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Full-Text Articles in Life Sciences

Grass-Shrub Associations Over A Precipitation Gradient And Their Implications For Restoration In The Great Basin, Usa, Maike F. Holthuijzen, Kari E. Veblen Dec 2015

Grass-Shrub Associations Over A Precipitation Gradient And Their Implications For Restoration In The Great Basin, Usa, Maike F. Holthuijzen, Kari E. Veblen

Wildland Resources Faculty Publications

As environmental stress increases positive (facilitative) plant interactions often predominate. Plant-plant associations (or lack thereof) can indicate whether certain plant species favor particular types of microsites (e.g., shrub canopies or plant-free interspaces) and can provide valuable insights into whether “nurse plants” will contribute to seeding or planting success during ecological restoration. It can be difficult, however, to anticipate how relationships between nurse plants and plants used for restoration may change over large-ranging, regional stress gradients. We investigated associations between the shrub, Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis), and three common native grasses (Poa secunda, Elymus elymoides, and Pseudoroegneria spicata), …


Evaluating Vital Rate Contributions To Greater Sage-Grouse Population Dynamics To Inform Conservation, David K. Dahlgren Nov 2015

Evaluating Vital Rate Contributions To Greater Sage-Grouse Population Dynamics To Inform Conservation, David K. Dahlgren

Wildland Resources Faculty Publications

Species conservation efforts often use short-term studies that fail to identify the vital rates that contribute most to population growth. Although the greater sage-grouse (Centrocercus urophasianus; sage-grouse) is a candidate for protection under the U.S. Endangered Species Act, and is sometimes referred to as an umbrella species in the sagebrush (Artemisia spp.) biome of western North America, the failure of proposed management strategies to focus on key vital rates that may contribute most to achieving population stability remains problematic for sustainable conservation. To address this dilemma, we performed both prospective and retrospective perturbation analyses of a life cycle model based …


Thermal Patterns Constrain Diurnal Behavior Of A Ground-Dwelling Bird, J. Matthew Carroll, Craig A. Davis, R. Dwayne Elmore, Samuel D. Fuhlendorf, Eric T. Thacker Nov 2015

Thermal Patterns Constrain Diurnal Behavior Of A Ground-Dwelling Bird, J. Matthew Carroll, Craig A. Davis, R. Dwayne Elmore, Samuel D. Fuhlendorf, Eric T. Thacker

Wildland Resources Faculty Publications

Recently, gaining knowledge about thermal refuges for vulnerable species has been a major focal point of ecological studies, and this focus has been heightened by predicted temperature increases associated with global climate change. To better understand how organisms respond to thermal landscapes and extremes, we investigated the thermal ecology of a gallinaceous bird species (northern bobwhite; Colinus virginianus, hereafter bobwhite) during a key life history period. Specifically, our study focused on the brood-rearing period of precocial bobwhite chicks associated with brood-attending adults. We measured site-specific black bulb temperatures (Tbb) and vegetation characteristics across 38 brood tracking days and 68 random …


Beneficial Effects Of Temperate Forage Legumes That Contain Condensed Tannins, Jennifer W. Macadam, Juan J. Villalba Jul 2015

Beneficial Effects Of Temperate Forage Legumes That Contain Condensed Tannins, Jennifer W. Macadam, Juan J. Villalba

Wildland Resources Faculty Publications

The two temperate forage legumes containing condensed tannins (CT) that promote ruminant production are birdsfoot trefoil (Lotus corniculatus L.; BFT) and sainfoin (Onobrychis viciifolia Scop.; SF). Both are well-adapted to the cool-temperate climate and alkaline soils of the Mountain West USA. Condensed tannins comprise a diverse family of bioactive chemicals with multiple beneficial functions for ruminants, including suppression of internal parasites and enteric methane. Birdsfoot trefoil contains 10 to 40 g·CT·kg−1 dry matter (DM), while SF contains 30 to 80 g·CT·kg−1 DM. Our studies have focused on these two plant species and have demonstrated consistently elevated rates of gain for …


Long-Term Plant Responses To Climate Are Moderated By Biophysical Attributes In A North American Desert, S M. Munson, R H. Webb, D C. Housman, Kari E. Veblen, K E. Nussear, E A. Beever, K B. Hartney, M N. Miriti, S L. Phillips, R E. Fulton, N G. Tallent Apr 2015

Long-Term Plant Responses To Climate Are Moderated By Biophysical Attributes In A North American Desert, S M. Munson, R H. Webb, D C. Housman, Kari E. Veblen, K E. Nussear, E A. Beever, K B. Hartney, M N. Miriti, S L. Phillips, R E. Fulton, N G. Tallent

