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

Digital Commons Network™

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

Environmental Sciences

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 13261 - 13290 of 22729

Full-Text Articles in Entire DC Network

An Examination Of Heritage Resource Internship Experiences And Land Management Agency's Role In Inspiring Emerging Leaders, Carin Vadala Aug 2010

An Examination Of Heritage Resource Internship Experiences And Land Management Agency's Role In Inspiring Emerging Leaders, Carin Vadala

All Dissertations

To address the shortage of people seeking to fill employment vacancies, the land management agencies are using the Student Conservation Association (SCA) and internships as a means of recruiting the next generation of leaders. Yet little research has been conducted on internships in cultural and natural heritage resource parks. This study used a two-phase linear exploratory method to investigate the experiences of cultural and natural heritage resource interns. Additionally, the study sought to determine if and how internships shape vocational, recreational, social and personal identities concerning parks and protected areas. Using significant life experiences, environmental socialization and emerging adulthood theories, …


Effects Of Imperviousness On Family Biotic Index Values In The Southern Appalachian Headwaters And Resulting Extension Education, Jon Calabria Aug 2010

Effects Of Imperviousness On Family Biotic Index Values In The Southern Appalachian Headwaters And Resulting Extension Education, Jon Calabria

All Dissertations

Clear, cool headwater streams in the mountains of North Carolina are inextricably linked to the surrounding landscape. Trickling perennial streams drain precipitation from their catchment and are capable of sustaining excellent water quality to support rich aquatic biodiversity that feeds and beneficially contributes to the stream network below. However, headwater ecosystems can be easily compromised by even seemingly insignificant anthropogenic impacts. Small headwater streams were not mapped until recently, and are now known to be ubiquitous. Although the NC Mountains contain some of the highest headwater streams densities in the nation, they remain very susceptible to changes in the catchments …


Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz Aug 2010

Analytical Solutions For Efficient Interpretation Of Single-Well Push-Pull Tracer Tests, Junqi Huang, John A. Christ, Mark N. Goltz

Faculty Publications

Single-well push-pull tracer tests have been used to characterize the extent, fate, and transport of subsurface contamination. Analytical solutions provide one alternative for interpreting test results. In this work, an exact analytical solution to two-dimensional equations describing the governing processes acting on a dissolved compound during a modified push-pull test (advection, longitudinal and transverse dispersion, first-order decay, and rate-limited sorption/partitioning in steady, divergent, and convergent flow fields) is developed. The coupling of this solution with inverse modeling to estimate aquifer parameters provides an efficient methodology for subsurface characterization. Synthetic data for single-well push-pull tests are employed to demonstrate the utility …


Temporal And Spatial Assessment Of Evaporation, Transpiration, And Soil Moisture Redistribution, Brian M. Bird Aug 2010

Temporal And Spatial Assessment Of Evaporation, Transpiration, And Soil Moisture Redistribution, Brian M. Bird

UNLV Theses, Dissertations, Professional Papers, and Capstones

At a native stand of creosote bush (Larrea tridentata) in North Las Vegas, a rainfall simulation study was conducted over a 12 month period from October 2005 to October 2006. Simulated rainfall occurred during the winter, spring, summer, and fall periods. Rainfall simulation systems were positioned on each of 12 plots, each containing a single creosote bush. Simulated rainfall events occurred at night with multiple short pulses designed to maximize infiltration while minimizing ponding. Yearly simulated rainfall amounts were set at 0, 15, 30 and 60 cm (replicated three times) and were approximately 0, 1.5, 3.0 and 6.0 times the …


Evaluating The Impacts Of Water Conservation Policies On Water Demand, Availability And Outdoor Water Use In The Las Vegas Valley, Kamal Qaiser Aug 2010

Evaluating The Impacts Of Water Conservation Policies On Water Demand, Availability And Outdoor Water Use In The Las Vegas Valley, Kamal Qaiser

