scholarly journals Vegetation and Climate of Maritime Canada 6000 Years BP: A Synthesis

2007 ◽  
Vol 49 (1) ◽  
pp. 141-162 ◽  
Author(s):  
Hélène Jetté ◽  
Robert J. Mott

ABSTRACT Environmental conditions (vegetation and climate) of Maritime Canada are reconstructed as a regional contribution to a national synthesis on the paleoenvironment of Canada 6000 yr BP. Ten new sites, including three complete sequences and seven short sequences bracketing the 6 ka period, are added to the existing pollen dataset for this region. The vegetation prevalent 6000 yr BP in New Brunswick was a mixed coniferous-deciduous forest with pine, mostly white pine (Pinus strobus) in the northwest, and a mixed coniferous-deciduous forest with hemlock (Tsuga canadensis) in the south and southeast. In the northwest, fir (Abies) replaced pine at high elevations and a boreal forest grew on the New Brunswick Highlands. The dominant vegetation at 6000 yr BP in Prince Edward Island and Nova Scotia was a mixed coniferous-deciduous forest with hemlock dominating. Cape Breton Island was covered by a mixed coniferous-deciduous forest with pine and/or fir, except for the southern part of the Island where hemlock was probably present. Analysis of the fossil sites indicate that a warm-dry period influenced the composition of the vegetation 6000 yr BP.

2014 ◽  
Vol 127 (4) ◽  
pp. 332 ◽  
Author(s):  
Paul M. Catling ◽  
Donald F. McAlpine ◽  
Christopher I. G. Adam ◽  
Gilles Belliveau ◽  
Denis Doucet ◽  
...  

Chortophaga viridifasciata, Forficula auricularia, Melanoplus stonei, Scudderia furcata furcata, Scudderia pistillata, and Trimerotropis verruculata from Prince Edward Island and Doru taeniatum, Melanoplus punctulatus, Orchelimum gladiator, and Spharagemon bolli from New Brunswick are new provincial records. Other records of interest include the endemic Melanoplus madeleineae from Île d’Entrée in the Îles-de-la-Madeleine, Quebec; Trimerotropis verruculata from the Îles-de-la-Madeleine, Quebec; and Chortophaga viridifasciata, Stethophyma lineatum, and Tetrix subulata, new for Cape Breton Island, Nova Scotia. The ranges of Conocephalus brevipennis, Tetrix arenosa angusta, Tetrix ornata, and Tetrix subulata are significantly extended in New Brunswick. A previously unpublished record from 2003 of Roeseliana roeselii (Metrioptera roeselii) is the earliest report of this European introduction to the Maritimes.


2009 ◽  
Vol 46 (3) ◽  
pp. 169-180 ◽  
Author(s):  
Peter H. Reynolds ◽  
Sandra M. Barr ◽  
Chris E. White

We report single-grain ages for detrital muscovite separated from sandstone samples from five localities in southern New Brunswick and southeastern Cape Breton Island, Nova Scotia, and from two quartzite clasts from a quartzite-pebble conglomerate that underlies the sampled sandstone units in New Brunswick. The oldest detrital grains were found in one of the quartzite clasts; their age range, ca. 650−630 Ma, is defined not only by the single-grain analyses but also by spot dating (using a UV laser) within a single large grain, suggesting that these grains came from a single source. The second quartzite clast has a blastomylonitic fabric with muscovite “fish,” and most of the muscovite ages have been partially reset (at ca. 550 Ma) from the original ca. 650–630 Ma ages. The age distribution plots obtained for the sandstone samples suggest the presence of muscovite that still retains the original source age, but most of the grains have been partially reset by the same ca. 550 Ma event that reset muscovite ages in the second quartzite clast. We suggest that the quartzite source that produced the two clasts was also the source of muscovite in the Avalonian Cambrian rocks of Maritime Canada. The original source rock was likely a metamorphic or perhaps granitic rock unit situated relatively proximal to the site of deposition of the quartzite protolith, but the actual source is not known, and locally, no potential candidates are exposed. The resetting event at ca. 550 Ma may be linked to initial stages of regional transtension associated with rifting of Avalonia from Gondwana.


