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1
LOTZ, L. N. "Present status of Sicariidae (Arachnida: Araneae) in the Afrotropical region." Zootaxa 3522, no. 1 (October 19, 2012): 1. http://dx.doi.org/10.11646/zootaxa.3522.1.1.
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In this paper the present state of knowledge of the family Sicariidae in the Afrotropical region is discussed. The Sicariidaein the Afrotropical region, as it stands at present, consists of two genera, viz. Sicarius Walckenaer, 1847 (subfamilySicariinae) with six species: S. albospinosus Purcell, 1908, S. damarensis Lawrence, 1928, S. dolichocephalus Lawrence,1928, S. hahni (Karsch, 1878), S. spatulatus Pocock, 1900, and S. testaceus Purcell, 1908 and Loxosceles Heineken &Lowe, 1835 (subfamily Loxoscelinae) with 13 species: L. fontainei Millot, 1941, L. foutadjalloni Millot, 1941, L. lacroixiMillot, 1941, L. meruensis Tullgren, 1910, L. neuvillei Simon, 1909, L. pallidecolorata (Strand, 1906), L. parramiNewlands, 1981, L. rufecens (Dufour, 1820), L. smithi Simon, 1897, L. speluncarum Simon, 1893, L. spinulosa Purcell,1904, L. valida Lawrence, 1964 and L. vonwredei Newlands, 1980. Loxosceles parrami Newlands, 1981 is here renamedto L. parramae (Newlands, 1981), as it was named for a Miss Parram. Loxosceles valida Lawrence, 1964 is heretransferred to the genus Drymusa Simon, 1893 (Drymusidae) and three species of Loxosceles is revalidated (L. bergeri Strand, 1906, L. pilosa Purcell, 1908 and L. simillima Lawrence, 1927).
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Beaulieu, Jean, and Jean-Pierre Simon. "Variation in cone morphology and seed characters in Pinus strobus in Quebec." Canadian Journal of Botany 73, no. 2 (February 1, 1995): 262–71. http://dx.doi.org/10.1139/b95-029.
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To investigate the patterns of variation in white pine (Pinus strobus L.), 10 natural populations from Quebec were compared using the phenotypic variation of cone and seed traits. Eight characters were measured on 10 cones collected from 30 trees in each of the 10 sampled populations. Four populations were from the Ottawa River region and four from the St. Lawrence Lowlands region, while two populations were at the margin of the natural range of the species in Quebec, from the Abitibi region and Anticosti Island. Significant differences among populations were detected for each character. Estimates of repeatability of these traits were relatively high, suggesting substantial genotypic control over them. These estimates were consistent from population to population. Results of multivariate analyses suggest that populations from the Ottawa River region are similar to those from the St. Lawrence region, with populations from these regions diverging only in cone scale length. However, populations from the St. Lawrence region were more distinct from each other than those from the Ottawa River region. The population from Abitibi deviates considerably from the other populations, suggesting habitat-selection pressures acting at the margin of the natural range of the species under continental conditions. Finally, no general geographical trend was detected in the observed variation. Key words: white pine, morphology, cone, seed, variation.
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Doyon, Christian, Réjean Fortin, and Philip A. Spear. "Retinoic acid hydroxylation and teratogenesis in lake sturgeon (Acipenser fulvescens) from the St. Lawrence River and Abitibi region, Quebec." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 8 (August 1, 1999): 1428–36. http://dx.doi.org/10.1139/f99-086.
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All-trans-retinoic acid (RA) is an extremely active form of vitamin A; however, excessive or insufficient concentrations elicit anomalies including those associated with limb and craniofacial development. Lake sturgeon (Acipenser fulvescens) from the St. Lawrence River and tributaries were estimated to have a 2.9% incidence of fin and craniofacial malformations. Among larvae raised in artificial streams, a greater incidence of fin malformations (6.3%; p < 0.001) occurred in St. Lawrence River sturgeon compared with larvae from the Abitibi region. To test the hypothesis that the differences in rate of malformations may be associated with metabolic imbalances of RA, cytochrome P-450 dependent conversion to 4-hydroxyretinoic acid (4-OH-RA) was investigated. Optimal assay conditions are described for in vitro 4-OH-RA production in liver microsomes. Enzyme activity tended to decrease with increasing age and gonadal development in fish collected from Abitibi, but no statistically significant effects of sex, age, length, or gonadal development were discerned. The rate of 4-OH-RA formation was 3.5-fold greater (p < 0.0001) in the St. Lawrence sturgeon while the concentrations of cytochrome P-450 inducing PCBs (expressed as dioxin toxic equivalents) were 20-fold greater in a composite liver sample of the St. Lawrence sturgeon. Liver retinoid concentrations were negatively correlated (p < 0.0001) with RA hydroxylation rate. These results are consistent with the possibility that cytochrome P-450 dependent RA metabolism increased by chemical contaminants is associated with developmental anomalies in the St. Lawrence sturgeon.
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Lawrence, Bruce B. "The Cosmopolitan Canopy of East Maritime Southeast Asia: Minority citizenship in the Phil-Indo Archipelago." Comparative Islamic Studies 7, no. 1-2 (September 20, 2012): 67–104. http://dx.doi.org/10.1558/cis.v7i1-2.67.
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In this article Lawrence examines the elusive yet decisive role of the public square. He explains that the “public square” is the crucial category for understanding the scale and scope of citizenship. Both Indonesia and the Philippines resemble other contemporary polities in so far as their subjects/citizens project public faith, or religion in the public square. Minorities, like their majority neighbors, are ‘pious patriots,’ but they are patriots first. Lawrence demonstrates that to understand minority citizenship, individual voices from both polities must be analyzed. In doing so, he questions whether they can be simply categorized as full-fledged citizens of nation-states. Key terms that define minority relations are IP (Indigenous People) for the Southern Philippines, and adat (native practices) for many of the newly autonomous regions within Indonesia. By examining both IP and adat, Lawrence underscores the benefits, but also reveals the shortcomings, of the public square as it functions throughout the Phil-Indo Archipelago. This study concludes with a projection of what future changes in the public square will augur, not only for the region but also for its neighbors.
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Bruins, Hendrik J., and Johannes van der Plicht. "Radiocarbon Dating the “Wilderness of Zin”." Radiocarbon 49, no. 2 (2007): 481–97. http://dx.doi.org/10.1017/s0033822200042417.
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An important archaeological survey was conducted by Leonard Woolley and T E Lawrence in 1914 on behalf of the Palestine Exploration Fund in the Negev and northeastern Sinai deserts—the “Wilderness of Zin.” The region of Ain Kadeis, associated by some scholars in the 19th century with biblical Kadesh-Barnea, received much attention in their survey and discussions. Concerning the vexed question of Kadesh-Barnea, Woolley and Lawrence gave their preference for the nearby Ain el Qudeirat Valley, and in particular the ancient tell. Their survey contributed significantly in the shaping of scholarly opinion on the matter, even until today. But modern surveys and excavations failed to identify any archaeological remnants of the 2nd millennium BCE in the above regions, thereby putting the above associations in question. The Middle Bronze Age II, Late Bronze Age, and Iron Age I that cover this millennium are considered missing in the area in archaeological terms. However, our research reveals that archaeological remains of the 2nd millennium BCE do exist in the region, as determined chronologically by radiocarbon dating. A geoarchaeological approach is required to investigate terraced fields in wadis, which contain a unique record of human activity in these desert regions.
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Gagnon, François, Jacques Ibarzabal, Jean-Pierre L. Savard, Marc Bélisle, and Pierre Vaillancourt. "Autumnal patterns of nocturnal passerine migration in the St. Lawrence estuary region, Quebec, Canada: a weather radar study." Canadian Journal of Zoology 89, no. 1 (January 2011): 31–46. http://dx.doi.org/10.1139/z10-092.
