Life Sciences Commons^™

Rapid Savanna Response To Changing Precipitation Intensity, Ryan S. Berry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate change has the potential to cause large-scale changes in plant growth, biodiversity, and biosphere-climate feedbacks. A pervasive aspect of climate change is that as the atmosphere warms, precipitation events are likely to become less frequent but more intense, because warmer air can hold more water. Larger precipitation events can be expected to change plant productivity and community composition, particularly in semiarid ecosystems such as savannas. Savannas are of particular interest because they are spatially expansive at the global scale, they are important to humans for food production, and they are known to be sensitive to changes in soil water …

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 …

Multi-Scale Environmental Filters And Niche Partitioning Govern The Distributions Of Riparian Vegetation Guilds, Nate Hough-Snee, Brian G. Laub, David M. Merritt, Arin Lexine Long, Lloyd L. Nackley, Brett B. Roper, Joseph Michael Wheaton

Watershed Sciences Faculty Publications

Across landscapes, riparian plant communities assemble under varying levels of disturbance, environmental stress, and resource availability, leading to the development of distinct riparian life-history guilds over evolutionary timescales. Identifying the environmental filters that exert selective pressures on specific riparian vegetation guilds is a critical step in setting baseline expectations for how riparian vegetation may respond to environmental conditions anticipated under future global change scenarios. In this study, we ask: (1) What riparian plant guilds exist across the interior Columbia and upper Missouri River basins? (2) What environmental filters shape riparian guild distributions? (3) How does resource partitioning among guilds influence …

Multi-Scale Environmental Filters And Niche Partitioning Govern The Distributions Of Riparian Vegetation Guilds, Nate Hough-Snee, Brian G. Laub, David M. Merritt, Arin Lexine Long, Lloyd L. Nackley, Brett B. Roper, Joseph Michael Wheaton

Watershed Sciences Faculty Publications

Across landscapes, riparian plant communities assemble under varying levels of disturbance, environmental stress, and resource availability, leading to the development of distinct riparian life-history guilds over evolutionary timescales. Identifying the environmental filters that exert selective pressures on specific riparian vegetation guilds is a critical step in setting baseline expectations for how riparian vegetation may respond to environmental conditions anticipated under future global change scenarios. In this study, we ask: (1) What riparian plant guilds exist across the interior Columbia and upper Missouri River basins? (2) What environmental filters shape riparian guild distributions? (3) How does resource partitioning among guilds influence …

Riparian Vegetation, Colorado River, And Climate: Five Decades Of Spatiotemporal Dynamics In The Grand Canyon With River Regulation, Joel B. Sankey, Barbara Ralston, Paul E. Grams, John C. Schmidt, Laura E. Cagney

Watershed Sciences Faculty Publications

Documentation of the interacting effects of river regulation and climate on riparian vegetation has typically been limited to small segments of rivers or focused on individual plant species. We examine spatiotemporal variability in riparian vegetation for the Colorado River in Grand Canyon relative to river regulation and climate, over the five decades since completion of the upstream Glen Canyon Dam in 1963. Long-term changes along this highly modified, large segment of the river provide insights for management of similar riparian ecosystems around the world. We analyze vegetation extent based on maps and imagery from eight dates between 1965 and 2009, …

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 …

Warming, Competition, And Bromus Tectorum Population Growth Across An Elevation Gradient, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Cheatgrass (Bromus tectorum) is one of the most problematic invasive plant species in North America and climate change threatens to exacerbate its impacts. We conducted a two‐year field experiment to test the effect of warming, competition, and seed source on cheatgrass performance across an elevation gradient in northern Utah. We hypothesized that warming would increase cheatgrass performance, but that warming effects would be limited by competing vegetation and by local adaptation of cheatgrass seed sources. The warming treatment relied on open top chambers, we removed vegetation to assess the effect of competition from neighboring vegetation, and we reciprocally …

Limited Alpine Climatic Warming And Modeled Phenology Advancement For Three Alpine Species In The Northeast United States, Michael L. Davis, Kenneth D. Kimball, Douglas M. Weihrauch, Georgia L. D. Murray, Kenneth Rancourt

Ecology Center Publications

• Premise of the study: Most alpine plants in the Northeast United States are perennial and flower early in the growing season, extending their limitedgrowing season. Concurrently, they risk the loss of reproductive efforts to late frosts. Quantifying long-term trends in northeastern alpine flower phenology and late-spring/early-summer frost risk is limited by a dearth of phenology and climate data, except for Mount Washington, New Hampshire (1916 m a.s.l.).
• Methods: Logistic phenology models for three northeastern US alpinespecies (Diapensia lapponica, Carex bigelowii and Vaccinium vitis-idaea) were developed from 4 yr (2008–2011) of phenology and air temperature measurements from 12 …

Hydrologic And Erosion Responses To Wildfire Along The Rangeland-Xeric Forest Continuum In The Western Us: A Review And Model Of Hydrologic Vulnerability, Christopher Jason Williams, Frederick B. Pierson, Peter R. Robichaud, Jan Boll

Articles

The recent increase in wildfire activity across the rangeland–xeric forest continuum in the western United States has landscape-scale consequences in terms of runoff and erosion. Concomitant cheatgrass (Bromus tectorum L.) invasions, plant community transitions and a warming climate in recent decades along grassland–shrubland–woodland–xeric forest transitions have promoted frequent and large wildfires, and continuance of the trend appears likely if warming climate conditions prevail. These changes potentially increase overall hydrologic vulnerability by spatially and temporally increasing soil exposure to runoff and erosion processes. Plot and hillslope-scale studies demonstrate burning may increase event runoff or erosion by factors of 2–40 over …