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas Valley, located in the arid Southern Nevada region, with a growing population, limited water resources, and a prolonged drought, faces a challenge in meeting its future water needs. Southern Nevada Water Authority (SNWA), the main water management agency in the Valley, is focusing on water conservation to reduce water demand. Current water use is 945 lpcd (250 gpcd) which SNWA aims to reduce to 752 lpcd (199 gpcd) by 2035. Presently the indoor outdoor water use proportion is about 40:60 in the Valley. An important component of the Valley's supply are the return flow credits which SNWA …


Investigation Of Potential Pathways And Multi-Cycle Bioregeneration Of Ion-Exchange Resin Laden With Perchlorate, Mohamadali Sharbatmaleki Aug 2010

Investigation Of Potential Pathways And Multi-Cycle Bioregeneration Of Ion-Exchange Resin Laden With Perchlorate, Mohamadali Sharbatmaleki

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ion-exchange (IX) is possibly the most feasible technology for perchlorate removal and perchlorate-selective and non-selective IX resins are commercially available for this purpose. The use of both resins has shortcomings. Selective resins are incinerated after one time use, and non-selective resins produce a regenerant waste stream that contains high concentration of perchlorate. A process involving directly contacting of spent IX resin containing perchlorate with perchlorate-reducing bacteria (PRB) to bioregenerate the resin has been developed and proven recently. In this process PRB biodegrade perchlorate ions which are attached to the functional groups of the resin.

Although its feasibility has been proven, …


Factors Influencing The Adsorption Of Synthetic Organic Compounds By Carbon Nanotubes In Aquatic Environments, Ting Shao Aug 2010

Factors Influencing The Adsorption Of Synthetic Organic Compounds By Carbon Nanotubes In Aquatic Environments, Ting Shao

All Theses

Carbon nanotubes (CNTs) are allotropes of carbon consisting of sheets of carbon atoms covalently bonded in hexagonal arrays that are seamlessly rolled into a hollow, cy-lindrical shape with both ends rounded by fullerene-like caps. As large amounts of CNTs have been manufactured and significant growth is expected in commercial CNT produc-tion, there is a major concern over their health and environmental risks once they enter into the environment. In aquatic systems, CNTs are likely to adsorb organic chemicals and aggregate as bundles due to their extremely hydrophobic surfaces. The aggregation state of CNTs plays a significant role in their fate …


Metalloporphyrin-Catalyzed Reduction Reactions Of Hexavalent Chromium, Rong Zhang Aug 2010

Metalloporphyrin-Catalyzed Reduction Reactions Of Hexavalent Chromium, Rong Zhang

All Theses

Previous studies have demonstrated that the reduction of oxidized organic and inorganic contaminants could be catalyzed by electron shuttle systems, which generally were biological organic macrocycle complexes with transition metals. Metalloporphyrins (MPs) and their derivatives are well known electron shuttles for many biogeochemical systems. The objective of this research was to study the catalytic capabilities of selected MPs for the reduction of hexavalent chromium (Cr(VI)) in the presence of reducing agents. Zero valent iron (ZVI) was chosen as the primary electron donor in the experimental systems. Protoporphyrin IX (Proto) and Uroporphyrin I (Uro) are naturally occurring porphyrins produced during heme …


Community Ecology Approaches To Amphibian Conservation, Joanna Hawley Aug 2010

Community Ecology Approaches To Amphibian Conservation, Joanna Hawley

All Theses

Amphibian declines have been observed globally for several decades and populations continue to decline in many areas today. Through an extensive literature review of amphibian `impact studies,' I evaluated the use of multiple species, multiple spatial and temporal scales in an effort to ascertain a more complete, community-wide perspective on the causes of amphibian declines as well as management and conservation implications aimed at reversing these declines. Additionally, I performed multivariate analysis of an amphibian community dataset from southern Maine, USA using a multi-species and scalar approach to identify potentially important environmental variables associated with high levels of amphibian reproductive …


Multiple Criteria Decision Analysis For The Selection Of A Land Use Impact Method For A Life Cycle Assessment Of Switchgrass As A Bioenergy Feedstock In The Pee Dee Region Of South Carolina, Joel Kohn Aug 2010

