POPULATION DYNAMICS OF THE LODGEPOLE NEEDLE MINER, RECURVARIA STARKI FREEMAN, IN CANADIAN ROCKY MOUNTAIN PARKS

1959 ◽  
Vol 37 (6) ◽  
pp. 917-943 ◽  
Author(s):  
R. W. Stark
Keyword(s):  
Climatic Factors ◽  
Rocky Mountain ◽  
Warming Trend ◽  
Western Canada ◽  
Canadian Rocky Mountains ◽  
Control Factors ◽  
Egg Formation ◽  
Northern Latitudes ◽  
Winter Temperatures ◽  
Larval Establishment

The lodgepole needle miner, Recurvaria starki Freeman, has been studied intensively since 1948. Life tables, survival, and death-rate curves show clearly that there are five periods in the 2-year life cycle of the needle miner during which extensive mortality may occur: (1) between egg formation and oviposition; (2) between oviposition and larval establishment; (3) during the first larval hibernation; (4) during the second larval hibernation; (5) during the spring of moth emergence. Population success is also undoubtedly affected by conditions during the adult life.Population sampling has shown that the outbreak has declined since 1948. Defoliation and increment studies have shown that the period of greatest defoliation occurred from 1940 to 1944 and that the outbreak probably began in the late 1930's. The major cause of the decline was severe winter temperatures, probably during the coldest month. Parasitism was not an important factor in the outbreak decline, apparently because it was controlled in the same manner as the host, by winter temperatures. Other natural control factors are discussed as well as the possible effects of climatic factors on oviposition and fecundity.A detailed survey of weather records since 1920 and yearly averages since 1885 suggest that release of the needle miner population was due to a warming trend in the climate of western Canada. This trend began in the late 1930's, reached a peak in the mid-1940's, and has declined since that time. The warming trend in northern latitudes has been noted by other authors and is substantiated by weather records of this region. It is further postulated that the climate of the Canadian Rocky Mountains is generally too severe for an outbreak of the lodgepole needle miner to be prolonged.

Geographic patterns of genetic variation and population structure in Pinus aristata, Rocky Mountain bristlecone pine

2012 ◽  
Vol 42 (1) ◽  
pp. 23-37 ◽  
Author(s):  
Anna W. Schoettle ◽  
Betsy A. Goodrich ◽  
Valerie Hipkins ◽  
Christopher Richards ◽  
Julie Kray
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Bark Beetles ◽  
Climatic Factors ◽  
Rocky Mountain ◽  
Conservation Strategies ◽  
Restricted Gene Flow ◽  
Populations At Risk ◽  
Bristlecone Pine ◽  
Pinus Aristata

Pinus aristata Engelm., Rocky Mountain bristlecone pine, has a narrow core geographic and elevational distribution, occurs in disjunct populations, and is threatened by rapid climate change, white pine blister rust, and bark beetles. Knowledge of genetic diversity and population structure will help guide gene conservation strategies for this species. Sixteen sites across four mountain ranges in the core distribution of P. aristata were sampled and genetic diversity was assessed with 21 isozyme loci. Low species and population level genetic diversity (He = 0.070 and 0.062, respectively) occurred with moderate among-population differentiation (FST = 0.131). Genetic diversity correlated with longitude, latitude, and elevation and a strong mountain island effect may contribute to substructuring and isolation. Using multiple complementary analyses, sampled trees were assigned to three genetic lineages that varied in diversity and admixture and were associated with different climatic factors. The distribution of genetic diversity and substructuring of P. aristata may be an outcome of a combination of restricted gene flow due to geographic and phenological isolation, random processes of genetic drift, life history traits, natural selection, and postglacial migrations. The combination of low genetic diversity, moderate population isolation, and a protracted regeneration dynamic puts populations at risk for extirpation by novel stresses.

Studies on the origin, evolution and distribution of the Gramineae. I. The tribe Andropogoneae

1958 ◽  
Vol 6 (2) ◽  
pp. 116 ◽  
Author(s):  
W Hartley
Keyword(s):  
Climatic Factors ◽  
Western Hemisphere ◽  
Western India ◽  
High Concentration ◽  
Cytological Evidence ◽  
Origin And Evolution ◽  
Eastern Hemisphere ◽  
Winter Temperatures ◽  
The Tropics ◽  
World Distribution

From a study of the grass flora of some 300 regions, a world distribution map of the grass tribe, Andropogoneae, has been prepared. This map shows that the Indo-Malaysian region is relatively rich in species of the tribe, with zones of high concentration in western India and in southern Indonesia. The relative species density falls off rapidly in passing from the tropical to the temperate zones, and is lower in the western than in the eastern hemisphere. Climatic factors are of major importance in determining the distribution pattern. Winter temperatures are of special significance in temperate regions, while there is a striking relationship between high midsummer rainfall and relative abundance of species of Andropogoneae in the tropics and subtropics. In general, the geographical survey supports conclusions drawn from taxonomic and cytological evidence regarding the origin and evolution of the tribe, but with greater emphasis on climate as a significant factor. The Andropogoneae have had a long evolutionary history in the eastern hemisphere, but have spread more recently to the western hemisphere, where they have not yet attained their full development.

