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  Protein Use and Muscle-Fiber Changes in Free-Ranging, Hibernating Black Bears 

  Author(s):Tinker, Daniel B.; Harlow, H. J.; Beck, T. D. I.
  Date:1998-07-01

  Studies of the metabolic and physiological changes that bears undergo during hibernation have, for the most part, supported the paradigm that bears use only fatty tissues as a metabolic substrate during hibernation. This ...
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  Pseudostellaria Sierrae (Caryophyllaceae), a New Species from California 

  Author(s):Rabeler, R. K.; Hartman, Ronald L.
  Date:2002-03-01

  Pseudostellaria sierrae is described a, new from northern California. Glabrous stems and leaves, a V-shaped apical notch in each ligulate petal, five yellow anthers, and seeds with minute projections oil each tubercle are ...
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  Shrub Encroachment Alters Sensitivity of Soil Respiration to Temperature and Moisture 

  Author(s):Cable, J. M.; Barron-Gafford, G. A.; Ogle, K.; Pavao-Zuckerman, M.; Scott, R. L.; Williams, David G.; Huxman, T. E.
  Date:2012-01-11

  A greater abundance of shrubs in semiarid grasslands affects the spatial patterns of soil temperature, moisture, and litter, resulting in fertile islands with potentially enhanced soil metabolic activity. The goal of this ...
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  Daily to Decadal Patterns of Precipitation, Humidity, and Photosynthetic Physiology Recorded in the Spines of the Columnar Cactus, Carnegiea Gigantea 

  Author(s):English, N. B.; Dettman, D. L.; Sandquist, D. R.; Williams, David G.
  Date:2010-05-06

  Isotopic analyses of cactus spines grown serially from the apex of long-lived columnar cactuses may be useful for climatological and ecological studies if time series can be reliably determined from spines. To characterize ...
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  On the Representativeness of Plot Size and Location for Scaling Transpiration from Trees to a Stand 

  Author(s):Mackay, D. S.; Ewers, Brent E.; Loranty, M. M.; Kruger, E. L.
  Date:2010-05-19

  Scaling transpiration from trees to larger areas is a fundamental problem in ecohydrology. For scaling stand transpiration from sap flux sensors we asked if plot representativeness depended on plot size and location, the ...
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  Competition for Light Between Individual Trees Lowers Reference Canopy Stomatal Conductance : Results from a Model 

  Author(s):Loranty, M. M.; Mackay, D. S.; Ewers, Brent E.; Traver, E.; Kruger, E. L.
  Date:2010-11-09

  We have used an ecosystem model, TREES (Terrestrial Regional Ecosystem Exchange Simulator), to test the hypothesis that competition for light limits reference canopy stomatal conductance (GSref; conductance at 1 kPa vapor ...
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  Risk-Return Analysis of Incorporating Annual Legumes and Lamb Grazing with Dryland Crop Rotations 

  Author(s):Held, L. J.; Haag, A. A.; Krall, J. M.; Delaney, R. H.; Miller, Steven L.
  Date:2002-01-01

  Profitability and risk, 1988-2001, are examined for lamb-grazed field pea as a fallow alternative with wheat, or an extended wheat-sunflower-millet rotation. Switching from conventional wheat-fallow to an extended rotation ...
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  Sap Flux-Upscaled Canopy Transpiration, Stomatal Conductance, and Water Use Efficiency in an Old Growth Forest in the Great Lakes Region of the United States 

  Author(s):Tang, J. W.; Bolstad, P. V.; Ewers, Brent E.; Desai, A. R.; Davis, K. J.; Carey, E. V.
  Date:2006-06-01

  Combining sap flux and eddy covariance measurements provides a means to study plant stomatal conductance and the relationship between transpiration and photosynthesis. We measured sap flux using Granier-type sensors in a ...
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  Sex-Specific Trade-Offs and Responses to Foliar Shade in the Gynodioecious Species Silene Vulgaris (Caryophyllaceae) 

  Author(s):Dykstra, A. B.; Brock, M. T.; Delph, L. F.; Weinig, Cynthia
  Date:2009-06-01

  Allocation trade-offs are predicted to affect evolutionary dynamics, including the evolution of sexual dimorphism. In gynodioecious species, where populations have both females and hermaphrodites, selection may result in ...
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  Controls on Soil Organic Carbon and Nitrogen in Inner Mongolia, China : A Cross-Continental Comparison of Temperate Grasslands 

  Author(s):Evans, S. E.; Burke, Ingrid; Lauenroth, William K.
  Date:2011-07-12

  Most global ecosystem models assume that controls over soil organic matter are alike in climatically similar regions. In this study, we tested the generality of controls over soil organic carbon (SOC) and soil organic ...
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  Elevated Atmospheric Co2 Effects and Soil Water Feedbacks on Soil Respiration Components in a Colorado Grassland 

  Author(s):Pendall, Elise; Del Grosso, S.; King, J. Y.; LeCain, D. R.; Milchunas, D. G.; Morgan, J. A.; Mosier, A. R.; Ojima, D. S.; Parton, W. A.; Tans, P. P.; White, J. W. C.
  Date:2003-05-15

