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Endangered Species Research In Hawaii: The Early Years (1965–87), Michael J. Scott, Cameron B. Kepler Jan 2016

Endangered Species Research In Hawaii: The Early Years (1965–87), Michael J. Scott, Cameron B. Kepler

United States Geological Survey: Staff Publications

Hawaii is an ecologically isolated archipelago 2,500 miles from the nearest continent. Its isolation resulted in a taxonomically unbalanced flora and fauna with remarkable examples of adaptive radiation among those groups of organisms that won the dispersal sweepstakes. It was one of the last oceanic island groups to be populated by humans, about 900 A.D. by Polynesian travelers and in 1778 by Europeans. Relatively recent colonization by humans did not save it, however, from the biodiversity losses suffered by other isolated archipelagos—it only delayed them (Scott and others, 1988; Pratt and others, 2009a).


The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope Jan 2016

The Influence Of A Severe Reservoir Drawdown On Springtime Zooplankton And Larval Fish Assemblages In Red Willow Reservoir, Nebraska, Jason A. Deboer, Christa M. Webber, Taylor A. Dixon, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Reservoirs can be dynamic systems, often prone to unpredictable and extreme waterlevel fluctuations, and can be environments where survival is difficult for zooplankton and larval fish. Although numerous studies have examined the effects of extreme reservoir drawdown on water quality, few have examined extreme drawdown on both abiotic and biotic characteristics. A fissure in the dam at Red Willow Reservoir in southwest Nebraska necessitated an extreme drawdown; the water level was lowered more than 6 m during a two-month period, reducing reservoir volume by 76%. During the subsequent low-water period (i.e., post-drawdown), spring sampling (April-June) showed dissolved oxygen concentration was …


Arsenic In Drinking Water And Lung Cancer Mortality In The United States: An Analysis Based On Us Counties And 30 Years Of Observation (1950-1979)., Hamid Ferdosi, Elisabeth K Dissen, Nana Ama Afari-Dwamena, Ji Li, Rusan Chen, Manning Feinleib, Steven H Lamm Jan 2016

Arsenic In Drinking Water And Lung Cancer Mortality In The United States: An Analysis Based On Us Counties And 30 Years Of Observation (1950-1979)., Hamid Ferdosi, Elisabeth K Dissen, Nana Ama Afari-Dwamena, Ji Li, Rusan Chen, Manning Feinleib, Steven H Lamm

Epidemiology Faculty Publications

Background. To examine whether the US EPA (2010) lung cancer risk estimate derived from the high arsenic exposures (10-934 µg/L) in southwest Taiwan accurately predicts the US experience from low arsenic exposures (3-59 µg/L). Methods. Analyses have been limited to US counties solely dependent on underground sources for their drinking water supply with median arsenic levels of ≥3 µg/L. Results. Cancer risks (slopes) were found to be indistinguishable from zero for males and females. The addition of arsenic level did not significantly increase the explanatory power of the models. Stratified, or categorical, analysis yielded relative risks that hover about 1.00. …


Bibliographia Phytosociologica Et Floristica Mongolia: Pars Iv, Werner Hilbig Jan 2016

Bibliographia Phytosociologica Et Floristica Mongolia: Pars Iv, Werner Hilbig

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

In Ergänzung zu den bisherigen drei Teilen der Bibliographie vegetationskundlicher, vegetationsökologischer, floristischer und pflanzengeographischer Arbeiten über die Mongolei wird in dieser Arbeit Teil IV der Bibliographie vorgelegt. Er umfasst im Wesentlichen den Zeitraum 2007 bis 2014. Auch Publikationen zur Vegetationsgeschichte und zum botanischen Naturschutz werden berücksichtigt.

English summary:

In addition to the hitherto existing three parts of the bibliography of geobotanical, ecological, floristic and plant-geographical papers on Mongolia the part IV of the bibliography is given. It comprises in the main point the period from 2007 until 2014. In addition, publications on vegetation history and botanical nature protection are considered.