Wildland Resources Faculty Publications

Recent elevated temperatures and prolonged droughts in many already water-limited regions throughout the world, including the southwestern United States, are likely to intensify according to future climate-model projections. This warming and drying can negatively affect perennial vegetation and lead to the degradation of ecosystem properties. To better understand these detrimental effects, we formulate a conceptual model of dryland ecosystem vulnerability to climate change that integrates hypotheses on how plant species will respond to increases in temperature and drought, including how plant responses to climate are modified by landscape, soil and plant attributes that are integral to water availability and use. …


How Does Variation In Winter Weather Affect Deer-Vehicle Collision Rates, Daniel D. Olson, John A. Bissonette, Patricia C. Cramer, Patrick J. Jackson, Kevin D. Bunnell, Daniel C. Coster Mar 2015

How Does Variation In Winter Weather Affect Deer-Vehicle Collision Rates, Daniel D. Olson, John A. Bissonette, Patricia C. Cramer, Patrick J. Jackson, Kevin D. Bunnell, Daniel C. Coster

Wildland Resources Faculty Publications

Understanding how deer move in relationship to roads is critical, because deer are in vehicle collisions, and collisions cause vehicle damage, as well as human injuries and fatalities. In temperate climates, mule deer Odocoileus hemionus have distinct movement patterns that affect their spatial distribution in relationship to roads. In this paper, we analyzed deer movements during two consecutive winter seasons with vastly different conditions to determine how deer—vehicle collision rates responded. We predicted that deer—vehicle collision rates would be higher when precipitation and snow depth were higher. We used meteorological data from local weather stations to describe temperature, precipitation and …


Predation Threat Alters Composition And Functioning Of Bromeliad Ecosystems, Edd Hammill, Trisha B. Atwood, Diane S. Srivastava Mar 2015

Predation Threat Alters Composition And Functioning Of Bromeliad Ecosystems, Edd Hammill, Trisha B. Atwood, Diane S. Srivastava

Wildland Resources Faculty Publications

Predators can have dramatic effects on food web structure and ecosystem processes. However, the total effect of predators will be a combination of prey removal due to consumption and non-consumptive effects (NCEs) mediated through changes to prey behavioral, morphological, or life history traits induced to reduce predation risk. In this study, we examined how consumptive and NCEs alter community composition and ecosystem function using the aquatic ecosystem housed within tropical bromeliads. We allowed the recolonization of emptied bromeliads containing either no predators, caged predators (NCEs only), or uncaged predators (NCEs and consumptive effects) and recorded densities of all macro-invertebrates, microbial …


Transition From Sagebrush Steppe To Annual Grass (Bromus Tectorum): Influence On Belowground Carbon And Nitrogen, Benjamin M. Rau, Dale W. Johnson, Robert R. Blank, Annmarrie Lucchesi, Todd G. Caldwell, Eugene W. Schupp Feb 2015

Transition From Sagebrush Steppe To Annual Grass (Bromus Tectorum): Influence On Belowground Carbon And Nitrogen, Benjamin M. Rau, Dale W. Johnson, Robert R. Blank, Annmarrie Lucchesi, Todd G. Caldwell, Eugene W. Schupp

Wildland Resources Faculty Publications

Vegetation changes associated with climate shifts and anthropogenic disturbance have major impacts on biogeochemical cycling. Much of the interior western United States currently is dominated by sagebrush (Artemisia tridentata Nutt.) ecosystems. At low to intermediate elevations, sagebrush ecosystems increasingly are influenced by cheatgrass (Bromus tectorum L.) invasion. Little currently is known about the distribution of belowground organic carbon (OC) on these changing landscapes, how annual grass invasion affects OC pools, or the role that nitrogen (N) plays in carbon (C) retention. As part of a Joint Fire Sciences-funded project called the Sagebrush Treatment Evaluation Project (SageSTEP), we quantified …


Naturalization Of Almond Trees (Prunus Dulcis) In Semi-Arid Regions Of The Western Mediterranean., Pablo Homet-Gutierrez, Eugene W. Schupp, José M. Gómez Feb 2015

Naturalization Of Almond Trees (Prunus Dulcis) In Semi-Arid Regions Of The Western Mediterranean., Pablo Homet-Gutierrez, Eugene W. Schupp, José M. Gómez

Wildland Resources Faculty Publications

Agricultural land abandonment is rampant in present day Europe. A major consequence of this phenomenon is the re-colonization of these areas by the original vegetation. However, some agricultural, exotic species are able to naturalize and colonize these abandoned lands. In this study we explore the ability of almonds (Prunus dulcis D.A. Webb.) to establish in abandoned croplands in semi-arid areas of SE Iberian Peninsula. Domesticated during the early Holocene in SW Asia and the Eastern Mediterranean, the almond has spread as a crop all over the world. We established three plots adjacent to almond orchards on land that was abandoned …