Multiple Criteria Decision Analysis For The Selection Of A Land Use Impact Method For A Life Cycle Assessment Of Switchgrass As A Bioenergy Feedstock In The Pee Dee Region Of South Carolina, Joel Kohn

All Theses

The interactions of a growing human population and increasing demand for food and energy have led to governmental and social pressures encouraging the adoption of biofuels as a substitute for fossil energy sources; however, several potential biofuel feedstocks can compete directly with food products for valuable land area. Life Cycle Assessment (LCA) is a tool that examines the environmental impacts of a product or process and can assist decision makers in the development of policy. The environmental impacts of land use are not well incorporated into LCA. As an emerging field, there is no consensus regarding the best methods by …


Constructed Wetland Treatment Systems For Risk Mitigation Of Energy Derived Waters, Michael Spacil Aug 2010

Constructed Wetland Treatment Systems For Risk Mitigation Of Energy Derived Waters, Michael Spacil

All Theses

Energy derived waters (EDWs) (e.g. petroleum refinery effluents, produced waters) can contain a variety of constituents [e.g. selenium (Se), arsenic (As), low molecular weight organics (LMWOs)]. The overall objective of this research was to provide an approach for remediation of specific constituents of concern in these waters and to measure a relationship between Se removal and abundance of Se reducing microbes. The specific objectives of this research were to: (1) evaluate removal of Se from simulated refinery effluent (SRE) using a pilot-scale constructed wetland treatment system (CWTS); (2) evaluate removal of Se, As, and LMWOs from a generic simulated fresh …


Impact Of Microsparticle Concentration Levels Upon Toxicity Of Phenol To Artemia, Federico Sinche Aug 2010

Impact Of Microsparticle Concentration Levels Upon Toxicity Of Phenol To Artemia, Federico Sinche

All Theses

Plastic pollution constitutes a threat to marine wildlife because of the deleterious impacts ranging from entanglement to ingestion of plastic debris. However, knowledge regarding the impacts of fragmented plastics into micron sizes and their interaction with other toxicants in the marine environment is still limited. In the present study the impact of polystyrene microspheres, 3 µm in diameter, upon toxicity of phenol to the brine shrimp Artemia was investigated in acute toxicity tests. The brine shrimp are employed as a model organism in marine toxicity tests. Phenol is a hydrophobic compound used as an intermediate resin discharged to the environment. …


Developing A Management Tool To Estimate Unmarked Puma (Puma Concolor) Populations With A Remote Camera Array, Megan Pitman Aug 2010

Developing A Management Tool To Estimate Unmarked Puma (Puma Concolor) Populations With A Remote Camera Array, Megan Pitman

All Theses

Puma (Puma concolor) ecological research, puma management, and puma conservation require a technique to efficiently estimate puma populations. Adequate population estimates for pumas are difficult to produce due to natural history characteristics of the species. Remote camera arrays present a promising new tool for surveying cryptic mammals, but techniques for estimating population levels of unmarked animals or species that are difficult to individually identify in photographs are needed. Our goal was to develop techniques to (1) determine the camera effort needed to detect resident pumas with 95% certainty and (2) estimate puma population density for unmarked pumas with a remote …


In Vitro Enabling Technologies For Use In The Aquatic Environment, Colm J. O'Dowd Jul 2010

In Vitro Enabling Technologies For Use In The Aquatic Environment, Colm J. O'Dowd

Doctoral

O’Dowd, C., Mothersill, C.E., Cairns, M.T., Austin, B., Lyng, F.M., McClean, B. and Murphy, J.E.J. Assessing the mitochondrion as a biomarker of fish tissue damage using g radiation as a stress model in vitro.

There is an ever-increasing need for biomarkers to identify toxic stress in the aquatic environment. Such techniques need to be accurate, expeditious, ethical and economical. Typically, in vitro based platforms fit these criteria however many of these systems often undergo ‘assay drift’ and consequently do not fully represent the real-life situation.