  The shortgrass steppe is a semi-arid grassland, where elevated CO2 reduces stomatal conductance and promotes soil moisture storage. Enhanced biomass growth from elevated CO2 has been attributed in part to soil moisture ...
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  Rapid Hydrologic Shifts and Prolonged Droughts in Rocky Mountain Headwaters During the Holocene 

  Author(s):Shuman, B.; Pribyl, P.; Minckley, Thomas; Shinker, J. J.
  Date:2010-03-16

  Rapid hydroclimatic shifts repeatedly generated centuries to millennia of extensive aridity across the headwaters of three of North America's largest river systems during the Holocene. Evidence of past lake-level changes ...
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  Patterns and Sources of Multidecadal Oscillations in Drought-Sensitive Tree-Ring Records from the Central and Southern Rocky Mountains 

  Author(s):Gray, S. T.; Betancourt, J. L.; Fastie, C. L.; Jackson, Stephen T.
  Date:2003-03-26

  Tree-ring records spanning the past seven centuries from the central and southern Rocky Mountains were studied using wavelet analysis to examine multidecadal (>30-70 yr) patterns of drought variation. Fifteen tree-ring ...
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  Differential Hydrogen Isotopic Ratios of Sphagnum and Vascular Plant Biomarkers in Ombrotrophic Peatlands as a Quantitative Proxy for Precipitation-Evaporation Balance 

  Author(s):Nichols, J.; Booth, R. K.; Jackson, Stephen T.; Pendall, Elise; Huang, Y. S.
  Date:2010-02-15

  We have developed a new approach to quantitatively reconstruct past changes in evaporation based on compound-specific hydrogen isotope ratios of vascular plant and Sphagnum biomarkers in ombrotrophic peatland sediments. ...
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  Morphological Variation of Some Floral Features of the Subfamily Pitcairnioideae (Bromeliaceae) and Their Significance in Pollination Biology 

  Author(s):Varadarajan, G. S.; Brown, Gregory K.
  Date:1988-03-01

  Scanning electron and light microscopy observations of wet-preserved flowers of Bromeliaceae subfamily Pitcaimioideae yield new information on the stigma, petal scales, and septal nectaries. Variations of the stigma types ...
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  Carbon and Oxygen Isotope Analysis of Leaf Biomass Reveals Contrasting Photosynthetic Responses to Elevated Co2 Near Geologic Vents in Yellowstone National Park 

  Author(s):Sharma, S.; Williams, David G.
  Date:2009-01-01

  In this study we explore the use of natural CO2 emissions in Yellowstone National Park (YNP) in Wyoming, USA to study responses of natural vegetation to elevated CO2 levels. Radiocarbon (14C) analysis of leaf biomass from ...
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  Cladistic Relationships of Aechmea (Bromeliaceae, Bromelioideae) and Allied Genera 

  Author(s):de Faria, A. P. G.; Wendt, T.; Brown, Gregory K.
  Date:2004-01-01

  Aechmea (ca. 220 species) is the largest and most diverse genus in Bromelioideae (Bromeliaceae), and several dissimilar generic concepts and infrageneric classifications have been proposed, frequently involving other closely ...
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  Phylogeny, Adaptive Radiation, and Historical Biogeography in Bromeliaceae : Insights from an Eight-Locus Plastid Phylogeny 

  Author(s):Givnish, T. J.; Barfuss, M. H. J.; Van Ee, B.; Riina, R.; Schulte, K.; Horres, R.; Gonsiska, P. A.; Jabaily, R. S.; Crayn, D. M.; Smith, J. A. C.; Winter, K.; Brown, Gregory K.; Evans, T. M.; Holst, B. K.; Luther, H.; Till, W.; Zizka, G.; Berry, P. E.; Sytsma, K. J.
  Date:2011-05-01

  Premise: Bromeliaceae form a large, ecologically diverse family of angiosperms native to the New World. We use a bromeliad phylogeny based on eight plastid regions to analyze relationships within the family, test a new, ...
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  Reclassification of North American Haplopappus (Compositae : Astereae) Completed : Rayjacksonia Gen Nov 

  Author(s):Lane, M. A.; Hartman, Ronald L.
  Date:1996-03-01

  Rayjacksonia R. L. Hartman & M. A. Lane, gen. nov. (Compositae: Astereae), is named to accommodate the ''phyllocephalus complex,'' formerly of Haplopappus Cass. sect. Blepharodon DC. The new combinations are R. phyllocephalus ...
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  Examination of Subfamilial Phylogeny in Bromeliaceae Using Comparative Sequencing of the Plastid Locus Ndhf 

  Author(s):Terry, R. G.; Brown, Gregory K.; Olmstead, R. G.
  Date:1997-05-01

  Parsimony analysis of 31 sequences of the chloroplast locus ndhF was used to address questions of subfamilial phylogeny in Bromeliaceae. Results presented here are congruent with those from chloroplast DNA restriction site ...

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