désastre d'eau potable a fait que le gouvernement de l'Ontario a lancé une enquête publique, menée par M. le juge Dennis O'Connor, visant à déterminer la cause de cette éclosion, la contribution, s'il y a en une, des politiques gouvernementales à cette éclosion et, en bout de ligne, les répercussions de cette expérience sur la salubrité de l'eau potable partout en Ontario. Cet article résume les preuves pertinentes présentées à l'enquête par le panel d'experts et les conclusions du juge O'Connor sur les circonstances de cette éclosion. Ces conclusions sont revues à la lumière des causes publiées touchant les éclosions antérieures de maladies hydriques qui ont été rapportées ailleurs dans les pays développés. Les circonstances entourant la tragédie de Walkerton sont une source importante de connaissances pour les compagnies fournissant de l'eau potable salubre au public. Bien que certaines circonstances sont évidemment spécifiques à cette épidémie, d'autres font penser à des thèmes communs aux éclosions hydriques survenues auparavant. Ces thèmes communs suggèrent le besoin de porter attention aux grandes questions de la sécurité de l'eau potable en plus des détails uniques spécifiques qui doivent souvent être examinés. Mots clés : maladie hydrique, Escherichia coli O157:H7, Campylobacter jejuni, Cryptosporidium, Giardia, barrières multiples, risque pour la santé. [Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]
- Published
- 2002
- Full Text
- View/download PDF
14. Scale model testing and calibration of City of Ottawa sewer weirs.
- Author
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Bettez, J, Townsend, R D, and Comeau, A
- Subjects
WEIRS ,WATER storage ,HYDRAULIC structures ,SEWERAGE - Abstract
This paper reports the results of a laboratory study of the effects of (i) manhole proximity to installation site, (ii) pipe slope (i.e., approach velocity), (iii) upstream head measurement location, and (iv) submergence on the "hydraulics" of two types of sewer weirs used by the City of Ottawa. The City's streamlined form of broad-crested weir and its compound-shaped sharp-crested weir were initially calibrated for a "pipe straight"-arrangement (no upstream manhole is present) for a wide range of flow conditions at 0.2%, 0.4%, and 1.0% pipe slopes. The calibration tests were then repeated with the weirs positioned immediately downstream of a model manhole structure ("manhole"-arrangement). Corresponding data sets were compared to determine the effects of (i) approach velocity and (ii) manhole proximity (for two different shapes of manhole "benching") on the respective weir discharge coefficients.Key words: sewer weirs, broad-crested weir, compound sharp-crested weir, calibration, sewer benching, discharge coefficients.Cet article rapporte les résultats d'une étude en laboratoire sur les effets de : (i) la proximité des bouches d'égout du site d'installation, (ii) la pente des conduites (i.e., vélocité d'approche), (iii) l'emplacement des mesures de la hauteur de la colonne d'eau en amont, et (iv) la submersion sur « l'hydraulique » de deux types de crêtes pour égouts utilisés par la ville d'Ottawa. Les profils d'écoulement des crêtes rectangulaires de la ville et de ses crêtes triangulaires on été calibrés au départ pour un arrangement de « conduites droites » (aucune bouche d'égout présente en amont), pour une variété de conditions d'écoulement ayant des pentes de conduites de 0,2%, 0,4% et 1,0%. Les tests de calibration ont été répétés avec les crêtes positionnées immédiatement en aval d'un modèle d'une structure de bouche d'égout (arrangement « bouche d'égout »). Les banques de données correspondantes ont été comparées afin de déterminer les effets de : (i) la vélocité d'approche, et (ii) la proximité de la bouche d'égout (pour deux types différents de formes de bouche d'égout) sur les coefficients d'écoulement des crêtes respectives.Mots clés : crêtes pour égouts, crête rectangulaire, crête triangulaire, calibration, structure de support pour égouts, coefficients de déversement.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]
- Published
- 2001
- Full Text
- View/download PDF
15. Marine and freshwater centrohelid heliozoans (Haptista: Centroplasthelida) in Canada, including taxonomic revisions and descriptions of 22 new species and subspecies.
- Author
-
Nicholls, Kenneth H.
