Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 11 of 11

Full-Text Articles in Life Sciences

Group Effects Of A Non-Native Plant Invasion On Rodent Abundance, Bryan M. Kluever, Trinity N. Smith, Eric M. Gese Jan 2019

Group Effects Of A Non-Native Plant Invasion On Rodent Abundance, Bryan M. Kluever, Trinity N. Smith, Eric M. Gese

Wildland Resources Faculty Publications

Cheatgrass (Bromus tectorum) is the most prolific invading plant in western North America. Investigations determining the impact of this invasion on population state variables and community dynamics of rodents have largely occurred at the community or species level, creating a knowledge gap as to whether rodents affiliated by a shared taxonomy or other grouping are differentially affected by cheatgrass invasion. We examined rodent abundance along a gradient of cheatgrass cover using various groupings of two nocturnal rodent taxa comprising the majority of the rodent community in the Great Basin Desert. In the summers of 2010–2013, rodents were sampled and ...


Short-Term Regeneration Dynamics Of Wyoming Big Sagebrush At Two Sites In Northern Utah, Sara J. Germain, Rebecca K. Mann, Thomas A. Monaco, Kari E. Veblen Apr 2018

Short-Term Regeneration Dynamics Of Wyoming Big Sagebrush At Two Sites In Northern Utah, Sara J. Germain, Rebecca K. Mann, Thomas A. Monaco, Kari E. Veblen

Wildland Resources Faculty Publications

Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) is a widespread shrub across the western United States, and there is great interest among scientists and land managers in its ecology and conservation, particularly with regard to maintaining structural heterogeneity of sagebrush stands for wildlife habitat and livestock forage. Yet little is known about its short-term regeneration dynamics and the implications of those dynamics for changes in stand structure. We examined changes among sagebrush size classes across 3 years, as well as emergence of sagebrush from seed bank and seed rain samples at 2 sagebrush shrub land sites in northern Utah: a ...


Herbivory And Drought Generate Short‐Term Stochasticity And Long‐Term Stability In A Savanna Understory Community, Corinna Riginos, Lauren M. Porensky, Kari E. Veblen, Truman P. Young Mar 2018

Herbivory And Drought Generate Short‐Term Stochasticity And Long‐Term Stability In A Savanna Understory Community, Corinna Riginos, Lauren M. Porensky, Kari E. Veblen, Truman P. Young

Wildland Resources Faculty Publications

Rainfall and herbivory are fundamental drivers of grassland plant dynamics, yet few studies have examined long‐term interactions between these factors in an experimental setting. Understanding such interactions is important, as rainfall is becoming increasingly erratic and native wild herbivores are being replaced by livestock. Livestock grazing and episodic low rainfall are thought to interact, leading to greater community change than either factor alone. We examined patterns of change and stability in herbaceous community composition through four dry periods, or droughts, over 15 years of the Kenya Long‐term Exclosure Experiment (KLEE), which consists of six different combinations of cattle ...


Is Doping Of Cognitive Performance An Anti‐Herbivore Adaptation? Alkaloids Inhibiting Acetylcholinesterase As A Case, Maciej J. Ejsmond, Fred D. Provenza Feb 2018

Is Doping Of Cognitive Performance An Anti‐Herbivore Adaptation? Alkaloids Inhibiting Acetylcholinesterase As A Case, Maciej J. Ejsmond, Fred D. Provenza

Wildland Resources Faculty Publications

Historically, people who study interactions between plants and herbivores focused on the ecological costs and benefits of synthesizing secondary metabolites. These compounds have diverse functions including defenses against herbivores. Some plants produce alkaloids that act as acetylcholinesterase inhibitors, increasing both the level and duration of action of the neurotransmitter acetylcholine with potential toxic effects in insects and mammals. Yet, among a number of neuroactive plant chemicals, alkaloids that inhibit acetylcholinesterase (AIA) display nootropic activities, that is, positively affect cognition, learning, and memory in mammals. This creates a paradox: Neuroactive AIA, expected to punish herbivores, enhance cognition, learning, and memory. A ...


Plant Identity And Shallow Soil Moisture Are Primary Drivers Of Stomatal Conductance In The Savannas Of Kruger National Park, Rebecca L. Tobin, Andrew Kulmatiski Jan 2018

Plant Identity And Shallow Soil Moisture Are Primary Drivers Of Stomatal Conductance In The Savannas Of Kruger National Park, Rebecca L. Tobin, Andrew Kulmatiski

Wildland Resources Faculty Publications

Our goal was to describe stomatal conductance (gs) and the site-scale environmental parameters that best predict gs in Kruger National Park (KNP), South Africa. Dominant grass and woody species were measured over two growing seasons in each of four study sites that represented the natural factorial combination of mean annual precipitation [wet (750 mm) or dry (450 mm)] and soil type (clay or sand) found in KNP. A machine-learning (random forest) model was used to describe gs as a function of plant type (species or functional group) and site-level environmental parameters (CO2, season, shortwave radiation, soil type, soil moisture, time ...


Road Dust Correlated With Decreased Reproduction Of The Endangered Utah Shrub Hesperidanthus Suffrutescens, Matthew B. Lewis, Eugene W. Schupp, Thomas A. Monaco Dec 2017

Road Dust Correlated With Decreased Reproduction Of The Endangered Utah Shrub Hesperidanthus Suffrutescens, Matthew B. Lewis, Eugene W. Schupp, Thomas A. Monaco

Wildland Resources Faculty Publications

Roads associated with energy development have fragmented much of the Uinta Basin, the Colorado Plateau in general, and other areas of western North America. Beyond reducing available habitat, spreading exotic species, and creating barriers to dispersal, unpaved roads also increase dust loads on plants and pollinators, which may reduce plant growth and reproduction. We studied the effects of an unpaved road on reproduction of an endangered Utah endemic shrub. We measured the size and reproductive output of 156 plants and the dust deposition in plots at increasing distances from the road. We also hand outcrossed 240 flowers from 80 plants ...


