Fossil Coleoptera from the postglacial spruce–pine transition period near Minesing Swamp, Ontario

1987 ◽  
Vol 24 (10) ◽  
pp. 2099-2103 ◽  
Author(s):  
Randall F. Miller ◽  
W. D. Fitzgerald ◽  
D. N. Buhay
Keyword(s):  
Great Lakes ◽  
Boreal Forest ◽  
Climatic Change ◽  
Bark Beetles ◽  
Transition Period ◽  
Pollen Zone ◽  
Forest Region ◽  
Minesing Swamp ◽  
Insect Assemblage

Analysis of Coleoptera fragments from a woody peat overlain by alluvial sands, near the margin of Minesing Swamp, records the adjustment of the beetle fauna to climatic change at the time of the spruce–pine transition. The site, dated at 10 280 years BP, contains a small but interesting insect assemblage recovered from a 1 m section. Bark beetles and staphylinid beetles typical of the Boreal forest occur in the spruce pollen zone. Higher in the section bark beetles are absent, and staphylinid beetles typical of the Great Lakes – St. Lawrence Forest Region occur in the pine and hemlock pollen zones.

Paleoclimatic implications of a Late Wisconsinan insect assemblage from Rostock, southwestern Ontario

1987 ◽  
Vol 24 (4) ◽  
pp. 617-630 ◽  
Author(s):  
Jerry J. Pilny ◽  
Alan V. Morgan ◽  
Anne Morgan
Keyword(s):  
Boreal Forest ◽  
Tree Line ◽  
Mammuthus Primigenius ◽  
Forest Region ◽  
Clayey Silt ◽  
Cool Temperate ◽  
Temperate Environment ◽  
Late Wisconsinan ◽  
Geochemical Analyses ◽  
Insect Assemblage

The Rostock site is situated in a peat-covered wetland where fragments of a mammoth (Mammuthus primigenius) were unearthed in 1982. Excavation showed a descending sequence of peat, silty marl, gravel, clayey silt, and till. Approximately 300 kg of sediment was taken from the section for pollen, invertebrate, and geochemical analyses. The peat–marl transition is believed to be approximately contemporaneous with the spruce–pine transition in southern Ontario (ca. 10 600 years BP). A date of 10 790 ± 150 years BP on collagen from mammoth tusk fragments recovered from the same level substantiates this inference.Insects, especially Coleoptera, were common throughout the marl and represent at least 2000 individuals from 16 different families. On the basis of beetle ecologies and modern distributions, the marl was subdivided into lower and upper horizons. The lower horizon contains many species that are today restricted to western and northern North America. They are typical residents of the northern Boreal Forest Region and are frequently found on barren, sparsely vegetated ground. The upper horizon contains species found in and to the south of the boreal forest. Phytophagous species are more numerous and indicate a change from sparse to abundant vegetation. The insect assemblages suggest a shift from cold, tree-line conditions to a cool, temperate environment between approximately 13 000 and 11 000 years BP.

Fungi of the Canadian boreal forest region: Catulus aquilonius gen. et sp.nov., a hyperparasite on Seuratia millardetii

1978 ◽  
Vol 56 (19) ◽  
pp. 2344-2347 ◽  
Author(s):  
D. Malloch ◽  
C. T. Rogerson
Keyword(s):  
Boreal Forest ◽  
New Genus ◽  
New Genus And Species ◽  
Forest Region ◽  
Canadian Boreal Forest ◽  
Boreal Forest Region

A new genus and species of ascomycetes, Catulus aquilonius, is described, illustrated, and tentatively assigned to the Mycosphaerellaceae. It grows as a parasite on stromata of Seuratia millardetii (Raciborski) Meeker and is characterized by two-celled, setulose ascospores.

Summary and Synthesis: Past and Future Changes in the Alaskan Boreal Forest

2006 ◽  
Author(s):  
Marilyn W. Walker ◽  
Mary E. Edwards
Keyword(s):  
Boreal Forest ◽  
Bark Beetles ◽  
Fire Regime ◽  
Black Spruce ◽  
Rapid Change ◽  
White Spruce ◽  
Late Glacial ◽  
Fire Frequency ◽  
Tree Resistance ◽  
Forest Sites

Historically the boreal forest has experienced major changes, and it remains a highly dynamic biome today. During cold phases of Quaternary climate cycles, forests were virtually absent from Alaska, and since the postglacial re-establishment of forests ca 13,000 years ago, there have been periods of both relative stability and rapid change (Chapter 5). Today, the Alaskan boreal forest appears to be on the brink of further significant change in composition and function triggered by recent changes that include climatic warming (Chapter 4). In this chapter, we summarize the major conclusions from earlier chapters as a basis for anticipating future trends. Alaska warmed rapidly at the end of the last glacial period, ca 15,000–13,000 years ago. Broadly speaking, climate was warmest and driest in the late glacial and early Holocene; subsequently, moisture increased, and the climate gradually cooled. These changes were associated with shifts in vegetation dominance from deciduous woodland and shrubland to white spruce and then to black spruce. The establishment of stands of fire-prone black spruce over large areas of the boreal forest 5000–6000 years ago is linked to an apparent increase in fire frequency, despite the climatic trend to cooler and moister conditions. This suggests that long-term features of the Holocene fire regime are more strongly driven by vegetation characteristics than directly by climate (Chapter 5). White spruce forests show decreased growth in response to recent warming, because warming-induced drought stress is more limiting to growth than is temperature per se (Chapters 5, 11). If these environmental controls persist, projections suggest that continued climate warming will lead to zero net annual growth and perhaps the movement of white spruce to cooler upland forest sites before the end of the twenty-first century. At the southern limit of the Alaskan boreal forest, spruce bark beetle outbreaks have decimated extensive areas of spruce forest, because warmer temperatures have reduced tree resistance to bark beetles and shortened the life cycle of the beetle from two years to one, shifting the tree-beetle interaction in favor of the insect (Chapter 9).

Kraft Pulping and Specific Gravity in the Uppermost Stem of Fertilized Balsam Fir

1975 ◽  
Vol 5 (3) ◽  
pp. 399-402 ◽  
Author(s):  
J. D. Gagnon ◽  
K. Hunt
Keyword(s):  
Specific Gravity ◽  
Boreal Forest ◽  
Kraft Pulping ◽  
Balsam Fir ◽  
Pulp Yield ◽  
Kraft Process ◽  
Forest Region ◽  
The Mean ◽  
Boreal Forest Region

Samples of five pairs of fertilized and non-fertilized 60-year-old natural balsam fir (Abiesbalsamea (L.) Mill.) growing in the Quebec boreal forest region were pulped by the kraft process and the specific gravity was measured. Analyses carried out 7 years after treatment on the last seven terminal internodes revealed the mean pulp yield of trees fertilized exceeded that of non-fertilized by 7%, while the mean specific gravity was about 6% lower.

Climatic change and great lakes levels the impact on shipping

1988 ◽  
Vol 12 (2) ◽  
pp. 107-133 ◽  
Author(s):  
D. Marchand ◽  
M. Sanderson ◽  
D. Howe ◽  
C. Alpaugh
Keyword(s):  
Great Lakes ◽  
Climatic Change ◽  
The Impact
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