Zootaxa ◽  
2007 ◽  
Vol 1654 (1) ◽  
pp. 1-20 ◽  
Author(s):  
CHRISTOPHER G. MAJKA

The Ciidae of the Maritime Provinces of Canada are surveyed. Fifteen species are now known to occur in the region, thirteen in Nova Scotia, six in New Brunswick, and two on Prince Edward Island. Ten new provincial records  are reported. Seven species including Ceracis sallei Mellié, Ceracis thoracicornis (Ziegler), Cis creberrimus Mellié, Cis pistoria Casey, Cis subtilis Mellié, Malacocis brevicollis (Casey), and Orthocis punctatus (Mellié) are newly recorded in the Maritime Provinces as a whole. Cis americanus Mannerheim and Cis levettei (Casey) are newly recorded on Prince Edward Island, the first records of this family from the province.Collecting effort on Cape Breton Island, Prince Edward Island, and in New Brunswick has apparently been insufficient to fully document the ciid fauna of these areas. Some local and regional distribution patterns of ciids in the mainland of Nova Scotia and in the Maritime Provinces are suggested from the present data, but further collecting is required to confirm these. Zoogeographically, most of the region's ciids are members of either a boreal fauna (9 species) with Holarctic affinities, or a southeastern North American Nearctic fauna (5 species). The Maritime Provinces ciid fauna has representatives of five of the six known ciid host-use groups. Records of host fungi indicate that there are suitable hosts for all species of ciids found in the region in all three Maritime Provinces, indicating that ciids in the region appear not to be limited by availability of suitable host-fungi. However, Cis horridulus Casey, Cis striolatus Casey, and Cis subtilis Mellié, the three species in the Trametes host-use group, are very infrequently collected and apparently rare.Forests in Maritime Provinces have been greatly affected by forestry and disease, and such activities are known to impact fungal communities. Consequently such practices could have important repercussions for groups like the Ciidae that are reliant on fungi as both a food source and a habitat


2009 ◽  
Vol 141 (4) ◽  
pp. 317-370 ◽  
Author(s):  
Christopher G. Majka ◽  
David Langor ◽  
Wolfgang H. Rücker

AbstractThirty-five species of Latridiidae are reported in Atlantic Canada as a whole, 17 in New Brunswick, 14 in Newfoundland, 31 in Nova Scotia, and 14 on Prince Edward Island. Fifty-six new provincial records are reported (11 in New Brunswick, 9 in Newfoundland, 23 in Nova Scotia, 13 in Prince Edward Island). Twenty-two species are newly recorded for Atlantic Canada. Of these, Cartodere (Aridius) bifasciata (Reitter), Enicmus histrio Joy and Tomlin, Latridius consimilis (Mannerheim), Corticaria elongata (Gyllenhal), C. impressa (Olivier), C. saginata Mannerheim, Corticarina longipennis (LeConte), Melanophthalma helvola Motschulsky, and M. inermis Motschulsky are newly recorded in Canada, and C. bifasciata, E. histrio, and C. saginata are newly recorded in North America. Dienerella filiformis (Gyllenhal) is removed from the New Brunswick and Prince Edward Island lists. Corticaria dentigera LeConte is removed from the Labrador and Atlantic Provinces lists. Melanophthalma inculta Motschulsky syn. nov. and M. signata Belon syn. nov. are designated as a junior synonyms of M. inermis Motschulsky and M. picta (LeConte), respectively. Melanophthalma helvola Motschulsky is reinstated as a valid species. Lectotypes and paralectotypes of M. helvola and M. americana (Mannerheim) are designated. Approximately half of the species are adventive (16 Palaearctic, 1 Australian) and half are native (13 Nearctic, 3 Holarctic). Two species are of uncertain zoogeographic status. Although some species are synanthropic, several have colonized native habitats. Nova Scotia has the largest number of adventive species, probably as a result of trans-Atlantic shipping. New Brunswick has the fewest, at least in part because of insufficient collecting there. Early detection dates and introduction processes are discussed. The native faunas on Prince Edward Island, Cape Breton Island, and Newfoundland appear diminished (33%–40%) compared with those of the neighbouring mainland. Although all latridiids are mycetophagous, many in the region show clear habitat preferences; however, the ecological role of those species requires further investigation.


2008 ◽  
Vol 140 (1) ◽  
pp. 128-141 ◽  
Author(s):  
Christopher G. Majka ◽  
Yves Bousquet ◽  
Christine Noronha ◽  
Mary E. Smith

AbstractFourteen species of Carabidae are added to Prince Edward Island’s (P.E.I.) faunal list, bringing the known fauna to 167 species. Bembidion nitidum (Kirby) and Bembidion obtusum Audinet-Serville are newly recorded for the Maritime Provinces. Six species are removed from P.E.I.’s faunal list. The history of collecting of Carabidae on P.E.I. is briefly recounted. Despite differences in land area and distance from the mainland between P.E.I., Cape Breton Island, and insular Newfoundland, their carabid faunas exhibit many similarities in size and composition. The native carabid fauna of P.E.I. comprises 49% of the species in the combined Maritime Provinces fauna, perhaps reflecting an island-related diminution of species diversity. The proportion of flightless species on P.E.I. (4.9%) is less than that in the Maritime Provinces as a whole (7.1%), an apparent indication that the Northumberland Strait has been a barrier to colonization. Twenty-seven introduced species are found on P.E.I., 26 of which can be classified as synanthropic and may have originated in dry-ballast quarries in southwestern England. Although the earliest dates of detection of many introduced species on P.E.I. are substantially later than elsewhere in the Maritimes, this reflects the paucity of early collecting. Land-management practices on P.E.I. (large-scale and early forest clearances, intensive agriculture, and the extensive use of biocides) may have had an impact on P.E.I.’s carabid fauna.