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We documented the pattern of nocturnal passerine migration on each side of the St. Lawrence estuary (Côte-Nord north and Gaspésie south), using the Doppler Canadian weather surveillance radar of Val d’Irène (XAM). We examined whether autumnal migrants flew across the St. Lawrence, resulting in a uniform broad-front migration, or avoided crossing it, resulting in a bird concentration along the north coast. We found that a proportion of migrants crossed the estuary but that most followed the north coast. Ranges at which birds were detected were, on average, greater on Côte-Nord, thereby rejecting the uniform broad-front migration hypothesis, inasmuch as reflectivity measurements suggested that bird concentrated along Côte-Nord. The mean flight direction on Côte-Nord was southwest but shifted westward as the night progressed, avoiding crossing the estuary by late night. In Gaspésie, the mean flight direction over land was south and no directional shift was observed throughout the night. Flight altitude reach up to 1000 m above sea level (a.s.l.), but migratory activity was highest in the first 500 m a.s.l. It appears that the St. Lawrence estuary acts as a leading line and a barrier for nocturnal passerine migrants, and likely shapes migration farther south in Canada and in the United States.
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Notfors, Emma. "Heteroglossic itineraries and silent spaces: the desert cartographies of Gertrude Bell and TE Lawrence." cultural geographies 25, no. 4 (July 18, 2018): 589–601. http://dx.doi.org/10.1177/1474474018785989.
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This article advocates for the central importance of examining cartography for the understanding of literary travel narratives, focussing on accounts of travel in the deserts of the Middle East written by Gertrude Bell and TE Lawrence, both explorers, archaeologists and authors who were implicated in British activities in the Middle East before, during and after the Arab Revolt, and who travelled through the region during the early 20th century. This article seeks to explore the connections between the authors’ textual depictions and the maps that they authored, using close readings of their travel narratives and their maps to arrive at a more profound understanding of how these processes of authorship resulted in the production and mediation of ‘Arabia’ as an imaginative geography. Drawing on archival research and a range of textual sources, the development of this literary geography is traced through the early research of TE Lawrence on crusader castles in Syria and Lebanon, Gertrude Bell’s descriptions of using maps in The Desert and the Sown, Lawrence’s account of collating a map of Sinai for the War Office and the relationship between local navigational knowledges with their cartographic activities.
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TAYLOR, CHRISTOPHER K. "Notes on Phalangiidae (Arachnida: Opiliones) of southern Africa with description of new species and comments on within-species variation." Zootaxa 4272, no. 2 (May 29, 2017): 236. http://dx.doi.org/10.11646/zootaxa.4272.2.5.
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Notes are provided on a collection of Afrotropical harvestmen (Opiliones: Palpatores: Phalangiidae) from the California Academy of Sciences. A new species of Rhampsinitus, R. conjunctidens n. sp., is described from Limpopo province of South Africa. Rhampsinitus flavobrunneus Staręga 2009 and R. silvaticus Lawrence 1931 are recognised as junior synonyms of R. nubicolus Lawrence 1963 and R. vittatus Lawrence 1931, respectively. Both R. conjunctidens and R. nubicolus are recognised as exhibiting strong male dimorphism with major males exhibiting larger body size and greatly enlarged chelicerae relative to minor males; minor males cannot be readily identified to species without examination of genitalia. A discussion is also provided on generic boundaries within Afrotropical Phalangiidae, and a generic key to males of the region is presented.
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Harding, Gareth, Ellen Kenchington, and Zhensui Zheng. "Morphometrics of American Lobster (Homarus americanus) Larvae in Relation to Stock Determinations in the Maritimes, Canada." Canadian Journal of Fisheries and Aquatic Sciences 50, no. 1 (January 1, 1993): 43–52. http://dx.doi.org/10.1139/f93-005.
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Morphological characteristics of the first larval stage of the American lobster (Homarus americanus) enabled the separation of the Maritime population with stepwise discriminant function analysis into three groups: the southern Gulf of St. Lawrence and its outflow around Cape Breton Island, the Atlantic inshore region of Nova Scotia, and the offshore banks bordering the Gulf of Maine. Once the effect of environmental temperature on larval size was removed, the differences between Georges and Browns banks and the Atlantic inshore disappeared. The remaining differences, chiefly in the dimensions of the second and fifth abdominal segments and the rostrum, between larvae from the Cape Breton sites and elsewhere may be due to other environmental factors or partial genetic isolation. Conservation and management practices over the past century have increased gene flow between regions, and most of this appears to be from the release of Gulf of St. Lawrence lobsters in the Gulf of Maine. A reassessment of previous studies on adult morphology, benthic movements, larval dispersal, enzyme electrophoresis, and commercial landing patterns supports the separation of the Gulf of St. Lawrence stock from the rest of the Canadian Maritimes.
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Elson, John A. "West-southwest glacial dispersal of pillow-lava boulders, Philipsburg–Sutton region, Eastern Townships, Quebec." Canadian Journal of Earth Sciences 24, no. 5 (May 1, 1987): 985–91. http://dx.doi.org/10.1139/e87-095.
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Pillow-lava boulders, probably from Place Mountain in the Bolton valley east of the Sutton Mountains, occur in a narrow belt or fan 43 km long trending west-southwest (azimuth about 248°) from 10 km southwest of Place Mountains to Rosenberg, near Philipsburg, Quebec. Glacial striations with this direction are uncommon; the general glacial movement indicated by abundant striations and indicator erratics is southeastward. A southwestward flow in the axial part of the St. Lawrence Lowlands near Montréal is apparently the youngest direction there, of late Wisconsinan age. In the Eastern Townships of Quebec east and northeast of the study area and in adjoining northern Vermont there is evidence of a southwestward flow of mid-Wisconsinan age. Local southwestward flow in the study area at the beginning and end of a glacial cycle may have resulted from a mobile bed in the flooded St. Lawrence – Champlain lowland, but a hypothesis of flow from a major mid-Wisconsinan axis of accumulation in the northern Appalachians farther to the east is supported by much published field evidence.
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Plourde, Stéphane, Pierre Joly, Jeffrey A. Runge, Bruno Zakardjian, and Julian J. Dodson. "Life cycle of Calanus finmarchicus in the lower St. Lawrence Estuary: the imprint of circulation and late timing of the spring phytoplankton bloom." Canadian Journal of Fisheries and Aquatic Sciences 58, no. 4 (April 1, 2001): 647–58. http://dx.doi.org/10.1139/f01-006.
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The life cycle of Calanus finmarchicus in the lower St. Lawrence estuary is described based on observations of female egg production rate, population stage abundance, and chlorophyll a biomass collected over 7 years (19911997) at a centrally located monitoring station. The mean seasonal pattern shows maximum abundance of females in May, but peak population egg production rate and naupliar (N3N6) abundance occur in early July just after onset of the late spring early summer phytoplankton bloom. The population stage structure is characterized by low summer abundance of early copepodite stages C1C3 and high stage C5 abundance in autumn. Between 1994 and 1997, there was important interannual variation in both timing (up to 1 month) and amplitude (five- to eight-fold) of population reproduction. Patterns of seasonal increase of C5 abundance in autumn suggest interannual variations of both timing and magnitude of deep upstream advection of this overwintering stage. Thus, the main features of C. finmarchicus population dynamics in the central lower St. Lawrence Estuary are (i) late reproduction resulting from food limitation prior to the onset of the summer phytoplankton bloom, (ii) probable export of early developmental stages during summer, and (iii) advection into the central lower St. Lawrence Estuary of overwintering stage C5 in autumn from downstream regions. These results support the hypothesis that circulation, mainly driven by discharge from the St. Lawrence River and its tributaries, is a key factor governing population dynamics of C. finmarchicus in this region.
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Tremblay, G., and J. M. Beausoleil. "Réponse du soya à la fertilisation minérale en éléments majeurs NPK sur des sols classés de riches à excessivement riches en phosphore ou en potassium des Basses Terres du Saint-Laurent." Canadian Journal of Plant Science 80, no. 2 (April 1, 2000): 261–70. http://dx.doi.org/10.4141/p99-075.