Lichen Monitoring Delineates Biodiversity On A Great Barrier Reef Coral Cay, Paul C. Rogers, Roderick W. Rogers, Anne Hedrich, Patrick T. Moss Jan 2015

Lichen Monitoring Delineates Biodiversity On A Great Barrier Reef Coral Cay, Paul C. Rogers, Roderick W. Rogers, Anne Hedrich, Patrick T. Moss

Wildland Resources Faculty Publications

Coral islands around the world are threatened by changing climates. Rising seas, drought, and increased tropical storms are already impacting island ecosystems. We aim to better understand lichen community ecology of coral island forests. We used an epiphytic lichen community survey to gauge Pisonia (Pisonia grandis R.BR.), which dominates forest conditions on Heron Island, Australia. Nine survey plots were sampled for lichen species presence and abundance, all tree diameters and species, GPS location, distance to forest-beach edge, and dominant forest type. Results found only six unique lichens and two lichen associates. A Multi-Response Permutation Procedures (MRPP) test found statistically distinct …


If Long-Term Resistance To A Spruce Beetle Epidemic Is Futile, Can Silvicultural Treatments Increase Resilience In Spruce-Fir Forests In The Central Rocky Mountains?, Marcella A. Windmuller-Campione, James N. Long Jan 2015

If Long-Term Resistance To A Spruce Beetle Epidemic Is Futile, Can Silvicultural Treatments Increase Resilience In Spruce-Fir Forests In The Central Rocky Mountains?, Marcella A. Windmuller-Campione, James N. Long

Wildland Resources Faculty Publications

Within the Central Rocky Mountains, spruce beetle populations have the potential to rapidly transition from endemic to epidemic levels in the spruce-fir (Engelmann spruce and subalpine fir) forest type. Conventional management has focused on creating resistance to spruce beetle outbreaks by manipulating the overstory density and composition. Three silvicultural treatments, single tree selection, group selection, and shelterwood with reserves, were established in a spruce-fir forest in northern Utah with the goals of increasing both resistance and resilience to outbreaks. Resistance and resilience metrics were explicitly defined. Pre-harvest and two post-harvest measurements were used to assess how the different silvicultural treatments …


Environmental Drivers Of Deadwood Dynamics In Woodlands And Forests, M. Garbarino, R. Marzano, J. D. Shaw, James N. Long Jan 2015

Environmental Drivers Of Deadwood Dynamics In Woodlands And Forests, M. Garbarino, R. Marzano, J. D. Shaw, James N. Long

Wildland Resources Faculty Publications

Deadwood dynamics play a key role in many forest ecosystems. Understanding the mechanisms involved in the accumulation and depletion of deadwood can enhance our understanding of fundamental processes such as carbon sequestration and disturbance regimes, allowing better predictions of future changes related to alternative management and climate scenarios. A conceptual framework for deadwood dynamics has been generally accepted but has not been broadly tested with empirical data. We used a large (n ¼ 6191) data set containing measurements of live and standing dead trees, and downed woody material, representing numerous woodland and forest types from throughout the Interior Western USA, …


Comparative Evolutionary Diversity And Phylogenetic Structure Across Multiple Forest Dynamics Plots: A Mega-Phylogeny Approach, D. L. Erickson, F. A. Jones, N. G. Swenson, N. Pei, N. Bourg, W. Chen, S. J. Davies, X. Ge, Z. Hao, R. W. Howe, C. L. Huang, A. Larson, S. Lum, James A. Lutz, K. Ma, M. Meegaskumbura, X. Mi, J. D. Parker Jan 2015

Comparative Evolutionary Diversity And Phylogenetic Structure Across Multiple Forest Dynamics Plots: A Mega-Phylogeny Approach, D. L. Erickson, F. A. Jones, N. G. Swenson, N. Pei, N. Bourg, W. Chen, S. J. Davies, X. Ge, Z. Hao, R. W. Howe, C. L. Huang, A. Larson, S. Lum, James A. Lutz, K. Ma, M. Meegaskumbura, X. Mi, J. D. Parker

Wildland Resources Faculty Publications

Forest dynamics plots, which now span longitudes, latitudes, and habitat types across the globe, offer unparalleled insights into the ecological and evolutionary processes that determine how species are assembled into communities. Understanding phylogenetic relationships among species in a community has become an important component of assessing assembly processes. However, the application of evolutionary information to questions in community ecology has been limited in large part by the lack of accurate estimates of phylogenetic relationships among individual species found within communities, and is particularly limiting in comparisons between communities. Therefore, streamlining and maximizing the information content of these community phylogenies is …