2007 ◽  
Vol 44 (11) ◽  
pp. 1551-1565 ◽  
Author(s):  
Lori A Cook ◽  
Sonya A Dehler ◽  
Sandra M Barr

A prominent positive magnetic anomaly spans the 100 km distance between Prince Edward Island and Cape Breton Island in the southern Gulf of St. Lawrence. The anomaly occurs in an area of complex structure where Appalachian terrane boundaries are poorly resolved because of thick late Paleozoic sedimentary cover. Analysis of the magnetic anomaly led to the interpretation that it is produced by four separate, approximately circular, source bodies aligned along the northwesterly trend of the anomaly. Seismic data, physical property measurements, and magnetic and gravity anomalies were used to further investigate the anomaly sources through forward modeling techniques. The four source bodies have densities and magnetic susceptibilities compatible with dioritic to granitic compositions. Modeling also suggests that basement to the north of the plutons has higher density and susceptibility than basement to the south, and hence the source bodies are interpreted as plutons emplaced along the boundary between Ganderian composite terranes to the north and the Ganderian Brookville – Bras d’Or terrane to the south. This interpretation suggests that the Ganderia–Avalonia boundary is located farther south, and shows the need for re-evaluation of the location and role of the Canso fault in offsetting terranes between Cape Breton Island and southern New Brunswick.


1997 ◽  
Vol 34 (2) ◽  
pp. 156-168 ◽  
Author(s):  
R. D. Dallmeyer ◽  
J. D. Keppie ◽  
R. D. Nance

Detrital muscovite from lowermost Cambrian sequences exposed in the Avalon Composite Terrane in Nova Scotia and New Brunswick record 40Ar/39Ar plateau ages of ca. 625–600 Ma. These are interpreted to date times of cooling in source areas. The regional distribution of coarse-grained detrital muscovite in Lower Cambrian rocks of Avalonian overstep sequences suggests a source region of dimensions considerably larger than any presently exposed in Appalachian segments of the Avalon Composite Terrane. Late Proterozoic tectonic reconstructions locate the Avalon Composite Terrane adjacent to northwestern South America, thereby suggesting a possible source within Late Proterozoic PanAfrican – Brasiliano orogens. Detrital muscovite from clastic sequences of the proximally derived, Lower Carboniferous (Tournaisian) Horton Group and the more distal Upper Carboniferous (Westphalian D – Stephanian) Pictou Group in Nova Scotia records 40Ar/39Ar spectra that define plateau ages of ca. 390–380 Ma (Horton Group) and and ca. 370 Ma (Pictou Group). Finer grained fractions from samples of the Horton Group display more internally discordant age spectra defining total-gas ages of ca. 397–395 Ma. A provenance for the finer muscovite may be found in southern Nova Scotia where Cambrian–Ordovician turbidites of the Meguma Group display a regionally developed micaceous cleavage of this age. The ca. 390–380 Ma detrital muscovites probably were derived from granite stocks presently exposed in proximal areas of northernmost Cape Breton Island. A more distal source for the ca. 370 Ma detrital muscovites in the Pictou Group is suggested by its original extensive distribution, although a local, possibly recycled, source may also have been present. The presence of only 400–370 Ma detrital muscovite suggests a rapidly exhumed orogenic source with characteristics similar to those of crystalline rocks presently exposed in the Cape Breton Highlands and (or) the Meguma Terrane.


Zootaxa ◽  
2007 ◽  
Vol 1546 (1) ◽  
pp. 39-50 ◽  
Author(s):  
CHRISTOPHER G. MAJKA

The Erotylidae and Endomychidae of the Maritime Provinces are surveyed. Fifteen species are now known from the region, fourteen in Nova Scotia, seven in New Brunswick, and four on Prince Edward Island. Thirteen new provincial records (seven from Nova Scotia, three from New Brunswick, and three from Prince Edward Island) are reported. Four erotylids, Dacne quadrimaculata (Say), Triplax dissimulator (Crotch), Triplax flavicollis Lacordaire, Triplax macra LeConte; and two endomychids, Rhanidea unicolor (Ziegler) and Lycoperdina ferruginea LeConte, are newly recorded in the Maritime Provinces as a whole. New records of the rare endomychid, Hadromychus chandleri Bousquet & Leschen, are reported. The fauna is examined in a regional zoogeographic context, paying particular attention to the insular faunas of Cape Breton and Prince Edward Islands. Attention is also drawn to the number of species that have been very rarely collected. This apparent scarcity may be related to the long history of forest management in the region, in particular the effects of intensive forestry on the communities of forest fungi on which these species feed and depend. Attention is drawn to the importance of ongoing research to monitor their populations and assess how these species may be employed as indicators of the overall health forest ecosystems.