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In the scientific literature there are numerous studies on soybean response to major mineral NPK elements. But there are few research data on this topic for the Lowland soils of the Saint-Lawrence Valley. A 3-yr study was conducted in 1994, 1995, and 1996 on three representative soil types of the lowland Saint-Lawrence Valley region: Dujour, Sainte-Rosalie and Saint-Urbain. These soils are classified from rich to excessively rich in available phosphorus and potassium as measured by the Mehlich 3 method. Results of this study indicate that yield is rarely significantly influenced by levels of nitrogen, phosphorus or potassium fertilization. Moreover, there are no significant interactions among those elements and soybean grain yield. Other observed variables (specific weight, grain visual quality, 100-seed weight, seed protein and oil contents) were generally not affected by the different levels of nitrogen, phosphorus or potassium fertilization. There were few significant interactions between major elements and those variables. Generally, soybeans did not respond to NPK mineral fertilization on representative soils of the Lowland Saint Lawrence Valley region classified from rich to excessively rich in available phosphorus and potassium. Key words: Soybean, fertilization, nitrogen, phosphorus, potassium, yield
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Belland, René J. "Floristic boundaries in the Gulf of St. Lawrence region: a numerical approach based on the moss flora." Canadian Journal of Botany 67, no. 6 (June 1, 1989): 1633–44. http://dx.doi.org/10.1139/b89-206.
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Possible phytogeographic boundaries within the Gulf of St. Lawrence region are examined using the moss floras of 29 smaller geographic units. Principal coordinates analysis (PCoA) shows floristic change in the Gulf to be gradual and to follow two major gradients, a north–south gradient and an east–west gradient. These are positively correlated to the distributions of temperate and arctic species, respectively. PCoA ordinations also show no evidence of distinct boundaries between adjacent units, but indicate that Cape Breton Island and Gaspé Peninsula have floras of intermediate composition to those of the Maritimes and Newfoundland. Randomly generating floras for adjacent units using Monte Carlo simulation supports the results obtained from PCoA. The real Jaccard similarities between adjacent units are found to be greater than those expected from simulation. The lack of distinct boundaries in the Gulf of St. Lawrence region is attributed to the high diversity of species distributions possible in a region with complex environmental gradients.
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Belland, René J. "A multivariate study of moss distributions in relation to environment in the Gulf of St. Lawrence region, Canada." Canadian Journal of Botany 83, no. 3 (March 1, 2005): 243–63. http://dx.doi.org/10.1139/b04-172.
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Moss distribution patterns in the Gulf of St. Lawrence were investigated using multivariate analyses to determine the relationship of the patterns to environmental factors. Distance-based redundancy analysis was used to ordinate 29 operational geographical units (OGU) or sampling units based on their moss floras, and hierarchical cluster analysis in combination with indicator analysis was used to produce classifications of both species and sampling units. Climatic variables, in particular, warmth of the growing season, were the most important factors determining species distribution; this resulted in a northsouth gradient through the study area. Oceanity was also shown to be important and manifested as an eastwest gradient. Edaphic factors, in particular, amount of calcareous rock outcrop, had a secondary influence and modified the patterns established by climate. Ordination of OGUs showed the effects of environment to be more variable in the northern half of the Gulf of St. Lawrence, which may in part explain the higher species richness there. Seven OGU groups were recognized based on cluster analysis of floristic composition. Although indicator species were few, most groups were distinguished by unique sets of regionally rare species. Eleven species elements were identified based on species occurrence in OGUs. The elements constituted sets of overlapping distributions showing southern, northern, and eastern biases in the Gulf region. Multivariate analysis was shown to be effective tool for extracting mossenvironment patterns, even at medium geographic scale.Key words: Gulf of St. Lawrence, mosses, environment, richness, distribution, ordination, cluster analysis.
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Harvey-Clark, Chris J., Jeffrey J. Gallant, and John H. Batt. "Vision and its Relationship to Novel Behaviour in St. Lawrence River Greenland Sharks, Somniosus microcephalus." Canadian Field-Naturalist 119, no. 3 (July 1, 2005): 355. http://dx.doi.org/10.22621/cfn.v119i3.145.
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Rarely observed Greenland Sharks, Somniosus microcephalus, were recorded at shallow depths by divers employing underwater video in the St. Lawrence River, in association with a seasonal concentration of Capelin (Mallotus villosus) in May-June 2003. We recorded unique proximity-induced display motor patterns in these sharks, which have not been recorded in underwater observations of Arctic Greenland Sharks. Arctic sharks have a high incidence of blindness due to an ocular copepod parasite, Ommatokoita elongata. The absence of parasite-induced blindness in St. Lawrence Greenland Sharks, in contrast to endemic blindness in the Arctic population, may allow sharks in this region to more readily visually recognize the presence of conspecifics and potential prey. Improved visual acuity may therefore allow St. Lawrence River sharks to express a different behavioural repertoire than Arctic sharks, with resulting changes in intra- and inter-specific aggression and predatory behaviour.
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Dreimanis, A. "Correlation of Wisconsin glacial events between the Eastern Great Lakes and the St. Lawrence Lowlands." Cadre stratigraphique et paléoclimatique 31, no. 1-2 (December 9, 2010): 37–51. http://dx.doi.org/10.7202/1000053ar.
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The interrelationship of the Wisconsin glaciogenic events among the Upper St. Lawrence Lowland and the eastern Great Lakes, particularly the Lake Ontario basin is controlled mainly by 3 factors: 1) presence or absence of a glacial dam across the St. Lawrence Lowland; 2) isostatic lowering or rise of the outlet of Lake Ontario, related mainly to glacial loading or unloading in the Upper St. Lawrence Lowland; 3) shifting in the regional direction of glacial movement through the Upper St. Lawrence Lowland, upglacier from it, and in the Lake Ontario basin. Changes in the above conditions result in detectable changes in lake levels, and in compositional changes of tills in the Lake Ontario basin. Crosschecking of the above relationships supports the relative sequence already proposed. However, the chronology of the events which are older than reliable finite 14C dates, may be reinterpreted by a comparison with oceanic stratigraphies. A possible re-interpretation of some late-glacial Late Wisconsin glacial fluctuations depends greatly upon the reliability of 14C dates on shells and correct interpretation of till-like deposits. For those glacial fluctuations in the St. Lawrence Lowlands which lack 14C dates, it is tempting to apply correlations with the 14C dated stratigraphie units of the Great Lakes Region, but we have to consider also possible regional differences in glacial dynamics.
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Gyakum, John R. "The Application of Fred Sanders' Teaching to Current Research on Extreme Cold-Season Precipitation Events in the Saint Lawrence River Valley Region." Meteorological Monographs 55 (November 1, 2008): 241–50. http://dx.doi.org/10.1175/0065-9401-33.55.241.
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Abstract Fred Sanders' teaching and research contributions in the area of quasigeostrophic theory are highlighted in this paper. The application of these contributions is made to the topic of extreme cold-season precipitation events in the Saint Lawrence valley in the northeastern United States and southern Quebec. This research focuses on analyses of Saint Lawrence valley heavy precipitation events. Synoptic- and planetary-scale circulation anomaly precursors are typically identified several days prior to these events. These precursors include transient upper-level troughs, strong moisture transports into the region, and anomalously large precipitable water amounts. The physical insight of Fred Sanders' work is used in the analysis of these composite results. Further details of this insight are provided in analyses of one case of heavy precipitation.
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Caners, Richard T. "Fabronia ciliaris, a Moss New to Canada from Southeastern Manitoba." Canadian Field-Naturalist 131, no. 3 (February 28, 2018): 246–51. http://dx.doi.org/10.22621/cfn.v131i3.1961.
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Fabronia ciliaris (Fabroniaceae, Bryophyta) was recently discovered in the Great Lakes–St. Lawrence forest region in southeastern Manitoba. This collection represents the first record of the species in Canada and the northernmost extent of the species in North America.
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Mucci, Alfonso, Maurice Levasseur, Yves Gratton, Chloé Martias, Michael Scarratt, Denis Gilbert, Jean-Éric Tremblay, Gustavo Ferreyra, and Bruno Lansard. "Tidally induced variations of pH at the head of the Laurentian Channel." Canadian Journal of Fisheries and Aquatic Sciences 75, no. 7 (July 2018): 1128–41. http://dx.doi.org/10.1139/cjfas-2017-0007.