THE ROCKY MOUNTAIN TRENCH: A PROBLEM

1964 ◽  
Vol 1 (3) ◽  
pp. 184-205 ◽  
Author(s):  
C. H. Crickmay
Keyword(s):  
Rocky Mountains ◽  
Rocky Mountain ◽  
Canadian Rocky Mountains ◽  
The West ◽  
West Side ◽  
Combined Action ◽  
Headward Erosion

The Rocky Mountain Trench is defined as the 1 000-mile valley which marks the west side of the Canadian Rocky Mountains. The background of the Trench as a problem is examined, and descriptions, geographical and geological, are given. Previous work on Trench origin is reviewed and note is taken of the seeming inapplicability of accepted erosion theories to the making of the erosion-made Trench. An hypothesis is offered in which the combined action of drainage hemmed in by bordering uplifts, guided headward erosion, lateral corrasion, and streams repeatedly reversed by continuing diastrophism is suggested as the excavator of the Trench, a valley characterized by the puzzling peculiarity of continuous depth without a consistent gradient.

Effect of latitude on narrow-leaved purple coneflower (Echinacea angustifolia DC.) yield and phytochemical quality

2020 ◽  
Vol 100 (1) ◽  
pp. 103-112
Author(s):  
Ian R. Willick ◽  
Branka Barl ◽  
Karen K. Tanino
Keyword(s):  
Chlorogenic Acid ◽  
Acid Content ◽  
Western Canada ◽  
Root Yield ◽  
Field Site ◽  
Echinacea Angustifolia ◽  
Phytochemical Content ◽  
Purple Coneflower ◽  
Cash Crops ◽  
Northern Latitudes

The worldwide increase in demand for plant-derived drugs has increased interest in medicinal plants as alternative cash crops across western Canada. The objective of this research was to determine if the Northern Vigor® phenomenon, expressed as a combination of elevated crop yield and phytomedicinal quality in crops grown in northern latitudes, exists in narrow-leaved purple coneflower (Echinacea angustifolia DC.). In a 2-yr study, narrow-leaved purple coneflower was grown in three field sites in Saskatchewan, Canada (SK; Saskatoon, La Ronge, and Outlook) and one field site in Oregon, United States (Madras), to test the effects of latitude on root yield, phenolic, and alkylamide phytochemical markers. Roots harvested in 1999 (all three SK sites) and 2000 (two SK sites) had higher root biomass compared with roots harvested in Oregon. Root echinacoside and cynarin content were significantly higher in both years in the three Saskatchewan sites compared with Madras, whereas root chlorogenic acid content and total alkylamides were significantly higher in all three Saskatchewan sites in 1999. In 2000, root chlorogenic acid content and total alkylamides were higher in two of the three Saskatchewan sites compared with Madras. While Aster Yellows were prevalent in Echinacea in Saskatchewan, this disease did not significantly decrease root yield phenolic or phytochemical content. These data suggest that Saskatchewan has a competitive advantage in producing premium-quality narrow-leaved purple coneflower root in North America.

Study of Long Combination Vehicles on Two-Lane Highways

1998 ◽  
Vol 1613 (1) ◽  
pp. 43-49 ◽  
Author(s):  
Raymond A. Barton ◽  
John Morrall
Keyword(s):  
High Speed ◽  
Rocky Mountain ◽  
Highway Safety ◽  
Level Of Service ◽  
Western Canada ◽  
Maximum Volume ◽  
Vehicle Type ◽  
Heavy Trucks ◽  
Traffic Volumes ◽  
Council Of Ministers

In 1988, the Council of Ministers of Transportation and Highway Safety in Canada endorsed a memorandum of understanding designed to improve uniformity between provinces and territories. The regulations covering weights and dimensions for tractor-semitrailers and double combination trucks specified a maximum length of 23 m. However, in western Canada, which includes the provinces of British Columbia, Alberta, Saskatchewan, and Manitoba, a maximum vehicle length of 25 m was adopted. Vehicles longer than 25 m are generally referred to as long combination vehicles (LCVs) and include the following vehicles: triple trailer combinations, 35 m in length; Rocky Mountain doubles, 30 m in length; log haul trucks, which can be up to 30.5 m in length; and turnpike doubles, 38 m in length. A study was conducted to develop recommendations relating to the use of LCVs on two-lane highways in Alberta. The basic approach was to examine the incremental impact of LCV-type vehicles on two-lane highway operations compared with a baseline vehicle type, namely, 25-m standard double heavy trucks. Although the study of LCVs examined a range of issues that included low- and high-speed offtracking, and aerodynamic buffeting, only the findings related to traffic volume criteria are presented. The main recommendation with respect to passing opportunities and level of service was the development of maximum traffic volumes for two-lane highways with and without passing lanes and with a given percentage of passing zones. The main criteria are to ensure that a net passing opportunity of at least 30 percent is provided to drivers impeded by LCVs. This is roughly comparable to providing to Level of Service C. For example, the maximum volume below which Rocky Mountain doubles may operate on a two-lane highway is 425 veh/h for a section with 100 percent passing zones. If 2-km passing lanes are provided every 10 km, Rocky Mountain doubles could operate at traffic volumes up to 734 veh/h and still ensure a net passing opportunity of 30 percent.

