Geography and Bathymetry of Selected Lake Basins, Experimental Lakes Area, Northwestern Ontario

1971 ◽  
Vol 28 (2) ◽  
pp. 139-155 ◽  
Author(s):  
G. J. Brunskill ◽  
D. W. Schindler
Keyword(s):  
Black Spruce ◽  
Soil Depth ◽  
White Birch ◽  
Lake Agassiz ◽  
Preliminary Calculation ◽  
Experimental Lakes Area ◽  
Glacial Ice ◽  
Winnipeg River ◽  
Sand And Gravel ◽  
Lake Basins

The Experimental Lakes Area (ELA) is located at 93°30′–94°00′W and 49°30′–49°45′N at an altitude of 360–380 m above mean sea level. This area is underlain by Precambrian acid granites overlain in some areas by thin glacial drift composed largely of sand and gravel of quartz, plagioclase, and K-feldspar. The area was under glacial ice about 14,000 years B.P. (before present). With the melting of this glacial ice, ELA was situated on the eastern margin of glacial Lake Agassiz. As Lake Agassiz levels receded, the present lake basins were formed. The ELA watersheds now drain into the Winnipeg River, which is in the Hudson Bay drainage system.Mean annual temperatures in the vicinity of ELA are between 0.5 and 2.2 C, and annual precipitation is between 500 and 750 mm. Brunisols were observed over sand deposits in the ELA, but considerable variation in soil types and soil depth were also found. ELA is in a boreal (fire-controlled) subclimax forest of jack pine, black spruce, trembling aspen, and white birch. Aquatic macrophytes were scarce in the littoral zone of ELA lakes. Nearby logging operations and hunting and sport fishing have not influenced the immediate watersheds of ELA lakes.Morphometric maps and measurements are given for 16 lakes in ELA. These lakes vary from 2.5 to 33 m in maximum depth, and from 1.7 to 56 ha in lake surface area. Using estimates of precipitation, evaporation, evapotranspiration, drainage areas, and lake morphometry, a preliminary calculation of theoretical water renewal time is given for these lakes. These values range from 2.6 to 38 years.

The Mosbeck Site: a Paleoenvironmental Interpretation of the Late Quaternary History of Lake Agassiz Based on Fossil Insect and Mollusk Remains

1972 ◽  
Vol 2 (02) ◽  
pp. 176-188 ◽  
Author(s):  
Allan C. Ashworth ◽  
Lee Clayton ◽  
William B. Bickley
Keyword(s):  
Black Spruce ◽  
Late Quaternary ◽  
Small Body ◽  
Open Water ◽  
Fine Sand ◽  
Silty Sand ◽  
Silty Clay ◽  
Lake Agassiz ◽  
Fossil Insect ◽  
Sand And Gravel

The Mosbeck Site is in the southern part of the Lake Agassiz basin in northwestern Minnesota. The stratigraphic section at the site consists of seven lithologic units, which are from bottom to top (A) unsorted, pebbly, sandy, silty clay, (B) coarse gravel, (C) silty sand, (D) peat, (E) fine sand, (F) interbedded sand and gravel, and (G) unbedded dirty gravel. The lower few centimeters of unit E are unoxidized and contain black spruce and tamarack driftwood, which has been radiocarbon dated at 9940 ± 160 BP (I-3880). Units C-E contain numerous, well-preserved insect and mollusk remains. These fossils have been compared with modern species, and at least 76 insect and 15 mollusk taxa are present. Assuming that their ecological tolerances have changed little in the past 10,000 years, they provide valuable information about the environment of Lake Agassiz. Few of the insects are now found in the region, indicating that the environment has changed. With few exceptions the species present indicate that the climate and vegetation at the time were similar to the present-day climate and vegetation of southeastern Manitoba. The lithology and faunal contents of the sediment are interpreted as follows. Unit A is Late Wisconsinan glacial sediment. Unit B is a lag concentrate formed by wave action during a regressive phase of Lake Agassiz. Unit C is the sediment of a small body of water that formed when the level of Lake Agassiz had dropped below the site. The banks were covered with a spruce forest. Open water gave way to swampy conditions, and unit D was formed. Both units C and D were deposited during the low-water Moorhead Phase of Lake Agassiz. Units E and F are shoreline sediment deposited as the lake level rose, drowning the vegetation. Unit G is modern ditch spoil.