Late Holocene Expansion Of Ponderosa Pine (Pinus Ponderosa) In The Central Rocky Mountains, Usa, Jodi R. Norris, Julio L. Betancourt, Stephen T. Jackson Jan 2016

Late Holocene Expansion Of Ponderosa Pine (Pinus Ponderosa) In The Central Rocky Mountains, Usa, Jodi R. Norris, Julio L. Betancourt, Stephen T. Jackson

United States National Park Service: Publications

Aim: Ponderosa pine (Pinus ponderosa) experienced one of the most extensive and rapid post-glacial plant migrations in western North America. We used plant macrofossils from woodrat (Neotoma) middens to reconstruct its spread in the Central Rocky Mountains, identify other vegetation changes coinciding with P. ponderosa expansion at the same sites, and relate P. ponderosa migrational history to both its modern phylogeography and to a parallel expansion by Utah juniper (Juniperus osteosperma).

Location: Central Rocky Mountains, Wyoming and Montana, and Black Hills, Wyoming and South Dakota, USA.

Methods: Plant macrofossils were analysed in …


Changes In Wetland Conditions And Wetland Plant Communities In The Prairie Pothole Region After 50 Years, Ryann Cressey Jan 2016

Changes In Wetland Conditions And Wetland Plant Communities In The Prairie Pothole Region After 50 Years, Ryann Cressey

Electronic Theses and Dissertations

Wetlands in Stutsman County, North Dakota were revisited after 50 years to assess changes in wetland conditions and plant communities within wetland zones in the Prairie Pothole Region. In 1961-1966, Robert E. Stewart and Harold A. Kantrud conducted a study to investigate the relationship of wetland plant communities to variations of water permanence and chemistry on three study areas: Crystal Springs, Cottonwood, and Mt. Moriah. Within in this region, a severe drought occurred in 1988- 1992 followed by the longest deluge starting in 1993 with wetlands still impacted today. In 2013 and 2014, I revisited 80 of the original wetlands …


Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta Jan 2016

Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta

Electronic Theses and Dissertations

Ferruginous hawks (Buteo regalis) are a grassland and shrubland obligate nesting raptor and prefer lightly grazed pasture or idle areas for nesting. Their population reportedly declines in number if more than 30% of an area is cultivated and they rarely nest in areas dominated by croplands. Golden eagles (Aquila chrysaetos) are long-lived raptors with high nest-site fidelity and relatively low reproductive success. Population trends of golden eagles in western United States are unclear although long-term monitoring of populations shows declines in occupancy and breeding performance. Northern harriers (Circus cyaneus) prefer relatively open grasslands and …


Current Status Of Falcon Populations In Saudi Arabia, Albara M. Binothman Jan 2016

Current Status Of Falcon Populations In Saudi Arabia, Albara M. Binothman

Electronic Theses and Dissertations

Falcons (Falco spp.) are widely used for falconry in the countries of the Middle East. During the 2015 breeding season, we surveyed historic and active nest sites of Barbary (Falco pelegrinoides pelegrinoides) and Lanner (F. biarmicus) Falcons in Saudi Arabia. Field and questionnaire surveys were conducted and personal contact with falconers was made to document the current distribution and price changes for Lanner Falcons, Barbary Falcons, Saker Falcons (F. cherrug), Peregrine Falcons (F. peregrinus), Gyrfalcons (F. rusticolus), and Hybrid Falcons in Saudi Arabia. We categorized our survey into three geographic groups; southwest (A), northwest (B), and central (C) regions of …


Solar Irradiation Estimator Based On A Self-Calibrated Reference Solar Cell, Touria Hassboun, Lhoussain El Bahir, Youness Aite Driss, Mustapha El Adnani Jan 2016

Solar Irradiation Estimator Based On A Self-Calibrated Reference Solar Cell, Touria Hassboun, Lhoussain El Bahir, Youness Aite Driss, Mustapha El Adnani

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper we propose a concept for estimating solar irradiation based on measurements of the current, voltage, and temperature of a photovoltaic (PV) cell. The estimation of the irradiation is obtained by processing these measurements using a PV cell mathematical model combined with a PI controller. Since the PV cell current is very sensitive to the irradiance level, the principle of the method is to force the model to reproduce the same current as that measured on the cell by applying an appropriate irradiance as input, for measured temperature and voltage. The appropriate irradiance, which is the output of …


