scholarly journals The role of pollinators in maintaining variation in flower colour in the Rocky Mountain columbine,Aquilegia coerulea

2015 ◽  
Vol 115 (6) ◽  
pp. 971-979 ◽  
Author(s):  
Margaret W. Thairu ◽  
Johanne Brunet
Keyword(s):  
Flower Colour ◽  
Rocky Mountain

scholarly journals A Landscape Approach to Aspen Restoration: Understanding the Role of Biophysical Setting in Aspen Community Dynamics

2002 ◽  
Vol 26 ◽  
pp. 97-102
Author(s):  
Kathryn Brown ◽  
Andrew Hansen ◽  
Robert Keane ◽  
Lisa Graumlich
Keyword(s):  
Populus Tremuloides ◽  
Community Dynamics ◽  
Rocky Mountain ◽  
Small Sample ◽  
Quaking Aspen ◽  
Climatic Fluctuations ◽  
Conifer Encroachment ◽  
Considerable Debate ◽  
Fire Exclusion

Considerable debate surrounds the persistence of quaking aspen (Populus tremuloides) communities in western North America. Loss of aspen cover has been documented in several studies in various Rocky Mountain ecosystems (Loope and Gruel 1973; Romme et al. 1995; Renkin and Despain 1996; Wirth et al. 1996; Baker et al. 1997; Kay 1997; Bartos and Campbell 1998; White et al. 1998; Gallant et al. 2003). Explanations for loss of aspen include conifer encroachment, fire exclusion, herbivory, and climatic fluctuations (Loope and Gruell 1973; Mueggler 1985; Bartos et al. 1994; Romme et al. 1995; Kay 1997; White et al. 1998). However, many studies documenting aspen decline have been geographically limited or based on a small sample of subjectively chosen stands (Barnett and Stohlgren 2001; Hessl 2002; Kaye et al. 2003).

scholarly journals Nested Recharge Systems in Mountain Block Hydrology: High-Elevation Snowpack Generates Low-Elevation Overwinter Baseflow in a Rocky Mountain River

Water ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2249
Author(s):  
Éowyn M. S. Campbell ◽  
M. Cathryn Ryan
Keyword(s):  
Rocky Mountain ◽  
High Elevation ◽  
Third Order ◽  
Relative Temperature ◽  
Local Flow ◽  
Fracture Systems ◽  
Lower Elevation ◽  
Flow Systems ◽  
Longitudinal Sampling

The majority of each year′s overwinter baseflow (i.e., winter streamflow) in a third-order eastern slopes tributary is generated from annual melting of high-elevation snowpack which is transmitted through carbonate and siliciclastic aquifers. The Little Elbow River and its tributaries drain a bedrock system formed by repeated thrust faults that express as the same siliciclastic and carbonate aquifers in repeating outcrops. Longitudinal sampling over an 18 km reach was conducted at the beginning of the overwinter baseflow season to assess streamflow provenance. Baseflow contributions from each of the two primary aquifer types were apportioned using sulfate, δ34SSO4, and silica concentrations, while δ18OH2O composition was used to evaluate relative temperature and/or elevation of the original precipitation. Baseflow in the upper reaches of the Little Elbow was generated from lower-elevation and/or warmer precipitation primarily stored in siliciclastic units. Counterintuitively, baseflow generated in the lower-elevation reaches originated from higher-elevation and/or colder precipitation stored in carbonate units. These findings illustrate the role of nested flow systems in mountain block recharge: higher-elevation snowmelt infiltrates through fracture systems in the cliff-forming—often higher-elevation—carbonates, moving to the lower-elevation valley through intermediate flow systems, while winter baseflow in local flow systems in the siliciclastic valleys reflects more influence from warmer precipitation. The relatively fast climatic warming of higher elevations may alter snowmelt timing, leaving winter water supply vulnerable to climatic change.