A mammoth (Mammuthus primigenius) tooth from late Wisconsin deposits near Embden, North Dakota, and comments on the distribution of woolly mammoths south of the Wisconsin ice sheets

1986 ◽  
Vol 23 (7) ◽  
pp. 909-918 ◽  
Author(s):  
C. R. Harington ◽  
Allan C. Ashworth
Keyword(s):  
British Columbia ◽  
Continental Shelf ◽  
North Dakota ◽  
Third Molar ◽  
Ice Sheets ◽  
Lake Agassiz ◽  
Mammuthus Primigenius ◽  
Sand And Gravel ◽  
Woolly Mammoth ◽  
Cass County

A well-preserved third molar of a woolly mammoth (Mammuthus primigenius) was recovered from sand and gravel forming the highest (Herman) prominent strandline of Lake Agassiz near Embden in western Cass County, North Dakota. The Herman strandline is estimated to have formed about 11 500 years BP, and presumably the tooth is of similar age. Perhaps the animal lived in a tundra-like area near the Lake Agassiz shoreline.Additional evidence suggests that woolly mammoths occupied a tundra-like range south of the Wisconsin ice sheets extending from southern British Columbia to the Atlantic continental shelf off Virginia.

Portrait préindustriel dans un contexte de grande variabilité naturelle: une étude de cas dans le centre du Québec (Canada)

2011 ◽  
Vol 87 (05) ◽  
pp. 612-624 ◽  
Author(s):  
Eric Alvarez ◽  
Louis Bélanger ◽  
Louis Archambault ◽  
Frédéric Raulier
Keyword(s):  
Temperate Forest ◽  
Forest Cover ◽  
Sustainable Forest Management ◽  
Forest Succession ◽  
Black Spruce ◽  
Spatial Scales ◽  
White Birch ◽  
Industrial Landscape ◽  
Industrial Forest ◽  
Landscape Scales

Pre-industrial forest cover portrait is a recognized method for establishing the bases of sustainable forest management. However, it is a spatially and temporally dependant concept that should be used with caution in presence of big fires. The objective of the study was to portray the pre-industrial landscape in a mixedwood temperate forest in central Quebec at different spatial scales. The study was based on archival records from a forest company. The pre-industrial forest cover landscape of our study area was mainly composed of mature or old-growth (>100 years) stands and dominated by mixedwood forest stands with intolerant hardwoods. The main tree species were white birch, black spruce and jack pine, three species associated to forest succession after fire in the boreal forest. Considering the great variability caused by the fires and partial knowledge of this variability, for each spatial scale considered, we propose some management targets based on the main pre-industrial characteristics of this forest. To respect the pre-industrial variability, our study suggested that silviculture should be adapted at different landscape scales. Cover types and age class targets should be based on main preindustrial characteristics at each landscape scale analyzed.

scholarly journals DRAINAGE OF AN IRRIGATED SALINE SOIL IN ALBERTA

1982 ◽  
Vol 62 (2) ◽  
pp. 387-396
Author(s):  
D. R. BENNETT ◽  
G. R. WEBSTER ◽  
B. A. PATERSON ◽  
D. B. HARKER
Keyword(s):  
Water Table ◽  
Crop Production ◽  
Saline Soil ◽  
Soil Depth ◽  
Drainage System ◽  
High Water ◽  
Coarse Sand ◽  
Irrigation Period ◽  
Dilution Effects ◽  
Sand And Gravel

A shallow subsurface drainage system effectively controlled a high water table and reduced salinity in an irrigated soil near Magrath, Alberta. Plastic corrugated tubing was installed in 1976 at depths of 1.1–1.5 m and spacings of 15 and 30 m in a moderately saline soil. During the irrigation period, the water table rose to within 0.3 m of the surface but was lowered to pre-irrigation levels within 48 h. The water table was maintained at, or below, the depth of the drains between irrigations. The 15- and 30-m spacings of the drain lines were equally effective in providing water table control in this lacustrine soil which was underlain by a coarse sand and gravel layer. Salinity levels were decreased substantially only within the surface 0.3-m soil depth. Quality of the drainage effluent remained constant throughout the growing season with only small dilution effects detected during irrigations. Barley yields increased to 3900 kg/ha in 1978, 2 yr following drainage of this saline soil which had been out of crop production for 20 yr.

How long do trees take to reach breast height after fire in northeastern Ontario?

2002 ◽  
Vol 32 (10) ◽  
pp. 1889-1892 ◽  
Author(s):  
Stan Vasiliauskas ◽  
Han YH Chen
Keyword(s):  
Black Spruce ◽  
Jack Pine ◽  
Growth And Yield ◽  
Site Conditions ◽  
Trembling Aspen ◽  
White Birch ◽  
Study Objective ◽  
Stand Establishment ◽  
Breast Height ◽  
Fire Origin

Accurate determination of stand establishment ages is important in developing growth and yield models and in studying stand dynamics of fire-origin stands. The study objective was to determine time to reach breast height for black spruce (Picea mariana (Mill.) BSP), jack pine (Pinus banksiana Lamb.), trembling aspen (Populus tremuloides Michx.), and white birch (Betula papyrifera Marsh.) from fire origin stands under different site conditions in northeastern Ontario. Stands were randomly selected from burns with known fire dates. In each stand, three to six dominant and codominant trees of a selected species were cored at breast height (1.3 m above the ground level) to determine time to reach breast height. Trembling aspen and white birch did not differ for time to reach breast height after fire, taking 6 or 7 years, jack pine took marginally longer (8 years), whereas black spruce took the longest (18 years). While time to reach breast height did not vary among site conditions as described by soil texture and moisture regime, it was positively related to time since fire. The results of this study indicate that stand establishment dates and total tree ages can be substantially underestimated if breast height age is used as the stand age, resulting in misinterpretations of growth and yield and forest succession.

Glyphosate efficacy on eastern Canadian forest weeds. Part II: deposit–response relationships and crop tolerance

1992 ◽  
Vol 22 (8) ◽  
pp. 1160-1171 ◽  
Author(s):  
D. G. Pitt ◽  
R. A. Fleming ◽  
D. G. Thompson ◽  
E. G. Kettela
Keyword(s):  
Black Spruce ◽  
Weather Conditions ◽  
Post Treatment ◽  
Red Maple ◽  
White Birch ◽  
Crown Area ◽  
Crop Tolerance ◽  
Area Reduction ◽  
Application Systems ◽  
Four Blocks

First-season herbicide efficacy and crop tolerance results are presented for a range of glyphosate (VISION®) rates (0–1.00 kg acid equivalent per hectare) aerially applied with two different dispersal systems (AU5000 Micronairs® and conventional hydraulic nozzles). Derivative-free nonlinear regression was used to model post-treatment raspberry cover (Rubusidaeus L. var. strigosus (Michx.) Maxim.) as an exponentially decreasing function of chemical deposit (R2 = 0.87). Similar methods were used to model post-treatment crown area as a function of chemical deposit and pretreatment crown area for pin cherry (Prunuspensylvanica L.f.) (R2 = 0.92), red maple (Acerrubrum L.) (R2 = 0.79), white birch (Betulapapyrifera Marsh.) (R2 = 0.93), elderberry (Sambucuspubens Michx.) (R2 = 0.85), and aspen (Populustremuloides Michx.) (R2 = 0.96). Acceptable first-season control (>60% cover reduction) of raspberry, pin cherry, elderberry, and aspen was achieved with rates of deposit ≥0.50 kg acid equivalent per hectare. Red maple and white birch crown area reduction averaged 60% at the highest rate tested (1 kg acid equivalent per hectare). Significant differences in efficacy attributable to the different dispersal systems were found only for pin cherry: the Micronair system resulted in 30% greater efficacy on one of the four blocks tested (P < 0.0001). On this particular block, characterized by unstable weather conditions during treatment, both systems produced significantly greater efficacy than observed on the other blocks for all species studied except aspen (P < 0.01). No significant differences were detected in black spruce (Piceamariana (Mill.) B.S.P.) health patterns in areas treated with the two different application systems (P = 0.780). Crop trees in untreated areas declined in health relative to trees in treated areas (P < 0.001).

Total belowground carbon and nitrogen partitioning of mature black spruce displaying genetic × soil moisture interaction in growth

2012 ◽  
Vol 42 (11) ◽  
pp. 1939-1952 ◽  
Author(s):  
John E. Major ◽  
Kurt H. Johnsen ◽  
Debby C. Barsi ◽  
Moira Campbell
Keyword(s):  
Fine Roots ◽  
Root Biomass ◽  
Black Spruce ◽  
Soil Depth ◽  
C Sequestration ◽  
Nitrogen Partitioning ◽  
Coarse Roots ◽  
Soil C ◽  
Coarse Root ◽  
C And N

Total belowground biomass, soil C, and N mass were measured in plots of 32-year-old black spruce ( Picea mariana (Mill.) Britton, Sterns & Poggenb.) from four full-sib families studied previously for drought tolerance and differential productivity on a dry and a wet site. Stump root biomass was greater on the wet than on the dry site; however, combined fine and coarse root biomass was greater on the dry than on the wet site, resulting in no site root biomass differences. There were no site differences in root distribution by soil depth. Drought-tolerant families had greater stump root biomass and allocated relatively less to combined coarse and fine roots than drought-intolerant families. Fine roots (<2 mm) made up 10.9% and 50.2% of the belowground C and N biomass. Through 50 cm soil depth, mean total belowground C mass was 187.2 Mg·ha–1, of which 8.9%, 3.4%, 0.7%, and 87.0% were from the stump root, combined fine and coarse roots, necromass, and soil, respectively. Here, we show that belowground C sequestration generally mirrors (mostly from stump roots) aboveground growth, and thus, trends in genetic and genetic × environment productivity effects result in similar effects on belowground C sequestration. Thus, tree improvement may well be an important avenue to help stem increases in atmospheric CO2.

Reproduction de l'épinette noire (Piceamariana) après coupe à blanc de superficie réduite

1977 ◽  
Vol 7 (4) ◽  
pp. 648-655 ◽  
Author(s):  
Gilles Frisque ◽  
P. E. Vézina
Keyword(s):  
Boreal Forest ◽  
Black Spruce ◽  
Critical Factor ◽  
White Birch ◽  
Coupe À Blanc ◽  
Made In

Small clear-cuttings (elliptical, circular, and strip) were made in the commercial boreal forest in Quebec to improve black spruce (Piceamariana (Mill.) B.S.P.) reproduction.Five years after cutting, black spruce layers were as numerous as black spruce seedlings and total softwood reproduction averaged 26 710 stems per hectare (10 810 stems per acre) with 90% stocking. In some cases, white birch stems tripled between the 1st and 5th year after cutting, which may have an important effect on stand composition.Strip cuts gave more stems per hectare than circular or elliptical cuts but stocking was lower. Strips 40 m wide (130 ft) gave better results than those 80 m wide (260 ft).Stocking, although adequate in all these small clear-cuttings, appears to be a more critical factor in the success of softwood reproduction than is density.

scholarly journals White spruce enrichment planting in boreal mixedwoods as influenced by localized site preparation: 11-year update

2020 ◽  
Vol 96 (01) ◽  
pp. 27-35
Author(s):  
Myriam Delmaire ◽  
Nelson Thiffault ◽  
Evelyne Thiffault ◽  
Julie Bouliane
Keyword(s):  
Picea Glauca ◽  
Native Species ◽  
Black Spruce ◽  
Abies Balsamea ◽  
Basal Area ◽  
White Spruce ◽  
Site Preparation ◽  
White Birch ◽  
Ecosystem Based Management ◽  
Enrichment Planting

Ecosystem-based management aims to maintain the natural proportion of native species over a given landscape. White spruce (Picea glauca (Moench) Voss) is a species sensitive to environmental conditions; it is especially demanding in terms of nutrients and its regeneration is negatively affected by clearcut harvesting. Its proportion is now significantly lower than what it was in the preindustrial forests of Québec (Canada). As a native species in boreal Québec, efforts to maintain its proportion in the landscape are undertaken for white spruce, but little is known about the best practices to maximize establishment success of seedlings planted in the balsam fir (Abies balsamea)–white birch (Betula papyrifera) bioclimatic domain. Our general objective was to identify planting practices as related to microsite treatment that favour white spruce sapling survival and size after 11 growing seasons following enrichment planting of sites harvested by mechanized careful logging in an ecosystem-based management context. We also aimed at comparing white spruce performance with that of black spruce (Picea mariana (Mill.) BSP), a native species that is less sensitive to abiotic stress. Finally, we wanted to assess stand composition at this juvenile stage, as a function of microsite treatment and planted species. Localized site preparation did not significantly affect growth or survival for white spruce compared to control conditions. Furthermore, localized site preparation did not increase the proportion of white and black spruce, as evaluated by basal area. Our results suggest that white spruce can be successfully established in enrichment planting in fir-dominated boreal forests, without site preparation.

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