Patuxent’S Long-Term Research On Wolves, David L. Mech Jan 2016

Patuxent’S Long-Term Research On Wolves, David L. Mech

United States Geological Survey: Staff Publications

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species. Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota. Endangered Species Act protection of the wolf fostered its …


Evaluating Survival Of Released Ranched American Alligator In Coastal Louisiana, Kristy Durham Capelle Jan 2016

Evaluating Survival Of Released Ranched American Alligator In Coastal Louisiana, Kristy Durham Capelle

LSU Master's Theses

Since 1986, Louisiana’s American alligator (Alligator mississippiensis) ranching program has required the release of alligators produced from eggs collected from wild nests to maintain wild populations. This project assessed long-term harvest data (1991-2010s) to estimate survival of released alligators. First, wildlife and fishery harvest models and general inter-disciplinary survival models were evaluated to determine best fit to the data. Second, once the best fitting model was selected, release length, precipitation and temperature from release sites, and an index of hunter effort were added to investigate influences on survival estimates. Release length was included because over time the proportion and size …


A Step In The Right Direction: Streambank Restoration Efforts At The Botanical Garden Of The Ozarks, Dylan S. Milholen, Madison Brown, Steven Thao, Lisa S. Wood Jan 2016

A Step In The Right Direction: Streambank Restoration Efforts At The Botanical Garden Of The Ozarks, Dylan S. Milholen, Madison Brown, Steven Thao, Lisa S. Wood

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The Botanical Garden of the Ozarks (BGO) is a unique destination in Northwest Arkansas that draws more than 80,000 visitors a year. While the BGO manages low-input practices, run-off from pesticide application and synthetic fertilizers containing phosphorus and nitrogen are of concern to water quality, habitat, and overall ecological interactions of the BGO streambanks and adjacent Hilton Creek, which flows directly into Lake Fayetteville. One way to reduce pollution to waterbodies is through the use of riparian buffers. This project sought to establish a riparian buffer immediately adjacent to a portion of Hilton Creek in an effort to improve ecological …


Determining The Effects Of Non-Native Brook Stickleback (Cualea Inconstans) On The Lentic Systems At Turnbull National Wildlife Refuge, Cheney, Wa, Jenae N. Yri Jan 2016

Determining The Effects Of Non-Native Brook Stickleback (Cualea Inconstans) On The Lentic Systems At Turnbull National Wildlife Refuge, Cheney, Wa, Jenae N. Yri

EWU Masters Thesis Collection

"The introduction of non-native fishes can cause trophic cascades in freshwater habitats; these effects may be amplified in ephemeral/temporary habitats. Non-native brook stickleback fishes (Culaea inconstans) were first documented on the Turnbull National Wildlife Refuge (WA) in 1999 and are now present in many portions of the refuge. The consequences of their presence on the refuge's perennial/permanent and temporary habitats are poorly understood. Therefore, the purpose of my project was to determine if brook stickleback are affecting habitat characteristics that are important for waterfowl nesting success. From April-August 2015, I compared the macro invertebrate and macrophyte community characteristics, fingernail clam …


Geospatial Approaches To Support Pelagic Conservation Planning And Adaptive Management, L. M. Wedding, Sara M. Maxwell, D. Hyrenbach, D. C. Dunn, J. J. Roberts, D. Briscoe, E. Hines, P. N. Halpin Jan 2016

Geospatial Approaches To Support Pelagic Conservation Planning And Adaptive Management, L. M. Wedding, Sara M. Maxwell, D. Hyrenbach, D. C. Dunn, J. J. Roberts, D. Briscoe, E. Hines, P. N. Halpin

Biological Sciences Faculty Publications

Place-based management in the open ocean faces unique challenges in delineating boundaries around temporally and spatially dynamic systems that span broad geographic scales and multiple management jurisdictions, especially in the 'high seas'. Geospatial technologies are critical for the successful design of pelagic conservation areas, because they provide information on the spatially and temporally dynamic oceanographic features responsible for driving species distribution and abundance in the open ocean, the movements of protected species, and the spatial patterns of distribution of potential threats. Nevertheless, there are major challenges to implementing these geospatial approaches in the open ocean. This Theme Section seeks to …