- Subjects
SUBSPECIES ,TERRITORIAL waters ,FRESH water ,FRESHWATER habitats ,SPECIES - Abstract
Canadian coastal waters of the Pacific Ocean and the Atlantic Ocean as well as inland freshwater habitats in Ontario were sampled for centrohelid heliozoans (free-living heterotrophic single-celled organisms) over a period of nearly five decades. More than 60 species and subspecies were revealed, including 1 Triangulopteris, 1 Raphidocystis, 2 Pseudoraphidocystis, 3 Raineriophrys, 4 Pseudoraphidiophrys, 12 Choanocystis, 15 Pterocystis, and 25 Acanthocystis taxa. Of these, 22 were officially named and described as new to science based primarily on the morphology of the siliceous scales that cover the cell. New species were compared with images and/or descriptions of close "relatives" to validate their new species assignments. New data on five species of Acanthocystis and one species of Choanocystis required revisions of their descriptive taxonomy that in some cases resulted in the splitting off of separate species or subspecies. Very little can be concluded about global distribution of centrohelid heliozoans, owing to the paucity of records. For many of the taxa reported here, previous records consist of just one or two findings from other parts of the world. One example is Choanocystis antarctica Tikhonenkov and Mylnikov, 2011 that was previously known only from Antarctic seawater, but is reported here from an Ontario softwater lake. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
16. Susceptibility of endangered Cornus florida (eastern flowering dogwood) to the introduced fungal pathogen Discula destructiva (dogwood anthracnose) in the Canadian Carolinian forest: insights from environmental, ecological, and population genetics assessments
- Author
-
Mitchell, Emily, Fleming, Sage, Dorken, Marcel, and Freeland, Joanna
- Subjects
POPULATION genetics ,DOGWOODS ,GENETIC variation ,FRAGMENTED landscapes ,GENE flow ,HABITATS ,PLANT dispersal - Abstract
Forest fragmentation and introduced pathogens are negatively impacting trees and forests globally, including the Carolinian forest of southern Ontario, Canada. Multiple species at risk live in this threatened but biodiverse forest, including the endangered Cornus florida (eastern flowering dogwood), which is now limited to fragmented woodlots, and has been decimated by the introduced fungal pathogen Discula destructiva (dogwood anthracnose). Ongoing management of C. florida in Canada is challenged by multiple knowledge gaps, two of which we aimed to address in this study. We first evaluated the association between anthracnose disease prevalence and a suite of ecological and environmental variables across 21 sites. Across our sites, larger trees tended to have the highest disease incidence, and trees on shallow slopes had the most crown dieback. We then quantified genetic diversity and gene flow, and found that genetic structure has not been substantially impacted by habitat fragmentation, although dispersal typically covers short distances. However, genetic diversity is relatively low in smaller populations and in younger trees. Localized dispersal and eroding genetic diversity may limit future adaptation and hence exacerbate population declines. We recommend that managers prioritize plantings in small populations, avoid shallow slopes, and track younger trees to evaluate age-related mortality. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
17. Use of two novel trailer types for transportation of pigs to slaughter. II. Effects on trailer microclimate, pig behaviour, physiological response, and meat quality under Canadian winter conditions.
- Author
-
Moak, Kyle A.T., Bergeron, Renée, Conte, Sabine, Bohrer, Benjamin M., Ferreira, Guilherme Agostini, Vero, Jessica Gonçalves, Aboagye, Gizella, Arrazola, Aitor, Devillers, Nicolas, and Faucitano, Luigi
- Subjects
MEAT quality ,SWINE ,CREATINE kinase ,ANIMAL welfare ,WINTER ,HUMIDITY ,TRAILERS - Abstract
Copyright of Canadian Journal of Animal Science 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.)
- Published
- 2022
- Full Text
- View/download PDF
18. Seismic performance assessment of an existing multispan bridge in eastern Canada retrofitted with fiber reinforced elastomeric isolator.
- Author
-
Fosoul, Saber A.S. and Tait, Michael J.
- Subjects
ELASTOMERIC fibers ,CONTINUOUS bridges ,BRIDGE abutments ,GROUND motion ,SOIL mechanics ,FINITE element method ,RETROFITTING ,METALLIC composites - Abstract
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.)
- Published
- 2022
- Full Text
- View/download PDF
19. Occupancy and detection of Wavyrayed Lampmussel (Lampsilis fasciola) in Ontario, Canada1.
- Author
-
Lamothe, Karl A., McNichols-O'Rourke, Kelly A., and Morris, Todd J.
- Subjects
FASCIOLA ,SPECIES distribution ,FRESHWATER mussels ,BIVALVES ,UNIONIDAE - Abstract
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.)
- Published
- 2021
- Full Text
- View/download PDF
20. Holocene paleoclimate and paleoecology determined from fossil Coleoptera at Brampton, Ontario, Canada.
- Author
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Motz, John E and Morgan, Alan V
- Subjects
PALEOECOLOGY ,FOSSILS ,BEETLES - Abstract
An unusually rich and extensive 5 m sequence of organic-rich sediments (ca. 13 000 to ca. 4500 BP) from a drained glacial kettle near Brampton, Ontario, has produced a large and varied assemblage of fossil insects. Coleoptera (beetles) from the base include species typical of northern boreal or tree line habitats today. Approximately one metre above the base of the section (ca. 11 500 BP), there is an abrupt appearance of numerous bark beetles (family Scolytidae) and other Coleoptera that inhabit boreal forests. Temperate species whose ranges are predominantly or totally south of the Ontario border, appear, beginning at ca. 9500 BP, suggesting environmental conditions similar to modern ones. Younger Dryas and Pre-Boreal Oscillation cold events may be evident in lower parts of the boreal sequence, although considerations of temporal and climatic resolution make interpretation somewhat ambiguous.Une séquence exceptionnellement féconde et vaste de sédiments riches en matière organique (vers 13 000 à vers 4 500 BP) s'étend sur une hauteur 5 m dans une marmite glaciaire drainée près de Brampton en Ontario; cette séquence a fourni un grand assemblage varié d'insectes fossiles. Les Coléoptères à la base comprennent des espèces typiques des présents habitats boréals du nord ou de la limite des arbres d'aujourd'hui. Environ un mètre au-dessus de la base (vers 11 500 BP) il y a une apparition soudaine de nombreux scolytes (famille des Scolytidae) et d'autres Coléoptères qui habitent les forêts boréales. Les espèces tempérées dont les étendues sont surtout ou entièrement au sud de la frontière de l'Ontario, semblent débuter vers 9 500 BP, suggérant des conditions environnementales semblables aux conditions modernes. Des événements de froid du Dryas récent et de l'oscillation préboréale peuvent être évidents dans les parties inférieures de la séquence boréale, bien que les considérations de résolution temporelle et climatique rendent l'interprétation quelque peu ambiguë.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]
- Published
- 2001
- Full Text
- View/download PDF
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