Roads, logging, and the large-mammal community of an eastern Canadian boreal forest

2010 ◽  
Vol 88 (5) ◽  
pp. 454-467 ◽  
Author(s):  
Jeff Bowman ◽  
Justina C. Ray ◽  
Audrey J. Magoun ◽  
Devin S. Johnson ◽  
F. Neil Dawson

We evaluated hypotheses concerning the distributions of large mammals in a 60 000 km2 study area that encompassed the contact zone between Ontario’s roadless north and the postlogging southern landscape. We estimated occurrence probability in 575 sample units for woodland caribou ( Rangifer tarandus caribou (Gmelin, 1788)), wolverine ( Gulo gulo (L., 1758)), gray wolf ( Canis lupus L., 1758), moose ( Alces alces (L., 1758)), and white-tailed deer ( Odocoileus virginianus (Zimmerman, 1780)). We used ordinations and spatial regressions to assess the contributions of parameters to species occurrence. Roads and cutovers were most abundant in the south, leading to an increased prevalence of deciduous forest. Mature coniferous forest, however, occurred most commonly in the north. Occurrence probabilities for moose and deer were greatest in the south, in close association with deciduous trees. Wolf occurrence was also greatest in the south, positively related to both deciduous forest and road density. Caribou occurrence, however, was positively related to mature coniferous forest and negatively related to both wolf occurrence and roads. Wolverine occurrence was negatively related to deciduous forest. Our surveys demonstrated distinct mammal communities in the northern and southern halves of our study area, a separation that appeared to be mediated by deciduous forest and roads.

2021 ◽  
Vol 38 ◽  
pp. 00102
Author(s):  
Ekaterina Popova ◽  
Evgeniy Sinkovskiy

The paper presents a taxonomic, areographic and belt-andzonal analysis of the high-mountain flora of the Kurai Ridge. The flora of the region in question contains 312 species of plants, referred to 143 genera belonging to 48 families. Analysis of the taxonomic structure of the high-mountain flora of the Kurai Ridge has shown the following most abundant plant families: Asteraceae, Ranunculaceae, and Poaceae. For the variety of the genera, the following genera are predominant: Carex, Pedicularis, Salix, and Oxytropis. The areographic analysis has demonstrated that the said species are of the North Asian (21 %), South Siberian (19.4 %) and Holarctic (17.4 %) origins. Dominant in the belt-and-zonal range are the following species: high-mountain (23.2 %), light-coniferous forest (17.7 %) and Arctic Alpine (17.4 %) species. In general, the composition and structure of the high-mountain flora of the Kurai Ridge are determined by its geographic position at the boundary of Central and South-Eastern Altai and by decrease in the amount of precipitation in the south-eastern direction.


Rangifer ◽  
1991 ◽  
Vol 11 (4) ◽  
pp. 116
Author(s):  
Scott R. Robinson

A resident herd of caribou (Rangifer tarandus granti) inhabits the Koyukuk River valley and Kokrines Hills, which are located on the north side of the Yukon River near the Alaskan villages of Galena and Ruby. Personnel from the Alaska Departement of Fish and Game, U.S. Bureau of land Management, and U.S. Fish and Wildlife Service studied this herd from October 1983 to January 1990. The highest caribou count was 258 in June 1987. The proportion of newborn calves observed during the May calving period ranged from 0 to 28% (mean=10%) whereas it ranged from 4 to 17% (mean=13%) in October. Caribou inhabited mostly coniferous forest from October through April and open habitat from May through September. Male caribou occupied fewer habitat types, travelled less distance, and remained at lower elevations than female caribou. Management concerns for this herd are discussed.


1979 ◽  
Vol 45 ◽  
pp. 1-33 ◽  
Author(s):  
G. J. Wainwright ◽  
A. Fleming ◽  
K. Smith

Viewed from the south Devon littoral with its series of good harbours the dark bulk of Dartmoor is clearly visible across the flat coastal plain. It is the largest of the five granite masses that provide a spine to the south-west English peninsula (Dartmoor, Bodmin Moor, Hensbarrow, Carnmenellis and Penwith) that were formed by the consolidation of molten material. The 500 square kilometres of the Moor form an undulating upland up to 600 m OD on the north-east side, where the greatest elevations occur. In the southern parts of the Moor the rolling tableland is 300 m to 420 m high—modern cultivation tends to cease at the 300 m contour, that is broken by numerous upland valleys and the eroded remains of tors. Today this expanse of moorland is bleak and treeless except in river valleys at the rim of the granite escarpment, although patches of contorted oak woodland survive at Piles' Wood on the River Erme, Wistman's Wood on the West Dart and Black Tor Beare on the West Okement. Pollen analyses have shown, however, that up to a height of about 360 m Dartmoor was probably covered by a deciduous forest dominated by oak that was gradually eroded by climatic trends and human activity (e.g. Simmons, 1969). It is from this central mass that the rivers of south Devon diverge. The wide upland valleys of the Tavy, Plym, Yealm, Erme, Avon and Dart plunge through characteristic deep wooded gorges near the southern granite escarpment into the South Hams and around this border modern settlement—numerous villages and a few towns are situated.