scholarly journals Community Structure and Functional Role of Limber Pine (Pinus flexilis) in Treeline Communities in Rocky Mountain National Park

Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 838
Author(s):  
Laurel A. Sindewald ◽  
Diana F. Tomback ◽  
Eric R. Neumeyer
Keyword(s):  
National Park ◽  
Functional Role ◽  
Rocky Mountain ◽  
Rocky Mountain National Park ◽  
Tree Islands ◽  
Pinus Flexilis ◽  
Tree Island ◽  
Limber Pine ◽  
Study Sites

Research Highlights: Limber pine (Pinus flexilis) is abundant in some alpine treeline ecotone (ATE) communities east of the Continental Divide in Rocky Mountain National Park (RMNP) and the Colorado Front Range. Limber pine may be able to colonize the ATE under changing climate aided by directed seed dispersal by Clark’s nutcrackers (Nucifraga columbiana). Cronartium ribicola, white pine blister rust, is a growing threat to limber pine and may affect its functional role within the ATE. Background and Objectives: The ATE is sensitive, worldwide, to increasing temperature. However, the predicted advance of treeline under a changing climate may be modified by tree species composition and interactions. We aimed to (1) examine the conifer species composition and relative abundances in treeline communities with limber pine; (2) assess which functional roles limber pine assumes in these communities—tree island initiator, tree island component, and/or solitary tree; and (3) determine whether limber pine’s occurrence as a tree island initiator can be predicted by its relative abundance as a solitary tree. Materials and Methods: We selected four study sites in RMNP above subalpine forest limber pine stands. We sampled the nearest tree island to each of forty random points in each study site as well as solitary tree plots. Results: Across study sites, limber pine comprised, on average, 76% of solitary trees and was significantly more abundant as a solitary tree than Engelmann spruce (Picea engelmannii) or subalpine fir (Abies lasiocarpa). Limber pine was a frequent component of multi-tree islands in three study sites, the major component in one study site, and dominated single-tree islands at two study sites. At three of four study sites, no species had significantly greater odds of being a tree island initiator. Limber pine was found less often as a tree island initiator than predicted from its relative abundance as a solitary tree, given the likely role of solitary trees in tree island formation.

scholarly journals Unchanged Survival Rates of 14-3-3γ Knockout Mice after Inoculation with Pathological Prion Protein

2005 ◽  
Vol 25 (4) ◽  
pp. 1339-1346 ◽  
Author(s):  
Petra Steinacker ◽  
Petra Schwarz ◽  
Kerstin Reim ◽  
Peter Brechlin ◽  
Olaf Jahn ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Western Blot ◽  
Neuronal Damage ◽  
Survival Rates ◽  
Rocky Mountain ◽  
Laboratory Strain ◽  
Clinical Findings ◽  
Jakob Disease ◽  
Mutant Mouse Line

ABSTRACT The diagnosis of sporadic Creutzfeldt-Jakob disease (CJD) is based on typical clinical findings and is supported by a positive 14-3-3 Western blot of cerebrospinal fluid. However, it is not clear whether 14-3-3 indicates general neuronal damage or is of pathophysiological relevance in CJD. The fact that the 14-3-3 isoform spectrum in cerebrospinal fluid does not correspond to that found in the brain points to a regulated process. To investigate a possible role of 14-3-3 proteins in transmissible spongiform diseases, we generated a 14-3-3γ-deficient mutant mouse line by using a classical knockout strategy. The anatomy and cage behavior of the mutant mice were normal. Western blot analyses of brain homogenates revealed no changes in the protein expression of other 14-3-3 isoforms (ε, β, ζ, and η). Proteomic analyses of mouse brains by two-dimensional differential gel electrophoresis showed that several proteins, including growth hormone, 1-Cys peroxiredoxin, CCT-zeta, glucose-6-phosphate isomerase, GRP170 precursor, and α-SNAP, were differentially expressed. Mutant and wild-type mice were inoculated either intracerebrally or intraperitoneally with the Rocky Mountain Laboratory strain of scrapie, but no differences were detected in the postinoculation survival rates. These results indicate that 14-3-3γ is unlikely to play a causal role in CJD and related diseases.