Forecasting Climate Change Impacts On Plant Populations Over Large Spatial Extents, Andrew T. Tredennick, Mevi B. Hooten, Cameron L. Aldridge, Collin G. Homer, Andrew R. Kleinhesselink, Peter Adler Oct 2016

Forecasting Climate Change Impacts On Plant Populations Over Large Spatial Extents, Andrew T. Tredennick, Mevi B. Hooten, Cameron L. Aldridge, Collin G. Homer, Andrew R. Kleinhesselink, Peter Adler

Wildland Resources Faculty Publications

Plant population models are powerful tools for predicting climate change impacts in one location, but are difficult to apply at landscape scales. We overcome this limitation by taking advantage of two recent advances: remotely sensed, species-specific estimates of plant cover and statistical models developed for spatiotemporal dynamics of animal populations. Using computationally efficient model reparameterizations, we fit a spatiotemporal population model to a 28-year time series of sagebrush (Artemisia spp.) percent cover over a 2.5 × 5 km landscape in southwestern Wyoming while formally accounting for spatial autocorrelation. We include interannual variation in precipitation and temperature as covariates in the ...


Most Soil Trophic Guilds Increase Plant Growth: A Meta-Analytical Review, Andrew Kulmatiski, Andrew Anderson-Smith, Karen H. Beard, Stephen Doucette-Riise, Michael Mazzacavallo, Nicole E. Nolan, Ricardo A. Ramirez, John R. Stevens Jul 2014

Most Soil Trophic Guilds Increase Plant Growth: A Meta-Analytical Review, Andrew Kulmatiski, Andrew Anderson-Smith, Karen H. Beard, Stephen Doucette-Riise, Michael Mazzacavallo, Nicole E. Nolan, Ricardo A. Ramirez, John R. Stevens

Wildland Resources Faculty Publications

Trophic cascades are important drivers of plant and animal abundances in aquatic and aboveground systems, but in soils trophic cascades have been thought to be of limited importance due to omnivory and other factors. Here we use a meta-analysis of 215 studies with 1526 experiments that measured plant growth responses to additions or removals of soil organisms to test how different soil trophic levels affect plant growth. Consistent with the trophic cascade hypothesis, we found that herbivores and plant pathogens (henceforth pests) decreased plant growth and that predators of pests increased plant growth. The magnitude of this trophic cascade was ...


A Functional Framework For Improved Management Of Western North American Aspen (Populus Tremuloides Michx.), Paul C. Rogers, Simon M. Landhausser, Bradley D. Pinno, Ronald J. Ryel Apr 2014

A Functional Framework For Improved Management Of Western North American Aspen (Populus Tremuloides Michx.), Paul C. Rogers, Simon M. Landhausser, Bradley D. Pinno, Ronald J. Ryel

Wildland Resources Faculty Publications

Quaking or trembling aspen (Populus tremuloides Michx.) forests occur in highly diverse setting across North America. However, management of distinct communities has long relied on a single aspen to-conifer successional model. We examine a variety of aspen dominated stand types in the western portion of its range as ecological systems; avoiding an exclusive focus on seral dynamics or single species management. We build a case for a large-scale functional aspen typology based on existing literature. Aspen functional types are defined as aspen communities that differ markedly in their physical and biological processes. The framework presented here describes two “functional types ...


Quantitative-Genetic Variation In Morphological And Physiological Traits Within A Quaking Aspen (Populus Tremuloides) Population, Megan K. Kanaga, Ronald J. Ryel, Karen E. Mock, Michael E. Pfrender Jan 2008

Quantitative-Genetic Variation In Morphological And Physiological Traits Within A Quaking Aspen (Populus Tremuloides) Population, Megan K. Kanaga, Ronald J. Ryel, Karen E. Mock, Michael E. Pfrender

Wildland Resources Faculty Publications

Genetic diversity within populations is an important component of adaptive evolution, and recent research has demonstrated that genetic variation within plant populations can have important ecological effects. In this study, we investigate quantitative-genetic variation in several traits within a quaking aspen (Populus tremuloides Michx.) population. A common garden experiment was planted with replicates of 13 aspen genotypes collected from wet and dry sites within a population in southern Utah, USA. Ten growth, leaf, physiological, and structural traits were measured. There were significant, heritable phenotypic differences among genotypes in every measured trait and differences in 4 of the 10 traits among ...


Modelling Age- And Density-Related Gas Exchange Of Picea Abies Canopies In The Fichtelgebirge, Germany, Eva Falge, John D. Tennhunen, Ronald J. Ryel, Martina Alsheimer, Barbara Köstner Jan 2000

Modelling Age- And Density-Related Gas Exchange Of Picea Abies Canopies In The Fichtelgebirge, Germany, Eva Falge, John D. Tennhunen, Ronald J. Ryel, Martina Alsheimer, Barbara Köstner

Wildland Resources Faculty Publications

Differences in canopy exchange of water and carbon dioxide that occur due to changes in tree structure and density in montane Norway spruce stands of Central Germany were analyzed with a three dimensional microclimate and gas exchange model STANDFLUX. The model was used to calculate forest radiation absorption, the net photosynthesis and transpiration of single trees, and gas exchange of tree canopies. Model parameterizations were derived for six stands of Picea abies (L.) Karst. differing in age from 40 to 140 years and in density from 1680 to 320 trees per hectare. Parameterization included information on leaf area distribution from ...