In recent years, there has been growing interest in the mitochondrion and its (dys)function …


Unh Eelgrass (Zostera Marina) Monitoring Program For 2010-2014: Quality Assurance Project Plan, Frederick T. Short, Phil Trowbridge Jul 2010

Unh Eelgrass (Zostera Marina) Monitoring Program For 2010-2014: Quality Assurance Project Plan, Frederick T. Short, Phil Trowbridge

PREP Reports & Publications

Eelgrass (Zostera marina) is essential to estuarine ecology because it filters nutrients and suspended particles from water, stabilizes sediments, provides food for wintering waterfowl, and provides habitat for juvenile fish and shellfish, as well as being the basis of an important estuarine food web. Healthy eelgrass both depends on and contributes to good water quality. The UNH Seagrass Ecology Lab, has mapped the distribution of eelgrass every year from 1986 through 2009 in the Great Bay. The entire Great Bay Estuary (Great Bay, Little Bay, tidal tributaries, Piscataqua River, Little Harbor, and Portsmouth Harbor) was mapped by these researchers in …


Baselines Newsletter, No. 6, Summer/Fall 2010, University Of Colorado Boulder. Natural Resources Law Center Jul 2010

Baselines Newsletter, No. 6, Summer/Fall 2010, University Of Colorado Boulder. Natural Resources Law Center

Baselines: The Natural Resources Law Center Newsletter (2007-2011)

No abstract provided.


The Toll Of Toxics: Investigating Environmental Contaminants, Donald Sparling, Barnett A. Rattner, John S. Barclay Jul 2010

The Toll Of Toxics: Investigating Environmental Contaminants, Donald Sparling, Barnett A. Rattner, John S. Barclay

United States Geological Survey: Staff Publications

Two recent events [the Deepwater Horizon oil spill and the Asarco settlement] bring to the fore the work of wildlife toxicologists. Focusing on amphibians, reptiles, birds, and mammals, wildlife toxicology is a component of ecotoxicology--the study of toxic effects caused by natural or synthetic pollutants on living organisms and other constituents of ecosystems (Truhaut 1977). Now a distinct discipline within the wildlife profession-practiced by members of The Wildlife Society's own Wildlife Toxicology Working Group, among others-wildlife toxicology has become increasingly important as human populations and industry have spread, causing contaminants to multiply.

Emerging Environmental Contaminants (EECs) include an array of …


Integrated Fisheries Management Report. West Coast Demersal Scalefish Resource., Department Of Fisheries Western Australia. Jul 2010

Integrated Fisheries Management Report. West Coast Demersal Scalefish Resource., Department Of Fisheries Western Australia.

Fisheries Management Papers

This report on the West Coast Demersal Scalefish fishery is the third in a series of Integrated Fisheries Management (IFM) resource reports required under the Government policy on IFM. Under this policy, the Chief Executive Officer of the Department of Fisheries is required to approve a sustainability report for each fishery, which includes a clear statement on the recommended harvest level.


A Bycatch Action Plan For The Pilbara Fish Trawl Interim Managed Fishery., Department Of Fisheries Western Australia Jul 2010

A Bycatch Action Plan For The Pilbara Fish Trawl Interim Managed Fishery., Department Of Fisheries Western Australia

Fisheries Management Papers

The effect of commercial fishing on bycatch species and the marine ecosystem generally, has emerged as a significant national and international issue. Environmental issues associated with bycatch – including impacts on the ecology of non-target species of fish and wildlife – are important issues to address in reducing the impacts, or potential impacts, of commercial fisheries.

In 1998, the National Standing Committee on Fisheries and Aquaculture developed a national policy on fisheries bycatch. In 1999, the (then) State Minister for Fisheries adopted the national policy as his position on bycatch for Western Australia. The main objective of the policy is …


Scwds Briefs: Volume 26, Number 2 (July 2010), Gary L. Doster , Editor, Scwds Briefs, Michael J. Yabsley Jul 2010

Scwds Briefs: Volume 26, Number 2 (July 2010), Gary L. Doster , Editor, Scwds Briefs, Michael J. Yabsley