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The head of the Laurentian Channel is a very dynamic region of exceptional biological richness. To evaluate the impact of freshwater discharge, tidal mixing, and biological activity on the pH of surface waters in this region, a suite of physical and chemical variables was measured throughout the water column over two tidal cycles. The relative contributions to the water column of the four source-water types that converge in this region were evaluated using an optimum multiparameter algorithm (OMP). Results of the OMP analysis were used to reconstruct the water column properties assuming conservative mixing, and the difference between the model properties and field measurements served to identify factors that control the pH of the surface waters. These surface waters are generally undersaturated with respect to aragonite, mostly due to the intrusion of waters from the Upper St. Lawrence Estuary and the Saguenay Fjord. The presence of a cold intermediate layer impedes the upwelling of the deeper, hypoxic, lower pH and aragonite-undersaturated waters of the Lower St. Lawrence Estuary to depths shallower than 50 m.
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Magnan, Gabriel, Michelle Garneau, and Serge Payette. "Holocene development of maritime ombrotrophic peatlands of the St. Lawrence North Shore in eastern Canada." Quaternary Research 82, no. 1 (July 2014): 96–106. http://dx.doi.org/10.1016/j.yqres.2014.04.016.
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AbstractMacrofossil analyses were used to reconstruct long-term vegetation successions within ombrotrophic peatlands (bogs) from the northern shorelines of the St. Lawrence Estuary (Baie-Comeau) and the Gulf of St. Lawrence (Havre-St-Pierre). Over the Holocene, the timing and the ecological context of peatland inception were similar in both regions and were mainly influenced by fluctuations in relative sea level. Peat accumulation started over deltaic sands after the withdrawal of the Goldthwait Sea from 7500 cal yr BP and above silt–clay deposits left by the Laurentian marine transgression after 4200 cal yr BP. In each region, the early vegetation communities were similar within these two edaphic contexts where poor fens with Cyperaceae and eastern larch (Larix laricina) established after land emergence. The rapid transitions to ombrotrophy in the peatlands of Baie-Comeau are associated with particularly high rates of peat accumulation during the early developmental stage. The results suggest that climate was more propitious to Sphagnum growth after land emergence in the Baie-Comeau area. Macrofossil data show that treeless Sphagnum-dominated bogs have persisted over millennia and that fires had few impacts on the vegetation dynamics. This study provides insight into peatland vegetation responses to climate in a poorly documented region of northeastern America.
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Rutherford, Krysten, and Katja Fennel. "Diagnosing transit times on the northwestern North Atlantic continental shelf." Ocean Science 14, no. 5 (October 12, 2018): 1207–21. http://dx.doi.org/10.5194/os-14-1207-2018.
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Abstract. The circulation in the northwestern North Atlantic Ocean is highly complex, characterized by the confluence of two major western boundary current systems and several shelf currents. Here we present the first comprehensive analysis of transport paths and timescales for the northwestern North Atlantic shelf, which is useful for estimating ventilation rates, describing circulation and mixing, characterizing the composition of water masses with respect to different source regions, and elucidating rates and patterns of biogeochemical processing, species dispersal, and genetic connectivity. Our analysis uses dye and age tracers within a high-resolution circulation model of the region, divided into nine subregions, to diagnose retention times, transport pathways, and transit times. Retention times are shortest on the Scotian Shelf (∼ 3 months), where the inshore and shelf-break branches of the coastal current system result in high along-shelf transport to the southwest, and on the Grand Banks (∼ 3 months). Larger retention times are simulated in the Gulf of St. Lawrence (∼ 12 months) and the Gulf of Maine (∼ 6 months). Source water analysis shows that Scotian Shelf water is primarily comprised of waters from the Grand Banks and Gulf of St. Lawrence, with varying composition across the shelf. Contributions from the Gulf of St. Lawrence are larger at near-shore locations, whereas locations near the shelf break have larger contributions from the Grand Banks and slope waters. Waters from the deep slope have little connectivity with the shelf, because the shelf-break current inhibits transport across the shelf break. Grand Banks and Gulf of St. Lawrence waters are therefore dominant controls on biogeochemical properties, and on setting and sustaining planktonic communities on the Scotian Shelf.
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Lefèvre, Marylise A., Michael J. W. Stokesbury, Frederick G. Whoriskey, and Michael J. Dadswell. "Atlantic salmon post-smolt migration routes in the Gulf of St. Lawrence." ICES Journal of Marine Science 69, no. 6 (July 1, 2012): 981–90. http://dx.doi.org/10.1093/icesjms/fss092.
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Abstract Lefèvre, M. A., Stokesbury, M. J. W., Whoriskey, F. G., and Dadswell, M. J. 2012. Atlantic salmon post-smolt migration routes in the Gulf of St. Lawrence – ICES Journal of Marine Science, 69: 981–990. The migration of Atlantic salmon (Salmo salar) post-smolts from the Rivière Saint-Jean on the north shore of the Gulf of St. Lawrence (Canada) was studied during 2009 and 2010. Salmon from rivers in this region spend ≥2 years at sea before returning to spawn, and are believed to migrate to ocean feeding areas off Greenland. To determine residency time in the nearshore environment, and to define the migration routes of post-smolts, tagged post-smolts were tracked passively in Jacques Cartier Strait and at the two exits of the Gulf of St. Lawrence to the Atlantic Ocean (Cabot Strait and the Strait of Belle Isle). Post-smolts moved rapidly south in the nearshore area; two of them were detected 45 km south of the estuary exit, suggesting that they were moving towards the centre of the Gulf of St. Lawrence. One tagged post-smolt was detected exiting the Gulf of St. Lawrence via the Strait of Belle Isle after 44 d and exhibited a minimum swimming speed of 14.4 km d−1. There was no apparent linkage between the detection patterns of post-smolts and surface water temperatures or surface water currents close to shore. Post-smolts, however, appeared to orient to higher salinity.
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Payette, Serge, Vanessa Pilon, Pierre-Luc Couillard, and Jason Laflamme. "Fire History of Appalachian Forests of the Lower St-Lawrence Region (Southern Quebec)." Forests 8, no. 4 (April 11, 2017): 120. http://dx.doi.org/10.3390/f8040120.
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Spencer, Douglas R., and Patrick L. Hudson. "The Oligochaeta (Annelida, Clitellata) of the St. Lawrence Great Lakes Region: an Update." Journal of Great Lakes Research 29, no. 1 (January 2003): 89–104. http://dx.doi.org/10.1016/s0380-1330(03)70418-3.
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DesRosiers, Annie, Patrick Dolcé, Philippe Jutras, and Louise P. Jetté. "Susceptibility of Group A Beta-Hemolytic Streptococci in the Lower St Lawrence Region, Quebec." Canadian Journal of Infectious Diseases 10, no. 4 (1999): 279–85. http://dx.doi.org/10.1155/1999/212549.