Coccidia of Rocky Mountain bighorn sheep in Western Canada

1971 ◽  
Vol 49 (11) ◽  
pp. 1461-1464 ◽  
Author(s):  
Leslie S. Uhazy ◽  
Jerome L. Mahrt ◽  
John C. Holmes
Keyword(s):  
British Columbia ◽  
National Park ◽  
Rocky Mountain ◽  
Bighorn Sheep ◽  
Western Canada ◽  
Fecal Samples

A survey of coccidia in the Rocky Mountain bighorn sheep (Ovis. c. canadensis) in Alberta and Kootenay National Park, British Columbia, was conducted from the winter of 1967 to the spring of 1969. Ninety percent of 510 fecal samples examined were positive for coccidia. The species recovered, in order of prevalence, were Eimeria ovina (syn., E. arloingi) (56%), E. parva (35%), E. crandallis (34%), E. ahsata (33%), E. ninakohlyakimovae (19%), E. faurei (6%), E. intricata (5%) and E. granulosa (1%). Coccidiosis was not encountered in the field; however, evidence which suggests the magnitude of pathogenic infections is presented.

scholarly journals Effects of needleleaf forest cover on radiation and snowmelt dynamics in the Canadian Rocky Mountains

2011 ◽  
Vol 41 (3) ◽  
pp. 608-620 ◽  
Author(s):  
C. R. Ellis ◽  
J. W. Pomeroy ◽  
R. L.H. Essery ◽  
T. E. Link
Keyword(s):  
Forest Cover ◽  
Longwave Radiation ◽  
Rocky Mountain ◽  
Shortwave Radiation ◽  
Mountain Forest ◽  
Spruce Forest ◽  
Total Radiation ◽  
Canadian Rocky Mountains ◽  
Forest Sites ◽  
Extensive Field

Radiation is the main energy source for snowpack warming and melt in mountain needleleaf forests, and runoff from these forests is the main contributor to spring river flows in western North America. Utilizing extensive field observations, the effect of needleleaf forest cover on radiation and snowmelt timing was quantified at pine and spruce forest sites and nearby clearings of varying slope and aspect in an eastern Canadian Rocky Mountain headwater basin. Compared with open clearing sites, shortwave radiation was much reduced under forest cover, resulting in smaller differences in melt timing between forested slopes relative to open slopes with different aspects. In contrast, longwave radiation to snow was substantially enhanced under forest cover, especially at the dense spruce forest sites where longwave radiation dominated total energy for snowmelt. In both pine and spruce environments, forest cover acted to substantially reduce total radiation to snow and delay snowmelt timing on south-facing slopes while increasing total radiation and advancing snowmelt timing on north-facing slopes. Results strongly suggest that impacts on radiation to snow and snowmelt timing from changes in mountain forest cover will depend much on the slope and aspect at which changes occur.

Conductive structures under the Canadian Rocky Mountains

1985 ◽  
Vol 22 (3) ◽  
pp. 384-398 ◽  
Author(s):  
D. K. Bingham ◽  
D. I. Gough ◽  
M. R. Ingham
Keyword(s):  
Rocky Mountains ◽  
Transfer Functions ◽  
Three Dimensional ◽  
Vertical Component ◽  
Rocky Mountain ◽  
Auroral Zone ◽  
Event Analysis ◽  
Canadian Rocky Mountains ◽  
Period Range ◽  
Single Station