scholarly journals Observations of gas- and aerosol-phase organic nitrates at BEACHON-RoMBAS 2011

2013 ◽  
Vol 13 (1) ◽  
pp. 1979-2034 ◽  
Author(s):  
J. L. Fry ◽  
D. C. Draper ◽  
K. J. Zarzana ◽  
P. Campuzano-Jost ◽  
D. A. Day ◽  
...  
Keyword(s):  
Dynamic Range ◽  
Rocky Mountain ◽  
Colorado Front Range ◽  
Temperature Cycle ◽  
Organic Nitrate ◽  
Organic Nitrates ◽  
Front Range ◽  
Aerosol Formation ◽  
Alkyl Nitrates

Abstract. At the Rocky Mountain Biogenic Aerosol Study (BEACHON-RoMBAS) field campaign in the Colorado front range, July–August 2011, measurements of gas- and aerosol-phase organic nitrates enabled a study of the role of NOx (NOx = NO + NO2) in oxidation of forest-emitted VOCs and subsequent aerosol formation. Substantial formation of peroxy- and alkyl-nitrates is observed every morning, with an apparent 2.9% yield of alkyl nitrates from daytime RO2 + NO reactions. Aerosol-phase organic nitrates, however, peak in concentration during the night, with concentrations up to 140 ppt as measured by both optical spectroscopic and mass spectrometric instruments. The diurnal cycle in aerosol fraction of organic nitrates shows an equilibrium-like response to the diurnal temperature cycle, suggesting some reversible absorptive partitioning, but the full dynamic range cannot be reproduced by thermodynamic repartitioning alone. Nighttime aerosol organic nitrate is observed to be positively correlated with [NO2] × [O3] but not with [O3]. These observations support the role of nighttime NO3-initiated oxidation of monoterpenes as a significant source of nighttime aerosol. Nighttime production of organic nitrates exceeds daytime photochemical production at this site, which we postulate to be representative of the Colorado front range forests.

Saving the Dammed

2019 ◽  
Author(s):  
Ellen Wohl
Keyword(s):  
Ecosystem Services ◽  
Northern Hemisphere ◽  
Nitrate Reduction ◽  
National Park ◽  
Flood Control ◽  
Rocky Mountain ◽  
Wetland Loss ◽  
Rocky Mountain National Park ◽  
River Valleys

The ability of beavers to create an abundant habitat for a diverse array of plants and animals has been analyzed time and again. The disappearance of beavers across the northern hemisphere, and what this effects, has yet to be comprehensively studied. Saving the Dammed analyzes the beneficial role of beavers and their dams in the ecosystem of a river, focusing on one beaver meadow in Colorado. In her latest book, Ellen Wohl contextualizes North St. Vrain Creek by discussing the implications of the loss of beavers across much larger areas. Saving the Dammed raises awareness of rivers as ecosystems and the role beavers play in sustaining the ecosystem surrounding rivers by exploring the macrocosm of global river alteration, wetland loss, and the reduction in ecosystem services. The resulting reduction in ecosystem services span things such as flood control, habitat abundance and biodiversity, and nitrate reduction. Allowing readers to follow her as she crawls through seemingly impenetrable spaces with slow and arduous movements, Wohl provides a detailed narrative of beaver meadows. Saving the Dammed takes readers through twelve months at a beaver meadow in Colorado's Rocky Mountain National Park, exploring how beavers change river valleys and how the decline in beaver populations has altered river ecosystems. As Wohl analyzes and discusses the role beavers play in the ecosystem of a river, readers get to follow her through tight, seemingly impenetrable, crawl spaces as she uncovers the benefit of dams.

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