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OBJECTIVE: To determine the susceptibility of group A beta-hemolytic streptococci (GABHS) in the lower St Lawrence region, Quebec to different antibiotics, particularly macrolides, and to compare different antibiogram methods (disk diffusion, E-test and microdilution) and incubation atmospheres (ambient air and 5% carbon dioxide).METHODS: A total of 384 strains of GABHS isolated from 377 patients (throat 335; other sites 49) from three hospitals in the lower St Lawrence region were analyzed for their susceptibility to erythromycin, clarithromycin, azithromycin, penicillin, clindamycin, cephalothin, rifampin and vancomycin by disk diffusion on Mueller-Hinton (MH) agar supplemented with 5% defibrinated sheep blood (MHB) at 35ºC in 5% carbon dioxide. Strains that were found to be intermediately resistant or resistant to one of the antibiotics by disc diffusion, strains from sites other than throat, and a sample of 97 pharyngeal strains were evaluated by E-test on MHB (35ºC, 5% carbon dioxide) for their susceptibility to the antibiotics erythromycin, clarithromycin, azithromycin, penicillin, clindamycin and ceftriaxone. In addition, minimum inhibitory concentrations (MICs) were determined for erythromycin and azithromycin by broth microdilution using MH broth supplemented with 2.5 % of lysed horse blood (35ºC, ambient air) on strains that were resistant or intermediately resistant to the macrolides (erythromycin, clarithromycin, azithromycin). An evaluation was also carried out on these strains to determine the influence of the incubating atmosphere (ambient air versus 5% carbon dioxide) on susceptibility results obtained by disk diffusion (erythromycin, clarithromycin and azithromycin) and E-test (erythromycin and azithromycin) methods.RESULTS: Nine strains (2%) from nine patients (throat eight, pus one) were resistant to all macrolides as tested by three different techniques (disk diffusion, E-test and microdilution). All strains were susceptible to all the other antibiotics tested. For the strains intermediately resistant or resistant to macrolides, incubation in a 5% carbon dioxide atmosphere was associated with a reduction in the diameter of inhibition determined by disk diffusion (P<0.001) with frequent minor variations in interpretation, and with an increase in the MIC by E-test (P<0.001), which had no impact on interpretation.CONCLUSIONS: Resistance of GABHS to macrolides was not common (2%) in the lower St Lawrence Region. GABHS susceptibility to erythromycin seemed to predict the susceptibility to the other macrolides. Significant variation in antibiogram results (disk diffusion and E-test) of GABHS susceptibility to macrolides was related to the incubation atmosphere and may have an impact on the interpretation of disk diffusion results.
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MILLER, JOHN E. "Lawrence Welk and John Wooden: Midwestern Small-Town Boys Who Never Left Home." Journal of American Studies 38, no. 1 (April 2004): 109–25. http://dx.doi.org/10.1017/s0021875804007923.
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Considered by many to be the most American part of America, the Midwest occupies a unique place in the national psyche, and its residents have been called the archetypal or quintessential Americans. The region is – and was – anything but homogenous, and any adequate treatment of it needs to take into account its many variations, complexities, and paradoxes. Any search for the essential character of the region soon founders on recognition of its cultural diversity. Yet, acknowledgment of the hazards of advancing broad generalizations about a region extending from Ohio to the Dakotas and ranging as far south as Missouri should not bar us from inquiring into the qualities and characteristics of its people. Despite the contradictions and complexities attaching to the region, the Midwest possesses a distinctive cultural identity, joining its constituent elements in an unstable and constantly changing, but nevertheless recognizable, pattern.
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Belland, René J., and Marc Favreau. "The moss flora of the Gaspé Peninsula (Quebec, Canada): list of species and preliminary analysis." Canadian Journal of Botany 66, no. 9 (September 1, 1988): 1780–99. http://dx.doi.org/10.1139/b88-244.
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Extensive field studies and evaluation of previously published reports reveal a moss flora of at least 310 species for the Gaspé Peninsula. Forty species are reported for the first time from the peninsula, and Brachythecium glaciale is new to Quebec. While the Gaspé flora cannot be considered a distinctive one within the Gulf of St. Lawrence region, the large number of rare species is significant. Their presence in the Gaspé can be attributed to the diverse geology and topography of the peninsula. The bulk of the moss flora is clearly of boreal affinity, but many species have temperate, montane, or arctic – alpine distributions. Of special interest is the large proportion of species with various types of disjunct distributions, either within eastern North America or to other parts of the world, especially western North America. Some patterns strongly support the idea of survival in refugia in the Gulf of St. Lawrence region during the last glaciation.
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Kawasaki, K., and D. T. A. Symons. "Paleomagnetism of fluorite veins in the Devonian St. Lawrence granite, Newfoundland, Canada." Canadian Journal of Earth Sciences 45, no. 9 (September 2008): 969–80. http://dx.doi.org/10.1139/e08-045.
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Paleomagnetic results are reported from the Devonian St. Lawrence granite and the fluorite veins within the granite or its related porphyry dikes. Paleomagnetic analysis of 359 specimens from 29 sites shows that there is no statistically significant difference at 95% confidence between the site mean characteristic remanent magnetization (ChRM) directions carried by pyrrhotite and (or) magnetite of the granite and fluorite veins. No post-granite metamorphic event is known in the area. Thus, these concordant directions indicate that the granite and fluorite veins are coeval and retain a primary remanence. However, the mean ChRM direction of 25 vein and granite sites yields an Early Pennsylvanian paleopole of ∼316 Ma on the North American apparent polar wander path at 35.5°N, 129.2°E (A95 = 3.4°) that is younger than the 374 ± 2 Ma Devonian U–Pb zircon age for the granite. Two intersecting vertical vein sets indicate that the St. Lawrence granite has not been tilted since emplacement of the fluorite veins. Therefore, the difference between the measured and expected paleopoles is interpreted to result from a postemplacement counterclockwise rotation of ∼17° of the St. Lawrence granite region about a vertical axis. Analysis of Carboniferous paleopoles in the northern Appalachian orogen indicates the rotation at the St. Lawrence area is Late Devonian during the Acadian orogeny.
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Goudarzi, Mohammad Ali, Marc Cocard, and Rock Santerre. "ESTIMATING EULER POLE PARAMETERS FOR EASTERN CANADA USING GPS VELOCITIES." Geodesy and Cartography 41, no. 4 (December 17, 2015): 162–73. http://dx.doi.org/10.3846/20296991.2015.1123445.
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Eastern Canada is characterized by many intraplate earthquakes mostly concentrated along the Saint Lawrence River and Ottawa River valleys. After the rigid plate rotation of North America, the glacial isostatic adjustment (GIA) is by far the largest source of geophysical signal in eastern Canada. We estimate a set of Euler pole parameters for this area using a velocity field of 19 continuously operating GPS stations out of 112, and show that they are different from the overall rotation of the North American plate. This difference potentially reflects local stresses in this seismic region, and the difference in intraplate velocities between the two flanks of the Saint Lawrence River valley accumulate stress along the river.
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Aubry, Eliane, D. A. Methven, and Tom Hurlbut. "Length–depth relations of Enchelyopus cimbrius fourbeard rockling (Gadiformes: Phycidae) from the southern Gulf of St Lawrence and Cabot Strait in relation to abiotic factors." Journal of the Marine Biological Association of the United Kingdom 89, no. 8 (August 5, 2009): 1643–53. http://dx.doi.org/10.1017/s0025315409000800.
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Research vessel survey data collected by Fisheries and Oceans Canada in the southern Gulf of St Lawrence (1971–2002) and Cabot Strait (1994–1997) were analysed to determine if Enchelyopus cimbrius the fourbeard rockling, distributed itself with larger individuals occurring in deeper water. A positive size–depth relationship was first observed for the European plaice, Pleuronectes platessa in the North Sea and has been reported for other fish. Positive relationships were found between the total length of E. cimbrius and depths where it occurred in this study. However, the biological relationship was not significant since the linear regression slopes were very weak, explaining less than approximately five per cent of the variance observed. Data were analysed further to determine the water depth, temperature and salinity ranges where the fourbeard rockling was most abundant. Enchelyopus cimbrius occurred throughout the depth-ranges sampled with highest catches occurring at 25–50 m (southern Gulf of St Lawrence) and deeper than 200 m (southern Gulf of St Lawrence and Cabot Strait). Low catches at intermediate depths (~50–100 m) in the southern Gulf of St Lawrence may have been due to the lack of suitable mud substrate and colder bottom temperatures in the Magdalen Shallows, a large central region of the southern Gulf. Enchelyopus cimbrius was mostly caught at relatively narrow temperature and salinity ranges of 4–6°C and 34–34.9 ppt in both regions, and only occurred in areas with a mud substratum, predominantly in the eastern Northumberland Strait, Baie des Chaleurs and in the deeper water of the Cape Breton Trough, Laurentian Channel and Cabot Strait. Enchelyopus cimbrius was caught throughout the day and night, contradicting a previous study that characterized it as being nocturnal in shallow coastal waters off Newfoundland.
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Blasco, Dolors, Maurice Levasseur, Esther Bonneau, Roger Gelinas, and T. T. Packard. "Patterns of paralytic shellfish toxicity in the St. Lawrence region in relationship with the abundance and distribution of Alexandrium tamarense." Scientia Marina 67, no. 3 (September 30, 2003): 261–78. http://dx.doi.org/10.3989/scimar.2003.67n3261.
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Laforest, Sonia, Vincent Martin, and Michel Boulé. "QUEBEC REGION'S SHORELINE SEGMENTATION IN THE ST. LAWRENCE RIVER: RESPONSE TOOL FOR OIL SPILL." International Oil Spill Conference Proceedings 2005, no. 1 (May 1, 2005): 317–20. http://dx.doi.org/10.7901/2169-3358-2005-1-317.
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ABSTRACT The Quebec Region's shoreline description of the St. Lawrence River began in 1985 with the first shoreline interpretation by Environment Canada. This description was available as a paper version and was no longer adequate for oil spill response. An update was required in order to split the shoreline into segments and to digitize the information. A partnership was developed between Environment Canada, Eastern Canada Response Corporation and the Canadian Coast Guard to conduct the aerial survey and to do the segmentation. The cartography of segmentation covers the fluvial part of the St. Lawrence River (Montreal Region) up to the Gulf (including the Lower-North Shore and the St. Lawrence Islands). The database, developed specifically for that project, is oil spill-oriented. It includes geomorphologic information, from the supratidal to the lower intertidal zone, some statistical information and other requirements for the cleanup operation. For this operational database, useful for the response operation, links were developed with other databases and specialized oil spill software. The first system is GENIE Web, which is a Georeference Environmental Network for Information Exchange on the Web. The second system, ShoreAssess©, is a managing tool for SCAT teams in the field. Finally, a partnership with the Geography Department at the Université du Québec in Rimouski (UQAR) will help us to keep the St. Lawrence River coastal evolution up to date.
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Cordeiro, Danilo Pacheco. "First record to Brazil of one genera and seven species of Psychodidae (Diptera) with further new records for 10 countries on the Neotropics." Papéis Avulsos de Zoologia 60 (January 31, 2020): e20206002. http://dx.doi.org/10.11606/1807-0205/2020.60.02.
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With a big territory and variety of biomes, Brazil is one of the most diverse countries in the World, with insects massively contributing to this diversity. Although presenting impressive numbers, many groups are poorly known concerning their diversity and distribution. Also, the knowledge of the species diversity is very heterogeneous when comparing Brazilian states and regions. With a recent review of part of Lawrence Quate’s collection deposited at Natural History Museum of Los Angeles County, more than 70 new geographical records for Psychodidae species were found on the Neotropics, including one genera (Eurygarka) and seven species first recorded to Brazil. The complete known distribution of these species was compiled and is presented along with new records for other 11 countries of the Neotropical region. On the Brazilian territory, most of the new records are for the state of Rondônia, on the northern region, followed by Minas Gerais, on the southeastern region.
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Labbé, Myriam, Frédéric Raymond, Alice Lévesque, Mary Thaler, Vani Mohit, Martyne Audet, Jacques Corbeil, and Alexander Culley. "Communities of Phytoplankton Viruses across the Transition Zone of the St. Lawrence Estuary." Viruses 10, no. 12 (November 27, 2018): 672. http://dx.doi.org/10.3390/v10120672.
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The St. Lawrence hydrographic system includes freshwater, brackish, and marine habitats, and is the largest waterway in North America by volume. The food-webs in these habitats are ultimately dependent on phytoplankton. Viral lysis is believed to be responsible for a major part of phytoplankton mortality. To better understand their role, we characterized the diversity and distribution of two viral taxa infecting phytoplankton: the picornaviruses and phycodnaviruses. Our study focused on the estuary transition zone, which is an important nursery for invertebrates and fishes. Both viral taxa were investigated by PCR amplification of conserved molecular markers and next-generation sequencing at six sites, ranging from freshwater to marine. Our results revealed few shared viral phylotypes between saltwater and freshwater sites. Salinity appeared to be the primary determinant of viral community composition. Moreover, our analysis indicated that the viruses identified in this region of the St. Lawrence diverge from classified viruses and homologous published environmental virotypes. These results suggest that DNA and RNA viruses infecting phytoplankton are likely active in the estuary transition zone, and that this region harbors its own unique viral assemblages.
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Belland, René J., W. B. Schofield, and Terry A. Hedderson. "Bryophytes of Mingan Archipelago National Park Reserve, Quebec: a boreal flora with arctic and alpine components." Canadian Journal of Botany 70, no. 11 (November 1, 1992): 2207–22. http://dx.doi.org/10.1139/b92-274.
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The Mingan Archipelago National Park Reserve has a bryophyte flora of 302 species, including 233 mosses and 69 hepatics. This includes about 45% of the known bryoflora of the Gulf of St. Lawrence region. The park bryophyte flora is dominated by boreal species and has lesser representation of temperate and arctic-alpine species. About 73% of the park flora belongs to the boreal distributional element and two-thirds of these species are circumboreal or widespread in the boreal biome of the northern hemisphere. The flora is youthful and all species have colonized the islands within the last 7000 years. Most of the Mingan species probably originated from populations that survived during the last glaciation in sites south of the icesheet margin. However, many species could have migrated to the islands from nearby réfugia within the Gulf of St. Lawrence region where they were able to survive the glaciation in situ. These refugial species include many of the arctic-alpine and montane species found in the park. Key words: Mingan Islands, bryophytes, diversity, glaciation.
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Roy, Gilles. "Une épidémie d’insectes, facteur de déboisement dans le Québec." Cahiers de géographie du Québec 2, no. 4 (April 12, 2005): 233–40. http://dx.doi.org/10.7202/020090ar.
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Spruce budworm bas invaded the forest of Québec since 1939, especially the pines of the coniferous area. There are jour major infested regions : three are located on the North shore of the St. Lawrence river : in the Gatineau river bassin, in the Laurentians between the Lachute Area and lake St. John, and in the North Shore region behind Baie Comeau Sept-Iles. The fourth region starts behind Rimouski and spreads eastward, covering the whole Gaspé peninsula. In this last the authorities are quite concerned about this plague, which is becoming a serious menace to the forest industries. Various air-spays have been used during the past jour years in order to circumscribe the dammages, and more than 4,000,000 acres have been treated with DDT, first step toward the rehabilitation of the forest.
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Parent, Michel, and Serge Occhietti. "Late Wisconsinan deglaciation and glacial lake development in the Appalachians of southeastern Québec." Géographie physique et Quaternaire 53, no. 1 (October 2, 2002): 117–35. http://dx.doi.org/10.7202/004859ar.
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Abstract Late Wisconsinan deglaciation in southeastern Québec was preceded by a northward ice-flow reversal that was recorded in the northeastern part of the region. The reversal event was generated by flow convergence toward the St. Lawrence Ice Stream, a northeastward-flowing ice stream which formed in the St. Lawrence estuary prior to 13 000 years BP and lasted until at least 12 400 years BP. In the Bois-Francs uplands, the flow reversal event led to the formation of a semi-detached ice mass that underwent widespread stagnation and downwasting. In the southwestern region, northward retreat of the margin of the Laurentide Ice Sheet was marked by the formation of a series of discontinuous recessional moraines and by the development of ice-dammed lakes in the main valleys. The level of these lakes fell as progressively lower outlets became ice-free. The main episodes are (1) the Sherbrooke Phase of Glacial Lake Memphremagog, (2) an unnamed transitional lake and (3) Glacial Lake Candona, a large lake which had expanded northeastward from the deglaciated regions of the Upper St. Lawrence (Lake Iroquois) and Ottawa valleys to the Lake Champlain (Glacial Lake Vermont) basin. As recorded by the Danville Varves, Lake Candona lasted about 100 years following deposition of the Ulverton-Tingwick Moraine. Subsequent ice retreat along the Appalachian piedmont led to final drainage of Lake Candona and allowed Champlain Sea waters to invade much of these glaciolacustrine terrains about 12 000 years BP. On the basis of the Danville Varves record, a regional rate of ice retreat of about 200 m·a -1 is inferred. The age of the earliest moraine, the Frontier Moraine, is thus about 12 550 years BP, while the ages of the subsequent Dixville, Cherry River-East-Angus, Mont Ham and Ulverton-Tingwick moraines are estimated at 12 500, 12 325, 12 200 et 12 100 years BP, respectively.