Southeastern Cooperative Wildlife Disease Study: Publications

Geese as Sentinels for AIV

Feral Swine Issues Survey

A Spate of Footrot

Some Recent SCWDS Awards

Some Worthwhile Causes
Tom Thorne & Beth Williams Memorial Fund
Ed Couvillion Scholarship Fund
Southeastern Wildlife Health Development Fund

Personnel Changes

Recent SCWDS Publications Available


Interactions: Newsletter Of The Wildlife Society Wildlife Damage Management Working Group, Volume 16 Issue 3, Summer 2010 Jul 2010

Interactions: Newsletter Of The Wildlife Society Wildlife Damage Management Working Group, Volume 16 Issue 3, Summer 2010

TWS Wildlife Damage Management Working Group Newsletter

FINAL COLUMN….. IT’S BEEN FUN. -- Gary San Julian
ADVISORY COMMITTEE BEING FORMED TO AID NWCOA
REBIRTH OF A LEGEND -- THE WILDLIFE SOCIETY BULLETIN IS BACK
WSB CALL FOR PAPERS -- SPECIAL ISSUE ON DEER MANAGEMENT
MEETING ANNOUNCEMENT 17TH ANNUAL WILDLIFE SOCIETY CONFERENCE
1ST ANNUAL NWCOA CONVENTION
MEETING ANNOUNCEMENT 17TH ANNUAL WILDLIFE CONTROL INSTRUCTIONAL SEMINAR
CANDIDATE FOR CHAIR-ELECT -- MICHAEL MENGAK
CANDIDATE FOR CHAIR ELECT -- JAY BOULANGER
CANDIDATE FOR SECRETARY / TREASURER -- CHRIS CROSON
CANDIDATE FOR SECRETARY / TREASURER -- JOHN EISEMANN
CANDIDATE FOR BOARD MEMBER -- WENDY ARJO
CANDIDATE FOR BOARD MEMBER-- TRAVIS DEVAULT
CANDIDATE FOR …


Draft Tampa Bay Interagency Seagrass Monitoring Program Training And Field Manual, Walt Avery, Roger Johansson, J. J. Pacowta Jul 2010

Draft Tampa Bay Interagency Seagrass Monitoring Program Training And Field Manual, Walt Avery, Roger Johansson, J. J. Pacowta

Reports

To insure quality assurance of the data collected among the various agencies, a training session is held each fall immediately prior to baywide TBISP monitoring. The goals of the session are to 1) determine the variability of the data collection among the agencies and to minimize this variability and 2) assess the repeatability of a seagrass investigator in determining species composition, abundance, density, and height. The purpose of this manual is to provide a seagrass researcher with information concerning TBISP protocols and results.


River Sediment Sampling Methods: Causeway Building And Removal, Dillon Dittmer Jul 2010

River Sediment Sampling Methods: Causeway Building And Removal, Dillon Dittmer

Department of Environmental Studies: Undergraduate Student Theses

Abstract The Environmental Protection Agency (EPA) and U.S. Fish and Wildlife Service (USFWS) suspect that causeways have a negative impact on river ecology both when installed and when removed. The Nebraska Department of Roads routinely uses causeways as a tool in the construction and repair of bridges. Although research has not been conducted on the impact of causeway building and removal data has been collected about the impact of dams, causeways, etc. on estuaries. This data is considered subjective and authors often cite sampling methods as a source of error. Currently there are no widely used handheld sampling methods that …


Evaluating Efficacy Of Restoration Techniques, Keys View Road Reconstruction, Joshua Tree National Park, California, U.S.A, Scott R. Abella, E. Cayenne Engel Jul 2010

Evaluating Efficacy Of Restoration Techniques, Keys View Road Reconstruction, Joshua Tree National Park, California, U.S.A, Scott R. Abella, E. Cayenne Engel

Public Policy and Leadership Faculty Research

Keys View Road in Joshua Tree National Park (JOTR) was recently repaved, resulting in a buffer of vegetation and soil disturbance along the road corridor. In order to mitigate the effects of the repaving, JOTR designed an experimental framework to test various revegetation strategies. They outplanted salvaged and nursery grown native plant species in conjunction with vertical mulch in a fully crossed design (outplanting only, vertical mulch only, outplanting + vertical mulch, bare ground) to examine if any of the treatments most efficiently establish native plant communities.