Modern Foraminiferal Assemblages Of The Denmark Strait, Laura Larocca Jan 2016

Modern Foraminiferal Assemblages Of The Denmark Strait, Laura Larocca

Dissertations and Theses

Foraminifera occupy a geological range from the early Cambrian to the present day. Their well preserved shells, high relative abundance, and short response time to changing environmental conditions make foraminifera ideal proxies for environmental change. Benthic foraminifera are a valuable but poorly understood paleobiological proxy for the reconstruction of environmental conditions on continental shelves occupied by arctic and subarctic waters. This study identifies, examines, and quantifies calcareous benthic foraminiferal faunas from a sediment core taken from the Denmark Strait. Our analysis of three-thousand individuals from ten discrete samples aim to provide a better understanding of the modern patterns of foraminiferal …


Trade-Offs Between Three Forest Ecosystem Services Across The State Of New Hampshire, Usa: Timber, Carbon, And Albedo, David A. Lutz, Elizabeth A. Burakowski, Mackenzie B. Murphy, Mark E. Borsuk Jan 2016

Trade-Offs Between Three Forest Ecosystem Services Across The State Of New Hampshire, Usa: Timber, Carbon, And Albedo, David A. Lutz, Elizabeth A. Burakowski, Mackenzie B. Murphy, Mark E. Borsuk

Dartmouth Scholarship

Forests are more frequently being managed to store and sequester carbon for the purposes of climate change mitigation. Generally, this practice involves long-term conservation of intact mature forests and/or reductions in the frequency and intensity of timber harvests. However, incorporating the influence of forest surface albedo often suggests that long rotation lengths may not always be optimal in mitigating climate change in forests characterized by frequent snowfall. To address this, we investigated trade-offs between three ecosystem services: carbon storage, albedo-related radiative forcing, and timber provisioning. We calculated optimal rotation length at 498 diverse Forest Inventory and Analysis forest sites in …


Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters Jan 2016

Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters

University Faculty and Staff Publications

Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent …


Impacts Of Environmental Changes To The Middle Rio Grande Landscape On Ysleta Del Sur Pueblo's Cultural And Cermonial Sustainability, Andrea L. Everett Jan 2016

Impacts Of Environmental Changes To The Middle Rio Grande Landscape On Ysleta Del Sur Pueblo's Cultural And Cermonial Sustainability, Andrea L. Everett

Open Access Theses & Dissertations

Given future climate scenarios, this Thesis investigates how plausible climate changes will further impact the Native American community of Ysleta del Sur Pueblo's (Tiguas) cultural continuity and access to riparian ecosystem services along the Rio Grande River (specific to Tigua tradition; riparian vegetation used in ceremony, i.e. Gooding's and Coyote willow). The project aims to (1) describe and understand the relationship between regional climatic changes, anthropogenic changes, and major events in Tigua history, (2) identify rates and patterns of riparian vegetation changes, (3) evaluate impacts on cultural and provisioning ecosystem services relevant to Tigua culture, and relate these to climate …


Drinking Water And Autism: Using Spatial Cluster Detection To Explore Patterns Of Autism Cases In Lane County, Oregon, Sherry Sandreth Jan 2016

Drinking Water And Autism: Using Spatial Cluster Detection To Explore Patterns Of Autism Cases In Lane County, Oregon, Sherry Sandreth

Walden Dissertations and Doctoral Studies

Autism Spectrum Disorders (ASD) are a complex array of neurological disorders with a diverse presentation, multiple etiologies, and long-term ramifications. Prevalence of ASD in the United States is about 1 in 50 children as of 2013, making it a significant public health problem. The etiology is not understood, and it is widely accepted that it is multicausal, with genetic and environmental influences. Prior research suggests an association between water source and ASD. Contaminants such as lead, arsenic, mercury, pharmaceuticals and pesticides found in water are associated with developmental disorders suggesting that a systematic review focused on water source was warranted. …


Valuing Natural Space And Landscape Fragmentation In Richmond, Va, Lee Wyatt Carpenter Jan 2016

Valuing Natural Space And Landscape Fragmentation In Richmond, Va, Lee Wyatt Carpenter

Theses and Dissertations

Hedonic pricing methods and GIS (Geographic Information Systems) were used to evaluate relationships between sale price of single family homes and landscape fragmentation and natural land cover. Spatial regression analyses found that sale prices increase as landscapes become less fragmented and the amount of natural land cover around a home increases. The projected growth in population and employment in the Richmond, Virginia region and subsequent increases in land development and landscape fragmentation presents a challenge to sustaining intact healthy ecosystems in the Richmond region. Spatial regression analyses helped illuminate how land cover patterns influence sale prices and landscape patterns that …


Invertebrate Drift In The Upper Columbia River With Implications For Young-Of-The-Year White Sturgeon, Ryan W. Reihart Jan 2016

Invertebrate Drift In The Upper Columbia River With Implications For Young-Of-The-Year White Sturgeon, Ryan W. Reihart

EWU Masters Thesis Collection

"White sturgeon (Acipenser transmontanus) in the upper Columbia River have been in decline for over 60 years and are listed as critically endangered by the International Union for Conservation of Nature. Annual spawning produces dispersing larvae; however, recruitment into the juvenile age class has not occurred since the early 1970s. One hypothesis to explain this failure in recruitment is that larvae may not find adequate prey. Little is known about diet and prey availability for white sturgeon larvae, especially in Lake Roosevelt, a reservoir of the Columbia River. The Spokane Tribe of Indians collected littoral and mid-channel benthic drift samples …


Small-Scale Biogeographic Patterns Of Benthic Bacterial And Ciliate Communities In The Saline Ponds Of Lake Macleod, North-Western Australia, Christopher Kavazos Jan 2016

Small-Scale Biogeographic Patterns Of Benthic Bacterial And Ciliate Communities In The Saline Ponds Of Lake Macleod, North-Western Australia, Christopher Kavazos

Theses: Doctorates and Masters

This biogeographical thesis tests for the presence of taxa-area and distance-decay relationships, which are common among macrobionts, in prokaryotic (bacterial) and micro-eukaryotic (ciliate) communities. Microbial biogeographical patterns may be distinct because of the high abundances, diversity and dispersal capabilities of microbes, in comparison to macrobionts. The Northern Ponds of Lake MacLeod, north-western Australia, provide an ideal location to address this topic, because the ponds are effectively hydrogeomorphologically identical, other than in surface area, and biotic histories can be assumed to differ only according to distance of separation. This means that hypotheses concerning species-sorting and neutral processes on microbial assemblages can …


Seasonal Habitat Selection Of The North American Porcupine (Erethizon Dorsatum) In A Coastal Dune Forest, Cara L. Appel Jan 2016

Seasonal Habitat Selection Of The North American Porcupine (Erethizon Dorsatum) In A Coastal Dune Forest, Cara L. Appel

Cal Poly Humboldt theses and projects

Wildlife-habitat relationship studies are important for understanding the factors that determine where species occur in space and time. Habitat selection by generalist species should be studied on fine spatial and temporal scales to avoid masking important differences between seasons, localities, or orders of selection. I conducted the first study of habitat use and general ecology of North American porcupines (Erethizon dorsatum) in a coastal dune environment. Specifically, I assessed changes in body mass, home range size, and habitat selection in relation to the potential for seasonal nutritional and survival bottlenecks as reported elsewhere. Although they are considered generalists, …


Quantifying The Adaptive Cycle, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Lance H. Gunderson, Olle Hjerne, Monika Winder Dec 2015

Quantifying The Adaptive Cycle, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Lance H. Gunderson, Olle Hjerne, Monika Winder

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term …


Utilizing Ecological Connectivity In California Desert Wilderness Preservation, Lauren Kahal Dec 2015

Utilizing Ecological Connectivity In California Desert Wilderness Preservation, Lauren Kahal

Master's Projects and Capstones

The Wilderness Act of 1964 gave the federal land management agencies—the National Park Service, United States Forest Service, U.S Fish and Wildlife Service, and Bureau of Land Management—the authority to identify, propose, and manage lands as wilderness. Wilderness, once approved by Congress for inclusion in the National Wilderness Preservation System, is offered the highest form of land preservation in the nation. However, the wilderness identification process used by the implementing agencies is based on a half-century old statute with an aging definition of wilderness. While designated wilderness can protect the plant and wildlife communities within its borders from direct anthropogenic …