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Taillefer, François. "La morphologie des environs de Québec et la basse-vallée du Saint-Laurent." Cahiers de géographie du Québec 2, no. 4 (April 12, 2005): 177–91. http://dx.doi.org/10.7202/020087ar.
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The morphology of the Québec region and the lower St. Lawrence valley is reappraised in this article divided in three parts. The physical landscape is described in part I ; the structural conditions are examined in part II and the morphological problems are presented in part III. The relief is the result of a succession of glacial episodes and submersion and emersion episodes which followed glaciation. The over deepening of the Limoilou depression and the opening of Calvaire lake and Cap Rouge depressions are the results of the glacier. To the submerged phase correspond the alluvial fill, especially thick in the Limoilou depression, and during the emersion phase, the St. Lawrence cut in soft schists the Ancienne Lorette and the lower terrace which would have been shaped after the over deepening of the Limoilou depression.
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Hart, John P., William A. Lovis, and M. Anne Katzenberg. "Early Maize in Northeastern North America: A Comment on Emerson and Colleagues." American Antiquity 86, no. 2 (April 2021): 425–27. http://dx.doi.org/10.1017/aaq.2020.93.
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Emerson and colleagues (2020) provide new isotopic evidence on directly dated human bone from the Greater Cahokia region. They conclude that maize was not adopted in the region prior to AD 900. Placing this result within the larger context of maize histories in northeastern North America, they suggest that evidence from the lower Great Lakes and St. Lawrence River valley for earlier maize is “enigmatic” and “perplexing.” Here, we review that evidence, accumulated over the course of several decades, and question why Emerson and colleagues felt the need to offer opinions on that evidence without providing any new contradictory empirical evidence for the region.
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Bruton, J. E., J. H. Jerome, and R. P. Bukata. "Satellite Observations of Sediment Transport Patterns in the Lac Saint-Pierre Region of the St. Lawrence River." Water Quality Research Journal 23, no. 2 (May 1, 1988): 243–52. http://dx.doi.org/10.2166/wqrj.1988.016.
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Abstract Satellite data from Landsats 4 and 5 were utilized to delineate the seasonal variations of sediment transport zones in the Lac Saint-Pierre region of the St. Lawrence River corridor. A seasonally cyclic succession of patterns displaying persistent, mutually independent, and extensive (in both space and time) turbidity zones was clearly in evidence. Visible and thermal data in both imagery and digital formats were used to show the close relationships existing among the distinct zonal synoptic patterns, the bathymetry of lake and river, and the near surface aquatic temperatures.
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Slack, B. "An Explanation of Port Activity on the South Shore of the Lower St.Lawrence Rive." Cahiers de géographie du Québec 17, no. 40 (April 12, 2005): 135–54. http://dx.doi.org/10.7202/021110ar.
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The study examines the factors that affect variations in port size in the region below Québec City on the south shore of the St. Lawrence River. The investigation draws upon the results of earlier studies and measures the relationships between six factors and port size. Multiple regression analysis produces a model that accounts for over 90 per cent of size variation in the port System.
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Lambert, Timothy C., and Shoukry N. Messieh. "Spawning Dynamics of Golf of St. Lawrence Herring (Clupea harengus)." Canadian Journal of Fisheries and Aquatic Sciences 46, no. 12 (December 1, 1989): 2085–94. http://dx.doi.org/10.1139/f89-258.
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Mean day of arrival of spawning herring (Clupea harengus) in the Gulf of St. Lawrence was calculated for different length groups by region and season. During the spawning season of both spring and autumn groups, herring arrived and deposited eggs on spawning grounds in decreasing order of age and length. Spawning bed surveys at two locations confirmed batch depositions of eggs which were correlated with the presence of dominant age-classes within the spawning population. Due to limitations of the port sampling procedure for collection of biological information routinely used in herring stock assessment, some length groups were underrepresented. This could result in the underestimation of the abundance of recruiting year-classes.
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Mellina, Eric, and Joseph B. Rasmussen. "Occurrence of Zebra Mussel (Dreissena polymorpha) in the intertidal Region of the St. Lawrence Estuary." Journal of Freshwater Ecology 9, no. 1 (March 1994): 81–84. http://dx.doi.org/10.1080/02705060.1994.9664430.
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Liu, Ning, Qing-Lai Dang, and William H. Parker. "Genetic variation of Populus tremuloides in ecophysiological responses to CO2 elevation." Canadian Journal of Botany 84, no. 2 (February 2006): 294–302. http://dx.doi.org/10.1139/b05-171.
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To investigate the genetic variation of trembling aspen ( Populus tremuloides Michx.) in ecophysiological responses to [CO2] elevation, 1-year-old seedlings of four provenances (three families per provenance) from northwestern Ontario were exposed to three [CO2] levels in the greenhouse: ambient (360 ppm), 1.5 × ambient (540 ppm), and 2 × ambient (720 ppm). Biomass and foliage gas exchange were examined after 60 d of treatment. [CO2] elevation significantly increased the rate of net CO2 assimilation and photosynthetic water use efficiency. The stimulation was generally greater in the 540 ppm [CO2] than in 720 ppm [CO2]. The 720 ppm [CO2] resulted in a 10% photosynthetic down-regulation, but no down-regulation was detected in the 540 ppm CO2 treatment. The 540 ppm [CO2] (but not the 720 ppm) treatment significantly decreased stomatal conductance and transpiration rate in the provenances from the Great Lakes – St. Lawrence Region but not in those from the Boreal Region. The intercellular to ambient CO2 concentration ratio (Ci/Ca) was significantly higher under 720 ppm [CO2] than under the other two [CO2]. The CO2 elevations generally increased the total and root biomass, and the stimulation was greater in the 540 ppm [CO2] than in the 720 ppm [CO2] treatment. The two provenances from the Great Lakes – St. Lawrence region generally had greater biomasses than those from the boreal region, while there were no significant differences between them in the physiological variables. However, we did not find any significant differences between provenances in the responses of biomass to [CO2] treatments.
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Lamontagne, Maurice. "Seismic activity and structural features in the Charlevoix region, Quebec." Canadian Journal of Earth Sciences 24, no. 11 (November 1, 1987): 2118–29. http://dx.doi.org/10.1139/e87-202.
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The Charlevoix region is historically the most active earthquake zone in eastern Canada. Understanding the links between its seismicity and the faults of the region is important for the assessment of earthquake risk along the St. Lawrence Valley. The region has been monitored by a microseismic array since 1977, yielding accurate locations of the hypocentres. Previous analyses of data from the array indicated a relationship between the earthquakes and the St. Lawrence Valley paleorift faults. As a sequel to previous studies, the relationships between the seismic activity and the faults of the region were reexamined through the use of the composite P-nodal solutions, in an effort to clarify the nature of faulting in the seismic zone. The microseisms were partitioned into subsets of events on the basis of geological and hypocentre-trend considerations. The main objectives of this paper are to delineate the details of faulting within the Charlevoix region and to determine the effect of the impact crater on the nature of faulting in this area.Assuming a constant 6.2 km/s velocity model and using a data set of 107 events, composite fault-plane solutions were computed. The composite P-nodal solutions indicated that the Charlevoix impact crater modifies to a certain extent the focal-mechanism characteristics. Events outside the impact crater were found to be quite consistent in their polarity distribution on the focal sphere, suggesting similarity in their focal mechanisms. The composite mechanism of these events suggests a relationship between the earthquakes and the north–south faults mapped outside the impact crater. The magnitude mb (Lg) 5.0 earthquake of August 19, 1979, the largest event in the selected time window, had different fault planes than some of its aftershocks. Nevertheless, the polarity distribution of the aftershocks was in agreement with the average trend for the events outside the crater. Events inside the impact crater were found to be produced along more variable fault orientations, with an average trend similar to that of the rift fault system. It is proposed that the meteor impact weakened the rift faults and introduced its own fractures. The present earthquake activity probably occurs along these weak fault surfaces. The effect of the impact crater on the type of faulting versus depth is not readily discernible from available data. In general, meteor impacts do not leave neotectonic seismic signatures: the Charlevoix impact crater might represent a different case because of the presence of weakened paleorift faults.
