Search Results - "Ryel, Ronald J."

Rapid modulation of ultraviolet shielding in plants is influenced by solar ultraviolet radiation and linked to alterations in flavonoids by Barnes, Paul W, Tobler, Mark A, Keefover‐Ring, Ken, Flint, Stephan D, Barkley, Anne E, Ryel, Ronald J, Lindroth, Richard L

“…The accumulation of ultraviolet (UV)‐absorbing compounds (flavonoids and related phenylpropanoids) and the resultant decrease in epidermal UV transmittance…”
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UV Screening in Native and Non-native Plant Species in the Tropical Alpine: Implications for Climate Change-Driven Migration of Species to Higher Elevations by Barnes, Paul W, Ryel, Ronald J, Flint, Stephan D

“…Ongoing changes in Earth's climate are shifting the elevation ranges of many plant species with non-native species often experiencing greater expansion into…”
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Continental-scale assessment of genetic diversity and population structure in quaking aspen (Populus tremuloides) by Callahan, Colin M., Rowe, Carol A., Ryel, Ronald J., Shaw, John D., Madritch, Michael D., Mock, Karen E.

“…Aim Quaking aspen (Populus tremuloides) has the largest natural distribution of any tree native to North America. The primary objectives of this study were to…”
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Widespread Triploidy in Western North American Aspen (Populus tremuloides) by Mock, Karen E, Callahan, Colin M, Islam-Faridi, M. Nurul, Shaw, John D, Rai, Hardeep S, Sanderson, Stewart C, Rowe, Carol A, Ryel, Ronald J, Madritch, Michael D, Gardner, Richard S, Wolf, Paul G, Niedz, Randall P

“…We document high rates of triploidy in aspen (Populus tremuloides) across the western USA (up to 69% of genets), and ask whether the incidence of triploidy…”
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Aspen succession and nitrogen loading: a case for epiphytic lichens as bioindicators in the Rocky Mountains, USA by Rogers, Paul C., Moore, Kori D., Ryel, Ronald J.

“…Question: Can lichen communities be used to assess shortand long-term factors affecting seral quaking aspen (Populus tremuloides) communities at the landscape…”
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Avian Response to Frost-Damaged Aspen in Northern Utah by Leidolf, Andreas, Ryel, Ronald J.

“…In early May 2007, northern Utah mountains experienced a period of prolonged warmer-than-normal temperatures, followed by a frost that killed or damaged much…”
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Diurnal adjustment in ultraviolet sunscreen protection is widespread among higher plants by Barnes, Paul W, Flint, Stephan D, Tobler, Mark A, Ryel, Ronald J

“…The accumulation of ultraviolet (UV)-absorbing compounds (flavonoids and related phenylpropanoids) in the epidermis of higher plants reduces the penetration of…”
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Internal hydraulic redistribution prevents the loss of root conductivity during drought by Prieto, Iván, Ryel, Ronald J

“…Shrubs of the Great Basin desert in Utah are subjected to a prolonged summer drought with the potential consequence of reduced water transport capability of…”
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Rediscovering leaf optical properties: New insights into plant acclimation to solar UV radiation by Barnes, Paul W., Flint, Stephan D., Ryel, Ronald J., Tobler, Mark A., Barkley, Anne E., Wargent, Jason J.

“…The accumulation of UV-absorbing compounds (flavonoids and other phenylpropanoid derivatives) and resultant decrease in the UV transmittance of the epidermis…”
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Soil Water Repellency: A Method of Soil Moisture Sequestration in Pinyon–Juniper Woodland by Robinson, David A, Lebron, Inma, Ryel, Ronald J, Jones, Scott B

“…Encroachment of pinyon–juniper woodland into rangeland ecosystems is prevalent across the western United States. Mechanisms associated with this successful…”
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Landscape assessment of a stable aspen community in southern Utah, USA by Rogers, Paul C., Leffler, A. Joshua, Ryel, Ronald J.

“…Recent reports of rapid die-off of aspen (Populus tremuloides), coupled with vigorous debate over long-term reduction of aspen cover in western North America,…”
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Adjustments in epidermal UV-transmittance of leaves in sun-shade transitions by Barnes, Paul W., Kersting, Anna R., Flint, Stephan D., Beyschlag, Wolfram, Ryel, Ronald J.

“…Epidermal UV transmittance (TUV) and UV‐absorbing compounds were measured in sun and shade leaves of Populus tremuloides and Vicia faba exposed to contrasting…”
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Gas exchange and growth responses of the desert shrubs Artemisia tridentata and Chrysothamnus nauseosus to shallow- vs. deep-soil water in a glasshouse experiment by Leffler, A.Joshua, Ivans, Carolyn Y., Ryel, Ronald J., Caldwell, Martyn M.

“…The aridland shrub species, Artemisia tridentata (big sagebrush) and Chrysothamnus nauseosus (rubber rabbitbrush), are distributed widely in the Intermountain…”
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A Functional Framework for Improved Management of Western North American Aspen (Populus tremuloides Michx.) by Rogers, Paul C., Landhäusser, Simon M., Pinno, Bradley D., Ryel, Ronald J.

“…Quaking or trembling aspen (Populus tremuloides Michx.) forests occur in highly diverse settings across North America. However, management of distinct…”
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How Much Variance Is Explained by Ecologists? Additional Perspectives by Peek, Michael S., Leffler, A. Joshua, Flint, Stephan D., Ryel, Ronald J.

“…A recent meta-analysis of meta-analyses by Møller and Jennions (2002, Oecologia 132: 492-500) suggested that ecologists using statistical models are explaining…”
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Influence of Sampling Frequency on Estimation of Annual Total Phosphorus and Total Suspended Solids Loads by Jones, Amber Spackman, Horsburgh, Jeffery S., Mesner, Nancy O., Ryel, Ronald J., Stevens, David K.

“…The determination of sediment and nutrient loads is typically based on the collection and analysis of grab samples. The frequency and regularity of traditional…”
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Lichen community change in response to succession in aspen forests of the southern Rocky Mountains by Rogers, Paul C., Ryel, Ronald J.

“…In western North America, quaking aspen ( Populus tremuloides) is the most common hardwood in montane landscapes. Fire suppression, grazing and wildlife…”
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Exploring succession within aspen communities using a habitat-based modeling approach by Mittanck, Cody M., Rogers, Paul C., Ramsey, R. Douglas, Bartos, Dale L., Ryel, Ronald J.

“…•We modeled aspen and conifer distributions using a generalized linear model.•We analyzed results in terms of stable and seral habitat for aspen…”
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Diurnal changes in epidermal UV transmittance of plants in naturally high UV environments by Barnes, Paul W, Flint, Stephan D, Slusser, James R, Gao, Wei, Ryel, Ronald J

“…Studies were conducted on three herbaceous plant species growing in naturally high solar UV environments in the subalpine of Mauna Kea, Hawaii, USA, to…”
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Testing soil phytolith analysis as a tool to understand vegetation change in the sagebrush steppe and pinyon-juniper woodlands of the Great Basin Desert, USA by Morris, Lesley R., West, Neil E., Ryel, Ronald J.

“…Better biological proxy methods are needed to understand changes in arid ecosystems over the recent past. Our objective in this study was to examine the…”
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