The paper reports results from an array of 33 three-component magnetometers that recorded time-varying fields in 1981 over an area of some 56 000 km2 in the Canadian Cordillera. The array was centred at Tête Jaune Cache in the Rocky Mountain Trench, where a large magnetovariation anomaly had been located in an earlier array study. It was bisected by the trench and extended to the northeast across the Rocky Mountains to the Alberta Foothills and to the southwest across the Cariboo and Monashee mountains. Magnetograms and Fourier transform maps covering the period range 10–91 min show strong attenuation of the vertical component, Z, southwest of the Rocky Mountain Trench, with very large Z amplitudes in the Main Ranges of the Rockies. The horizontal components show an elongated anomaly along the Rocky Mountains Main Ranges and Trench, with three-dimensional features superimposed. The conductive structures include a highly conductive layer, probably in the lower crust, southwest of the trench and a conductive ridge rising into the upper crust near the edge of that layer. Current models have been fitted to observed vertical -and horizontal-component anomalies and show that both layer and ridge are necessary for a fit and that the ridge is 50–80 km wide. Single-station transfer functions at periods of 10 and 22 min have been calculated from a number of variation events of various polarizations, to reduce any displacement of the anomalies by auroral-zone source currents. Artificial-event analysis, with these transfer functions, shows that the conductive ridge lies under the Main Ranges of the Rockies and not under the trench. Its great width indicates a structure of major tectonic significance, which will be considered in another paper.

scholarly journals A 333-year record of the mean minimum temperature reconstruction in the Western Tianshan Mountains, China

2019 ◽  
Vol 46 (1) ◽  
pp. 37-48 ◽  
Author(s):  
Liang Jiao ◽  
Shengjie Wang ◽  
Yuan Jiang ◽  
Xuerui Liu
Keyword(s):  
Minimum Temperature ◽  
Large Scale ◽  
Climatic Factors ◽  
Moving Average ◽  
Temperature Reconstruction ◽  
Warming Trend ◽  
Limiting Factor ◽  
Western Tianshan ◽  
The Mean ◽  
The Relationship

Abstract In this paper, a fragile ecological area in the Western Tianshan National Nature Reserve of China was selected as the research region, and Picea schrenkiana, which is sensitive to climate change, was selected as the research object. The mean minimum temperature in the growing season of the previous year (May to September) was the main limiting factor for tree radial growth based on an analysis of the relationship between chronological series and climatic factors during 1959–2012 (r = –0.792, p < 0.05). Moreover, the relationship was stable, which showed that tree rings can be used as alternative materials for climate reconstruction. Therefore, the mean minimum temperature of the previous year in 1680–2012 was reconstructed, and the explained variance of the reconstruction equation was 62.7% (R2adj = 62.0%, F = 85.8). The 31 dramatically altered years were found via characteristic year analyses, and extreme changes occurred most often under relatively warm conditions. The mean minimum temperature in the reconstruction shows a clear warming trend by the 11-year moving average of the reconstructive series since the 1950s (the temperature increase: 0.341°C/decade). The driving factors of the mean minimum temperature were influenced mainly by the interaction of solar activity and large-scale atmospheric–oceanic variability, especially the westerly circulations.

scholarly journals Distribution of a New Invasive Species, Sipha maydis (Heteroptera: Aphididae), on Cereals and Wild Grasses in the Southern Plains and Rocky Mountain States

2019 ◽  
Vol 112 (4) ◽  
pp. 1713-1721
Author(s):  
Gary J Puterka ◽  
Robert W Hammon ◽  
Melissa Franklin ◽  
Dolores W Mornhinweg ◽  
Tim Springer ◽  
...  
Keyword(s):  
United States ◽  
Host Range ◽  
Rocky Mountain ◽  
The United States ◽  
Grass Species ◽  
New Host ◽  
Southern Plains ◽  
Wide Range ◽  
Winter Temperatures ◽  
Sorghum Production

Abstract Sipha maydis Passerini (Heteroptera: Aphididae) is a cereal pest with an extensive geographical range that includes countries in Europe, Asia, Africa, and South America. Reports of S. maydis in the United States have been infrequent since it was first detected in California, 2007. Two studies, focused (NW CO) and multistate (OK, TX, NM, CO, UT, WY), were conducted to determine the distribution and host range of S. maydis in the Rocky Mountain and Southern Plains states over a 3-yr period, 2015–2017. In 2015, focused sampling in NW Colorado found S. maydis at 59% of the 37 sites, primarily on wheat. Sipha maydis did not survive extreme winter temperatures from late December 2015 to early January 2016 that ranged from −9.0 to −20.9°C over a 9-d period, which resulted in no aphids detected in 2016. In the multistate study, S. maydis occurred in 14.6% of 96 sites sampled in 2015, 8% of 123 sites in 2016, and 9% of 85 sites in 2017 at wide range of altitudes from 1,359 to 2,645 m. Sipha maydis occurred mainly in NW and SW Colorado and NE New Mexico along with a few sites in NE Colorado, SE Utah, and SE Wyoming. This aphid mainly infested wheat followed by a variety of eight wild grass species. No parasites, predators, sexual morphs, or significant plant damage occurred at the sites. Sipha maydis utilized 14 hosts in the United States including 8 new host records, which expands its host range to 52 plant species worldwide. Sipha maydis may be of concern to wheat, barley, and sorghum production in the United States if its populations continue to increase.

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