2000 ◽  
Vol 137 (2) ◽  
pp. 137-153 ◽  
Author(s):  
J. D. KEPPIE ◽  
J. DOSTAL ◽  
R. D. DALLMEYER ◽  
R. DOIG

Isotopic and geochemical data indicate that intrusions in the eastern Creignish Hills of central Cape Breton Island, Canada represent the roots of arcs active at ∼ 540–585 Ma and ∼ 440 Ma. Times of intrusion are closely dated by (1) a nearly concordant U–Pb zircon age of 553±2 Ma in diorites of the Creignish Hills pluton; (2) a lower intercept U–Pb zircon age of 540±3 Ma that is within analytical error of 40Ar/39 Ar hornblende plateau isotope-correlation ages of 545 and 550±7 Ma in the River Denys diorite; and (3) an upper intercept U–Pb zircon age of 586±2 Ma in the Melford granitic stock. On the other hand, ∼ 441–455 Ma 40Ar/39 Ar muscovite plateau ages in the host rock adjacent to the Skye Mountain granite provide the best estimate of the time of intrusion, and are consistent with the presence of granitic dykes cutting the Skye Mountain gabbro–diorite previously dated at 438±2 Ma. All the intrusions are calc-alkaline; the Skye Mountain granite is peraluminous. Trace element abundances and Nb and Ti depletions of the intrusive rocks are characteristic of subduction-related rocks. The ∼ 540–585 Ma intrusions form part of an extensive belt running across central Cape Breton Island, and represent the youngest Neoproterozoic arc magmas in this part of Avalonia. Nearby, they are overlain by Middle Cambrian units containing rift-related volcanic rocks, which bracket the transition from convergence to extension between ∼ 540 and 505/520 Ma. This transition varies along the Avalon arc: 590 Ma in southern New England, 560–538 Ma in southern New Brunswick, and 570 Ma in eastern Newfoundland. The bi-directional diachronism in this transition is attributed to northwestward subduction of two mid-ocean ridges bordering an oceanic plate, and the migration of two ridge–trench–transform triple points. Following complete subduction of the ridges, remnant mantle upwelling along the subducted ridges produced uplift, gravitational collapse and the high-temperature/low-pressure metamorphism in the arc in both southern New Brunswick and central Cape Breton Island. The ∼ 440 Ma arc magmatism in the Creignish Hills extends through the Cape Breton Highlands and into southern Newfoundland, and has recently been attributed to northwesterly subduction along the northern margin of the Rheic Ocean.


2007 ◽  
Vol 139 (3) ◽  
pp. 397-442 ◽  
Author(s):  
Christopher G. Majka ◽  
Robert S. Anderson ◽  
David B. McCorquodale

AbstractSeventy-nine species of weevils are newly reported in Nova Scotia and 66 species are newly reported on Prince Edward Island, increasing the known provincial weevil faunas to 244 and 92 species, respectively. Thirty-six species are recorded for the first time in the Maritime Provinces; of these, Ceutorhynchus pallidactylus (Marsham), Listronotus dietzi O'Brien, Corthylus columbianus Hopkins, and Orchidophilus aterrimus (Waterhouse) are recorded for the first time in Canada. Orchidophilus aterrimus has been collected only in exotic domesticated orchids and is not established in the wild. Fourteen species previously recorded on Cape Breton Island, Nova Scotia, are reported from the provincial mainland. Four species — Curculio sulcatulus (Casey), Ceutorhynchus squamatus LeConte, Tachyerges niger (Horn), and Ips calligraphus (Germar) — are removed from the faunal list of Nova Scotia, and three species — Temnocerus cyanellus (LeConte), Curculio nasicus (Say), and Cryphalus ruficollis ruficollis Hopkins — are removed from the faunal list of Prince Edward Island. The combined known weevil fauna of the Maritime Provinces now totals 290 species. The adequacy of collection effort is discussed and in Nova Scotia, where collection effort has been greatest, distribution patterns of selected groups of species are examined. Island faunas are discussed with respect to those of Prince Edward Island and Cape Breton Island. Regional biogeographic patterns of species are also discussed, including possible disjunct populations in Nova Scotia and species that may not have crossed the isthmus of Chignecto to colonize Nova Scotia. Attention is drawn to the long history of introduced species in the region and to ongoing introductions through an examination of the earliest records for the 60 introduced species found in the region.


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