Connectivity Of Coastal And Oceanic Ecosystems: Pelagic Habitat Use By Juvenile Reef Fishes In The Gulf Of Mexico, Katie Bowen Dec 2015

Connectivity Of Coastal And Oceanic Ecosystems: Pelagic Habitat Use By Juvenile Reef Fishes In The Gulf Of Mexico, Katie Bowen

HCNSO Student Theses and Dissertations

The assemblage structure, abundance, biomass, and vertical distribution of juvenile reef fishes in the offshore pelagic habitat of the northern Gulf of Mexico are described as part of the NOAA-supported Offshore Nekton Sampling and Analysis Program. The results presented here are from a 3-month, continuous sampling series in 2011 in which discrete depth strata from 0 to 1500 m were sampled using a 10-m2 MOCNESS midwater trawl. This is the first study to examine pelagic juvenile reef fish distributions across the entire oceanic northern Gulf of Mexico seaward of the continental shelf break after the Deepwater Horizon Oil Spill. …


Effects Of Short-Term Soil Conditioning By Cheatgrass And Western Wheatgrass, James J. O'Connor, Janet S. Prevey Dec 2015

Effects Of Short-Term Soil Conditioning By Cheatgrass And Western Wheatgrass, James J. O'Connor, Janet S. Prevey

The Prairie Naturalist

The exotic grass Bromus tectorum (cheatgrass) is a ubiquitous invader in the western USA. Cheatgrass is a proficient competitor, frequently displacing native plants, forming monotypic stands and reducing biodiversity in ecosystems it invades. Our experiment tested whether short-term soil modification by cheatgrass and a predominant native grass, Pascopyrum smithii (western wheatgrass), affected subsequent growth of both species. We compared productivity of cheatgrass and western wheatgrass by harvesting aboveground biomass of plants grown in either cheatgrass- or western wheatgrass-conditioned soils over two simulated growing seasons. Results indicated that cheatgrass soils do not inhibit the productivity of the native grass, but do …


Remembering Paul B. Kannowski, Robert Seabloom Dec 2015

Remembering Paul B. Kannowski, Robert Seabloom

The Prairie Naturalist

I am saddened to report that Dr. Paul Kannowski passed away 3 September 2015, succumbing to cancer. He was 88. A native of Grand Forks, Paul attended the University of North Dakota for his B.S. and M.S. degrees, and the University of Michigan for his Ph.D. He joined the University of North Dakota Biology Department in 1957, retiring in 1990 after 33 years of service

Paul chaired UND’s Biology Department twice, totaling 13 years, considered to be a remarkable achievement by many of us who have been exposed to that task! His leadership was instrumental in the nearly exponential growth …


Ecosystem Response To Recent Climate Change In Alpine Environments, Patrick Shawn Sawyer Dec 2015

Ecosystem Response To Recent Climate Change In Alpine Environments, Patrick Shawn Sawyer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recent variations in meteorological conditions indicate the earth’s climate is changing in ways that can impact delicate ecological balances in sensitive regions. These impacts threaten the essential services provided by such ecosystems. Determining how climate changes are affecting the biosphere is essential to adapt and mitigate harmful consequences. In order to mitigate the negative effects of climate change and adapt to shifting ecological resource constraints, it is imperative to locate such changes and determine vulnerability of ecological resources to changing environmental conditions.

Identifying climate driven ecological changes faces numerous challenges given the reliance on vegetation indices as the primary measure …


Modelling Water Uptake Provides A New Perspective On Grass And Tree Coexistence, Michael G. Mazzacavallo, Andrew Kulmatiski Dec 2015

Modelling Water Uptake Provides A New Perspective On Grass And Tree Coexistence, Michael G. Mazzacavallo, Andrew Kulmatiski

Wildland Resources Faculty Publications

Root biomass distributions have long been used to infer patterns of resource uptake. These patterns are used to understand plant growth, plant coexistence and water budgets. Root biomass, however, may be a poor indicator of resource uptake because large roots typically do not absorb water, fine roots do not absorb water from dry soils and roots of different species can be difficult to differentiate. In a sub-tropical savanna, Kruger Park, South Africa, we used a hydrologic tracer experiment to describe the abundance of active grass and tree roots across the soil profile. We then used this tracer data to parameterize …