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Borns, Harold W., and Terence J. Hughes. "The implications of the Pineo Ridge readvance in Maine." Dynamique et paléogéographie de l’inlandsis laurentidien 31, no. 3-4 (January 17, 2011): 203–6. http://dx.doi.org/10.7202/1000272ar.
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Much of the Laurentide ice sheet in Maine, Atlantic Provinces, and southern Quebec was a "marine ice sheet," that is it was grounded below the prevailing sea level. When proper conditions prevailed, calving bays progressed into the ice sheet along ice streams partitioning it, leaving those portions grounded above sea level as residual ice caps. At least by 12,800 yrs. BP a calving bay had progressed up the St. Lawrence Lowland at least to Ottawa while a similar, but less extensive calving bay developed in Central Maine at approximately the same time. Concurrently, ice draining north into the St. Lawrence and south into the Central Maine calving bays rapidly lowered the surface of the intervening ice sheet until it eventually divided over the NE-SW trending Boundary and Longfellow Mountains and probably over other highland areas as well. A major consequence of these nearly simultaneous processes was the separation of an initial large ice cap over part of Maine, New Brunswick, and Québec which was bounded on the west by the calving bay in Central Maine, to the north by the calving bay in the St. Lawrence Lowland, to the south by the Bay of Fundy, and to the east by the Gulf of St. Lawrence. In coastal Maine, east of the calving bay, the margin of the ice cap receded above the marine limit at least 40 km and subsequently read-vanced terminating at Pineo Ridge moraine approximately 12,700 yrs. BP. These events are the stratigraphie and chronologic equivalent of the Cary-Pt. Huron recession/Pt. Huron readvance of the Great Lakes region.
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Plourde, Alexandre P., and Mladen R. Nedimović. "Earthquake Depths, Focal Mechanisms, and Stress in the Lower St. Lawrence Seismic Zone." Seismological Research Letters 92, no. 4 (May 5, 2021): 2562–72. http://dx.doi.org/10.1785/0220200429.
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Abstract We examine earthquake hypocenters, focal mechanisms, and the state of tectonic stress in the Lower St. Lawrence Seismic Zone (LSZ), a paleorift zone in eastern Canada. The largest earthquake recorded in the region is the 1999 Côte–Nord MN 5.1, which was followed by ∼80 aftershocks of MN>1. It is not known if the region is capable of producing hazardous Mw>6 earthquakes, similar to the Charlevoix Seismic Zone ∼250 km upriver. Focusing on 2015–2020, we apply a machine-learning-based phase picker to detect 72 earthquakes in addition to the 150 catalog earthquakes in the same region over this time span. We produce an updated 1D, gradient velocity model via a Monte Carlo search using a uniform VP/VS=1.77, which we computed with the Wadati method. We refine hypocenter estimates using the triple-difference method, with sP depth phases as additional constraints on earthquake depth. We estimate focal mechanisms for >100 earthquakes with automatically picked P-wave first motions and absolute value P-SV-SH amplitude ratios, and we use the focal mechanisms to invert for the state of tectonic stress. Grid searches and Bayesian analysis allow for robust uncertainty estimates of focal mechanisms, which in turn allow for uncertainty estimates of the stress tensor. The recovered west-northwest–east-southeast σ1 is consistent with previous estimates and with a stress tensor controlled by glacial isostatic adjustment, although a contrast between deep and shallow focal mechanisms suggests that these stresses may be concentrated in the lower crust. Epicenter lineations up to ∼40 km long may be indicative of sizable faults in the LSZ capable of generating Mw>6 earthquakes, but hypocenter and focal mechanism uncertainties are too high to say so definitively, thus pointing to a need for denser station coverage, including ocean-bottom seismometers.
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Davidson, A., J. Benckhuysen, and G. Francoeur. "Design of a Catamaran Sounding Vessel for Operation in the St. Lawrence." Marine Technology and SNAME News 32, no. 04 (October 1, 1995): 305–19. http://dx.doi.org/10.5957/mt1.1995.32.4.305.
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CCG Laurentian Region currently operates three vessels whose primary function is the sounding of dredged navigation channels in the St. Lawrence from Montreal to Gap Gribane, 15 km downstream from lle d'Orleans. The vessels also provide services as far out as Rimouski and into the Saguenay. These vessels sound, on an annual basis, some 120 km2 of surface area. Due to its association with Seaway dredging in which some 0.3 million m3 of material is removed annually, this sounding activity has to be carried out with an accuracy greater than that normally associated with hydrographic charting. CCG Laurentian Region specialists have brought together current off-the-shelf sounding and position-keeping equipment which comprise a sounding mission system capable of onboard real-time data processing compatible with significantly higher sounding speeds than the 10 knots of the existing fleet. The existing fleet, which comprises two 18 m catamaran vessels and the shipping channel maintenance vessel Nicolet, is now approaching the end of its economic life and is scheduled for replacement. The replacement program comprises two catamaran vessels designed to sound at 18 knots, thus providing full area coverage in the 8-month operating season from mid-April to mid-November. This paper presents some of the challenges represented by the mission requirement and the engineering solutions incorporated into the vessel design.
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Bassini-Silva, Ricardo, Fernando de Castro Jacinavicius, Josivania Soares Pereira, Karin Werther, Greg Sherwood Spicer, and Darci Moraes Barros-Battesti. "Parasitism of the nasal mite Sternostoma tracheacolum Lawrence, 1948 (Mesostigmata: Rhinonyssidae) in captive birds in Brazil." Revista Brasileira de Parasitologia Veterinária 28, no. 4 (December 2019): 754–59. http://dx.doi.org/10.1590/s1984-29612019053.
Full textAbstract:
Abstract Nasal mites (Mesostigmata: Rhinonyssidae) are obligatory endoparasites of birds, and the resulting parasitism can be harmful to the host’s respiratory system. The nasal mite Sternostoma tracheacolum Lawrence has caused significant respiratory issues, including serious injuries that possibly cause death of the host. In this study, we report two cases of captive birds parasitized by S. tracheacolum. The first case is a histopathological description of S. tracheacolum parasitizing the Gouldian Finch (Chloebia gouldiae) in the southeast region of Brazil, that showed partially or totally absence of the characteristic respiratory epithelium in trachea lumen. The other describes, for the first time, the parasitism of this species in a canary (Serinus canaria) in the northeast region of the country.
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Valentin, Alexandra E., Don Power, and Jean-Marie Sévigny. "Understanding recruitment patterns of historically strong juvenile year classes in redfish (Sebastes spp.): the importance of species identity, population structure, and juvenile migration." Canadian Journal of Fisheries and Aquatic Sciences 72, no. 5 (May 2015): 774–84. http://dx.doi.org/10.1139/cjfas-2014-0149.
Full textAbstract:
Genetic analyses were undertaken on archived otoliths from juveniles representing historically strong year classes of northwest Atlantic redfish (Sebastes spp.) and on tissue samples from adults of known species and population of origin. The results indicated that the species composition of a year class is key information for understanding recruitment dynamics, with redfish species having distinct population-associated patterns of spatial dispersion. In the Gulf of St. Lawrence – Laurentian Channel area (GSL–LCH), the last strong year class (which supported the fishery for more than 30 years) belonged to Sebastes mentella and originated from the area. In contrast, four year classes that appeared abundant at young ages in research surveys in GSL–LCH but contributed only marginally to the adult population and the fishery of the region belonged to Sebastes fasciatus and carried the genetic signature of the adult population from the slope of the Newfoundland Grand Banks. Ocean currents and spatiotemporal trends in abundance-at-length suggest that the latter population uses the Gulf of St. Lawrence as a nursery area, with larvae and early juveniles drifting toward the Gulf of St. Lawrence and older juveniles migrating back to the slope of the Grand Banks after about 5–6 years. It is suggested that juvenile migration behaviour is a postsettlement process that plays an important role in redfish recruitment dynamics and carries both demographic and evolutionary implications.