Warming, Soil Moisture, And Loss Of Snow Increase Bromus Tectorum’S Population Growth Rate, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Climate change threatens to exacerbate the impacts of invasive species. In temperate ecosystems, direct effects of warming may be compounded by dramatic reductions in winter snow cover. Cheatgrass (Bromus tectorum) is arguably the most destructive biological invader in basins of the North American Intermountain West, and warming could increase its performance through direct effects on demographic rates or through indirect effects mediated by loss of snow. We conducted a two-year experimental manipulation of temperature and snow pack to test whether 1) warming increases cheatgrass population growth rate and 2) reduced snow cover contributes to cheatgrass’ positive response to …

Colorado River Cutthroat Trout Habitat Resistance And Resilience To Climate Change, Kate H. Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Government agencies and private organizations spend large amounts of public money attempting to return ecosystems to a more natural state, which have often been harmed or even destroyed as a result of modern development. Colorado River cutthroat trout, Oncorhyncus clarki pleuriticus, are a subspecies of cutthroat trout. Cutthroat trout live in the Rocky Mountains of the western United States. The population of this particular subspecies has been severely reduced by human actions, and currently only 12% of its historic populations still exist. To improve the condition of cutthroat trout, fisheries professionals and biologists are working to restore natural populations. …

Modeling Usa Stream Temperatures For Stream Biodiversity And Climate Change Assessments, Ryan A. Hill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Stream temperature in one of the most biologically important aspects of water quality, but we lack temperature information for the vast majority of streams within the USA. Stream temperature can be influenced by several types of landscape and waterway alteration including upstream urbanization, agriculture, and reservoir releases. Stream temperatures are also expected to be affected by climate change over the next
century. We need to know how stream temperatures vary naturally, how they are influenced by human activity, and how they will respond to climate changes to effectively manage stream ecosystems. I used data from several thousand streams within the …

Vitals Rates And Seasonal Movements Of Two Isolated Greater Sage-Grouse Populations In Utah's West Desert, Jason D. Robinson, Terry A. Messmer

Human–Wildlife Interactions

Declines in greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) populations in Utah over the last century parallel range-wide trends. However, little is known about the ecology of sage-grouse populations that inhabit Utah’s naturally fragmented habitats. Utah’s West Desert sage-grouse populations occupy sagebrush (Artemisia spp.) habitats that are geographically separated by the Great Salt Lake, and largely confined to the Sheeprock and Deep Creek watersheds. From 2005 to 2006, we monitored sage-grouse that were radio-collared in each watershed to determine the factors affecting the vital rates in these isolated populations. Livestock grazing by domestic cattle was the dominate land use, …

The Effect Of Temperature On Seed Quality And Quantity In Crosses Between European (Populus Tremula) And Hybrid Aspens (P. Tremula X P. Tremuloides), L. Koviuranta, T. Latva-Karjanmaa, P. Pulkkinen

Aspen Bibliography

Hybrid aspen (Populus tremula L. Populus tremuloides Michx.) plantations are expanding in Fennoscandia and the Baltic countries; however, the possible effects of plantations on the native European aspen (P. tremula) and the level of gene flow between European and hybrid aspen have not been investigated. We studied seed quantity and quality in intraspecific and interspecific crosses of the European and hybrid aspens over a two year period. In order to study whether elevated temperatures due to climate change would benefit the species differently, we performed the crosses in different temperatures. In both years, interspecific crosses produced more seeds with higher …

Climate Change And Community Dynamics: A Hierarchical Bayesian Model Of Resource-Driven Changes In A Desert Rodent Community, Glenda M. Yenni

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Predicting effects of climate change on species persistence often assumes that those species are responding to abiotic effects alone. However, biotic interactions between community members may affect species’ ability to respond to abiotic changes. Latent Gaussian models of resource availability using precipitation and NDVI and accounting for spatial autocorrelation and rodent group-level uncertainty in the process are developed to detect differences in seasons, groups, and the experimental removal of one group. Precipitation and NDVI have overall positive effects on rodent energy use as expected, but meaningful differences were detected. Differences in the importance of seasonality when the dominant group was …

Climate Influences The Demography Of Three Dominant Sagebrush Steppe Plants, Harmony Dalgleish, David N. Koons, Melvin Hooten, Corey Moffet, Peter B. Adler

Wildland Resources Faculty Publications

Climate change could alter the population growth of dominant species, leading to profound effects on community structure and ecosystem dynamics. Understanding the links between historical variation in climate and population vital rates (survival, growth, recruitment) is one way to predict the impact of future climate change. Using a unique, long-term dataset from eastern Idaho, we parameterized Integral Projection Models for Pseudoroegneria spicata, Hesperostipa comata, and Artemisia tripartita to identify the demographic rates and climate variables most important for population growth. We described survival, growth and recruitment as a function of genet size using mixed effect regression models that …

Direct And Indirect Effects Of Climate Change On A Prairie Plant Community, Peter B. Adler, James Leiker, Jonathan M. Levine

Wildland Resources Faculty Publications

Background

Climate change directly affects species by altering their physical environment and indirectly affects species by altering interspecific interactions such as predation and competition. Recent studies have shown that the indirect effects of climate change may amplify or counteract the direct effects. However, little is known about the the relative strength of direct and indirect effects or their potential to impact population persistence.

Methodology/Principal Findings

We studied the effects of altered precipitation and interspecific interactions on the low-density tiller growth rates and biomass production of three perennial grass species in a Kansas, USA mixed prairie. We transplanted plugs of each …