Polar Record ◽  
1981 ◽  
Vol 20 (127) ◽  
pp. 337-352 ◽  
Author(s):  
Ian Whitaker

Among students of the history of reindeer domestication the Tuva occupy a special position. Their homeland, the Sayan mountains and the basin of the upper Yenisey, to the south-west of lake Baykal and to the north of the present-day frontier between the USSR and Mongolia, has frequently been suggested as the region where reindeer were first domesticated. This attribution rests on two types of evidence: the first archaeological, and largely consisting of rock carvings depicting reindeer; and the second ethnographic, comprising observations of the techniques of reindeer management employed by the Tuva, chiefly made by two western travellers, the Englishman Douglas Carruthers in 1910, and the Norwegian Ørjan Olsen in 1914. The fieldwork of Olsen has only been published in Norwegian (Olsen, 1915a; 1915b), and therefore has not been widely used by scientists. Yet of the two travellers he was perhaps better equipped to make technical ethnographic observations. In this article I shall analyse the descriptions of reindeer husbandry made by both men, but with especial attention to Olsen. I shall then assess the contribution that observations of the Tuva might make to the debate between ethnologists on where reindeer (Rangifer tarandus L) were first domesticated.


2000 ◽  
Vol 179 ◽  
pp. 201-204
Author(s):  
Vojtech Rušin ◽  
Milan Minarovjech ◽  
Milan Rybanský

AbstractLong-term cyclic variations in the distribution of prominences and intensities of green (530.3 nm) and red (637.4 nm) coronal emission lines over solar cycles 18–23 are presented. Polar prominence branches will reach the poles at different epochs in cycle 23: the north branch at the beginning in 2002 and the south branch a year later (2003), respectively. The local maxima of intensities in the green line show both poleward- and equatorward-migrating branches. The poleward branches will reach the poles around cycle maxima like prominences, while the equatorward branches show a duration of 18 years and will end in cycle minima (2007). The red corona shows mostly equatorward branches. The possibility that these branches begin to develop at high latitudes in the preceding cycles cannot be excluded.


Author(s):  
Esraa Aladdin Noori ◽  
Nasser Zain AlAbidine Ahmed

The Russian-American relations have undergone many stages of conflict and competition over cooperation that have left their mark on the international balance of power in the Middle East. The Iraqi and Syrian crises are a detailed development in the Middle East region. The Middle East region has allowed some regional and international conflicts to intensify, with the expansion of the geopolitical circle, which, if applied strategically to the Middle East region, covers the area between Afghanistan and East Asia, From the north to the Maghreb to the west and to the Sudan and the Greater Sahara to the south, its strategic importance will seem clear. It is the main lifeline of the Western world.


Author(s):  
A., C. Prasetyo

Overpressure existence represents a geological hazard; therefore, an accurate pore pressure prediction is critical for well planning and drilling procedures, etc. Overpressure is a geological phenomenon usually generated by two mechanisms, loading (disequilibrium compaction) and unloading mechanisms (diagenesis and hydrocarbon generation) and they are all geological processes. This research was conducted based on analytical and descriptive methods integrated with well data including wireline log, laboratory test and well test data. This research was conducted based on quantitative estimate of pore pressures using the Eaton Method. The stages are determining shale intervals with GR logs, calculating vertical stress/overburden stress values, determining normal compaction trends, making cross plots of sonic logs against density logs, calculating geothermal gradients, analyzing hydrocarbon maturity, and calculating sedimentation rates with burial history. The research conducted an analysis method on the distribution of clay mineral composition to determine depositional environment and its relationship to overpressure. The wells include GAP-01, GAP-02, GAP-03, and GAP-04 which has an overpressure zone range at depth 8501-10988 ft. The pressure value within the 4 wells has a range between 4358-7451 Psi. Overpressure mechanism in the GAP field is caused by non-loading mechanism (clay mineral diagenesis and hydrocarbon maturation). Overpressure distribution is controlled by its stratigraphy. Therefore, it is possible overpressure is spread quite broadly, especially in the low morphology of the “GAP” Field. This relates to the delta depositional environment with thick shale. Based on clay minerals distribution, the northern part (GAP 02 & 03) has more clay mineral content compared to the south and this can be interpreted increasingly towards sea (low energy regime) and facies turned into pro-delta. Overpressure might be found shallower in the north than the south due to higher clay mineral content present to the north.


2002 ◽  
pp. 22-31 ◽  
Author(s):  
T. V. Maltseva ◽  
N. I. Makunina

The North-Eastern Altai is an ultra-humid area with climax vegetation represented by tall-herb fir (Abies sibirica) dark-coniferous forest. Its meadows belong to the class Molinio-Arrhenatheretea. The typical asso­ciation Aegopodio podagrariae—Dactyletum glomeratae originates in the watershed clearings after climax forests whereas ass. Hyperici perforati—Agrostietum giganteaereplaces the previous one under mowing and grazing. The Molinietalia wet meadows are widespread in the river valleys. The meadows of ass. Cirsio heterophylli—Calama­grostietum langsdorffii occur on wet soils in small depressions and along floodplain mire margins, and ass. Ca­rici ovalis—Deschampsietum cespitosae comprises typical floodplain hay-meadows on moist, nutrient-rich soils.


2019 ◽  
Author(s):  
Hamed D. Ibrahim

North and South Atlantic lateral volume exchange is a key component of the Atlantic Meridional Overturning Circulation (AMOC) embedded in Earth’s climate. Northward AMOC heat transport within this exchange mitigates the large heat loss to the atmosphere in the northern North Atlantic. Because of inadequate climate data, observational basin-scale studies of net interbasin exchange between the North and South Atlantic have been limited. Here ten independent climate datasets, five satellite-derived and five analyses, are synthesized to show that North and South Atlantic climatological net lateral volume exchange is partitioned into two seasonal regimes. From late-May to late-November, net lateral volume flux is from the North to the South Atlantic; whereas from late-November to late-May, net lateral volume flux is from the South to the North Atlantic. This climatological characterization offers a framework for assessing seasonal variations in these basins and provides a constraint for climate models that simulate AMOC dynamics.


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