Survey Of Resource Managers Completed On Monitoring And Management Actions For Rare Plants In Arizona And Nevada, Scott R. Abella Jul 2010

Survey Of Resource Managers Completed On Monitoring And Management Actions For Rare Plants In Arizona And Nevada, Scott R. Abella

Public Policy and Leadership Faculty Research

In a collaborative project with Northern Arizona University and more than 35 resource managers in Arizona and Nevada, we completed a survey of monitoring and management activities that are ongoing in these states for conserving populations of rare plants. We sent questionnaires consisting of 16 questions to as many resource managers as possible in these states and had follow-up conversations with several managers willing to share their perspective on ongoing conservation actions. The findings may be interesting for managers to see what issues and management strategies other managers in the same or different regions are grappling with. Results will be …


Mojave Applied Ecology Notes Summer 2010, Scott R. Abella, E. Cayenne Engel Jul 2010

Mojave Applied Ecology Notes Summer 2010, Scott R. Abella, E. Cayenne Engel

Mojave Applied Ecology Notes

Survey of monitoring and management for conservation of rare plants, Roadside restoration techniques in Joshua Tree NP, and an update on renewable energy developments in the Southwestern deserts


Water Current, Volume 42, No. 3, Summer 2010 Jul 2010

Water Current, Volume 42, No. 3, Summer 2010

Water Current Newsletter

Back-to-Back UNL Water Events in October
Mapping Evapotranspiration
Dvorak Temporarily Leaving for Czech Republic; Kuzila to Fill Water Center Director's Post
Meet the Faculty: Chris Henry, P.E., Tsegaye Tadesse, Ph.D.
Bob Daugherty: Man of Vision
Irrigation Management Project Expands
Environmental Science Education: Motive and Opportunity, but Maybe Not the Means?
Recent USGS Funding for NU Research
Tips to Prepare for EPA CAFO Inspections
Annual Water and Natural Resources Tour
EPA Proposes New Permit Requirements for Pesticide Discharge
News Briefs
Invasive Saltcedar, Russian Olive Consume Similar Amounts of Water as Cottonwoods and Willows


Ecology, Stable Isotopes, And Management Of Grassland Songbirds At National Park Service Properties On The Great Plains, Sarah E. Rehme Jul 2010

Ecology, Stable Isotopes, And Management Of Grassland Songbirds At National Park Service Properties On The Great Plains, Sarah E. Rehme

School of Natural Resources: Dissertations, Theses, and Student Research

Grassland ecosystems have been severely reduced and grassland bird populations have experienced consistent declines. National Park Service (NPS) properties on the Great Plains provide breeding habitat for grassland songbirds, though little is known about the quality of this habitat. A short-term study on songbirds at three NPS properties complemented current monitoring, providing an among park comparison addressing grassland bird productivity and fidelity relative to NPS property size. During 2008-2009, I assessed avian species richness, and estimated bird density and grassland songbird nest success. Bird species richness was greatest at small and medium sites, while number of nesting obligate species was …


Chloroacetamid Spray Drift And Leaf Tatters In Hackberry, Ariana P. Miller Jul 2010

Chloroacetamid Spray Drift And Leaf Tatters In Hackberry, Ariana P. Miller

School of Natural Resources: Dissertations, Theses, and Student Research

During the last decade, leaf tatters has been reported in white oak and hackberry across several Midwestern states. Herbicide spray drift studies have shown that chloroacetamides can induce leaf tatters. The objectives of this research were to: 1) identify vulnerable bud developmental stages in hackberry and 2) determine if different commercial chloroacetamides affect severity of leaf tatters. In 2008, a preliminary spray drift experiment was conducted on mature trees from a former hackberry provenance test stand. Acetochlor (Harness), S-metolachlor (Dual II Magnum), and dimethenamid (Outlook) were applied at concentrations approximating 27%, 54%, 81%, or 108% of the recommended field rate. …


The Dickey Bird Scientists Take Charge: Science, Policy, And The Spotted Owl, