Late Holocene solifluction lobe activity in the Mount Rae area, southern Canadian Rocky Mountains

1987 ◽  
Vol 24 (8) ◽  
pp. 1634-1642 ◽  
Author(s):  
Daniel J. Smith
Keyword(s):  
Residence Time ◽  
Mean Residence Time ◽  
Rocky Mountains ◽  
Late Holocene ◽  
The Other ◽  
Canadian Rocky Mountains ◽  
Mass Wasting ◽  
Canadian Rockies

Solifluction lobes are tongue-shaped accumulations of sediment resulting from localized periglacial mass wasting. Radiocarbon records from beneath two turf-banked lobes in the Mount Rae area of the southern Canadian Rockies indicate that solifluction processes have been continuously active for at least the last 2000 years. The long-term rates of frontal movement at both sites average 0.49 cm/year, but vary in magnitude from 0.35 to 1.50 cm/year.Both lobes terminate above soil pedons progressively overridden by their advance. Estimates of the apparent mean residence time of the contemporary soil ranges from 962 ± 100 years in one case to 1600 ± 100 years in the other. This information was used to reconstruct a chronology of lobe activity. Collectively, the radiocarbon records indicate that solifluction lobes in this area were advancing quite rapidly between 1900–1750 years BP but declined to a much slower, but relatively constant, pace up until the present.

Nucleation during primary succession in the Canadian Rockies

1993 ◽  
Vol 71 (8) ◽  
pp. 1093-1096 ◽  
Author(s):  
D. J. Blundon ◽  
D. A. MacIsaac ◽  
M. R. T. Dale
Keyword(s):  
British Columbia ◽  
Nitrogen Fixation ◽  
Key Words ◽  
Rocky Mountains ◽  
Primary Succession ◽  
The Other ◽  
Pioneer Species ◽  
Canadian Rocky Mountains ◽  
Successional Species ◽  
Key Words Colonization

A study of nucleation during primary succession was carried out on age sequences of communities at two sites in the Canadian Rocky Mountains: one at the Mount Robson moraines, British Columbia, the other at Southeast Lyell Glacier, Alberta. The study concentrated on the associations of species with the nitrogen-fixing plants Hedysarum boreale var. mackenzii at Mount Robson moraines and Dryas drummondii at Southeast Lyell Glacier because those plants might serve as nuclei for colonization by other species, thus facilitating succession. The data show that recruitment of later successional species is greater in patches of the two pioneer species, but the fact that recruitment takes place away from the plants also suggests that although there is nucleation, it is not necessary for succession at these sites. Key words: colonization, nitrogen fixation, nucleation, succession.

scholarly journals VII.—The Canadian Rockies. Part I : On a Collection of Middle Cambrian Fossils obtained by Edward Whymper, Esq., F.R.G.S., from Mount Stephen, British Columbia

1902 ◽  
Vol 9 (11) ◽  
pp. 502-505 ◽  
Author(s):  
Henry Woodward
Keyword(s):  
British Columbia ◽  
Rocky Mountains ◽  
Canadian Rocky Mountains ◽  
Canadian Rockies ◽  
Middle Cambrian ◽  
Pacific Railroad ◽  
Northern Side

In the Summer of 1901 my friend Mr. Edward Whymper, the well-known traveller, mountain explorer, and writer, paid a visit to the watershed of the Canadian Rocky Mountains, and during a stay at Field, the highest pass reached on the Canadian and Pacific Railroad, he examined the slopes of Mount Stephen, and at a height of 6,000 feet on its northern side found numerous Trilobites, and brought home a considerable collection.

scholarly journals Long-term steady state <sup>13</sup>C labelling to investigate soil carbon turnover in grasslands

2007 ◽  
Vol 4 (3) ◽  
pp. 385-394 ◽  
Author(s):  
K. Klumpp ◽  
J. F. Soussana ◽  
R. Falcimagne
Keyword(s):  
Organic Matter ◽  
Steady State ◽  
Soil Organic Matter ◽  
Soil Carbon ◽  
Residence Time ◽  
Particulate Organic Matter ◽  
Mean Residence Time ◽  
Carbon Turnover ◽  
13C Labelling

Abstract. We have set up a facility allowing steady state 13CO2 labeling of short stature vegetation (12 m2) for several years. 13C labelling is obtained by scrubbing the CO2 from outdoors air with a self-regenerating molecular sieve and by replacing it with 13C depleted (−34.7±0.03‰) fossil-fuel derived CO2 The facility, which comprises 16 replicate mesocosms, allows to trace the fate of photosynthetic carbon in plant-soil systems in natural light and at outdoors temperature. This method was applied to the study of soil organic carbon turnover in temperate grasslands. We tested the hypothesis that a low disturbance by grazing and cutting of the grassland increases the mean residence time of carbon in coarse (>0.2 mm) soil organic fractions. Grassland monoliths (0.5×0.5×0.4 m) were sampled from high and low disturbance treatments in a long-term (14 yrs) grazing experiment and were placed during two years in the mesocosms. During daytime, the canopy enclosure in each mesocosm was supplied in an open flow with air at mean CO2 concentration of 425 µmol mol−1 and δ13C of −21.5±0.27‰. Fully labelled mature grass leaves reached a δ13C of −40.8 (±0.93) and −42.2‰ (±0.60) in the low and high disturbance treatments, respectively, indicating a mean 13C labelling intensity of 12.7‰ compared to unlabelled control grass leaves. After two years, the delta 13C value of total soil organic matter above 0.2 mm was reduced in average by 7.8‰ in the labelled monoliths compared to controls. The isotope mass balance technique was used to calculate for the top (0–10 cm) soil the fraction of 13C labelled carbon in the soil organic matter above 0.2 mm (i.e. roots, rhizomes and particulate organic matter). A first order exponential decay model fitted to the unlabelled C in this fraction shows an increase in mean residence time from 22 to 31 months at low compared to high disturbance. A slower decay of roots, rhizomes and particulate organic matter above 0.2 mm is therefore likely to contribute to the observed increased in soil carbon sequestration in grassland monoliths exposed to low disturbance.

scholarly journals Human history and palaeoenvironmental change at Site 17, Freshwater Beach, Lizard Island, northeast Queensland, Australia

2013 ◽  
Vol 16 ◽  
pp. 141 ◽  
Author(s):  
Carol J. Lentfer ◽  
Matthew W. Felgate ◽  
Robynne A. Mills ◽  
Jim Specht
Keyword(s):  
Intertidal Zone ◽  
Late Holocene ◽  
The Other ◽  
Eastern Coast ◽  
Human History ◽  
Palaeoenvironmental Change ◽  
Lizard Island ◽  
Reef Islands ◽  
The Relationship

Late Holocene patterns of change in occupation and use of islands along the eastern coast of Queensland have long been debated in terms of various drivers, though much of this discussion relates to regions south of Cairns, with comparatively little study of the far northern Great Barrier Reef islands. The numerous middens, stone arrangements and art sites on Lizard Island suggest long-term use by Indigenous people, but recent discoveries of pottery give tantalising glimpses of a prehistoric past that may have included a prehistoric economy involving pottery. Here we review previous archaeological surveys and studies on Lizard Island and report on new archaeological and palaeoenvironmental studies from the Site 17 midden at Freshwater Beach, with an oldest date of 3815–3571 cal BP. We identify two major changes in the archaeological and palaeoenvironmental records, one associated with more recent European influences and the other at c.2000 cal BP. Pottery from the intertidal zone is as yet undated. When dates become available the relationship between the Site 17 results reported here and the use of pottery on the island may be clarified.

Macgowanella gen. nov., possible bryozoan holdfasts, Mississippian of southern Canadian Rocky Mountains, Alberta

1980 ◽  
Vol 17 (10) ◽  
pp. 1431-1435 ◽  
Author(s):  
Samuel J. Nelson ◽  
Thomas E. Bolton
Keyword(s):  
Rocky Mountains ◽  
New Genus ◽  
Canadian Rocky Mountains ◽  
Canadian Rockies ◽  
Incertae Sedis

Well-preserved, enigmatic and striking, partially interlocking slender star-like structures from the Mississippian of the southern Canadian Rockies are incertae sedis, but may possibly be bryozoan holdfasts. They represent a new genus, Macgowanella, and belong to species previously referred to Evactinopora? tenuiradiata Warren and E.? stellata Warren.

scholarly journals Seasonal and Interannual Variability of Melt-Season Albedo at Haig Glacier, Canadian Rocky Mountains

2020 ◽  
Author(s):  
Shawn J. Marshall ◽  
Kristina Miller
Keyword(s):  
Mass Balance ◽  
Interannual Variability ◽  
Rocky Mountains ◽  
Glacier Mass Balance ◽  
Weather Station ◽  
Canadian Rocky Mountains ◽  
Degree Day ◽  
Mass Balance Models ◽  
Glacier Ice

Abstract. In situ observations of summer albedo are presented for the period 2002–2017 from Haig Glacier in the Canadian Rocky Mountains. The observations provide insight into the seasonal evolution and interannual variability of snow and ice albedo, including the effects of summer snowfall, the decay of snow albedo through the melt season, and the potential short-term impacts of regional wildfire activity on ice albedo reductions. Mean summer albedo (&amp;pm;1σ) recorded at an automatic weather station in the upper ablation zone of the glacier was αS = 0.55 &amp;pm; 0.07 over this period, with no evidence of long-term albedo trends. Each summer the surface conditions at the weather station undergo a transition from a dry, reflective springsnowpack (αS ∼ 0.8), to a wet, homogeneous mid-summer snowpack (αS ∼ 0.5), to exposed, impurity-rich glacier ice, with ameasured albedo of 0.21 &amp;pm; 0.06 over the study period. The ice albedo drops to ~ 0.1 during years of intense regional wildfire activity such as 2003 and 2017, but it recovers from this in subsequent years. Summer snowfall events have a significant influence on albedo, and a stochastic parameterization of these events is shown to improve modelled estimates of summer albedo and mass balance. Modifications to conventional degree-day melt factors are also suggested, to better capture the effects of seasonal albedo evolution in climate, hydrology, and glacier mass balance models that use temperature index or positive-degree day methods.

II.—The Canadian Rockies. Part II: On some Rock-specimens collected by E. Whymper, Esq., F.R.S.E., in the Canadian Rocky Mountains

1902 ◽  
Vol 9 (12) ◽  
pp. 544-550
Author(s):  
T. G. Bonney
Keyword(s):  
Rocky Mountains ◽  
Canadian Rocky Mountains ◽  
Canadian Rockies ◽  
Eastern Side ◽  
North East ◽  
The North ◽  
Southern Side ◽  
Rock Specimens

The Canada Pacific Railway crosses the watershed of the Rocky Mountains at Hector or, as it is sometimes called, Kicking Horse Pass, and the specimens brought back by Mr. Whymper represent a district extending for some twenty miles on each side of the track, either on or west of the divide. The first group was obtained from summits lying near the railway on its southern side. Of these Mount Whyte is about three miles from it on the divide, which is crossed by Pope's Col just to the north of that summit, and about a mile to the north-east of the latter rises Mount St. Piran. About 3½ miles south of Mount Whyte, Mitre Col leads from the Lefroy to the Horseshoe glacier, between Mount Lefroy, which is on the divide, and Mitre Peak on the eastern side of it.

Radioimmunotherapy for treatment of acute myeloid leukaemia and myelodysplastic syndrome

2005 ◽  
Vol 44 (03) ◽  
pp. 107-117
Author(s):  
R. G. Meyer ◽  
W. Herr ◽  
A. Helisch ◽  
P. Bartenstein ◽  
I. Buchmann
Keyword(s):  
Acute Myeloid Leukaemia ◽  
Myeloid Leukaemia ◽  
Primary Tumour ◽  
The Other ◽  
Haematopoietic Stem Cell ◽  
Other Hand ◽  
Primary Reduction ◽  
The One ◽  
Acute Myeloid

SummaryThe prognosis of patients with acute myeloid leukaemia (AML) has improved considerably by introduction of aggressive consolidation chemotherapy and haematopoietic stem cell transplantation (SCT). Nevertheless, only 20-30% of patients with AML achieve long-term diseasefree survival after SCT. The most common cause of treatment failure is relapse. Additionally, mortality rates are significantly increased by therapy-related causes such as toxicity of chemotherapy and complications of SCT. Including radioimmunotherapies in the treatment of AML and myelodyplastic syndrome (MDS) allows for the achievement of a pronounced antileukaemic effect for the reduction of relapse rates on the one hand. On the other hand, no increase of acute toxicity and later complications should be induced. These effects are important for the primary reduction of tumour cells as well as for the myeloablative conditioning before SCT.This paper provides a systematic and critical review of the currently used radionuclides and immunoconjugates for the treatment of AML and MDS and summarizes the literature on primary tumour cell reductive radioimmunotherapies on the one hand and conditioning radioimmunotherapies before SCT on the other hand.

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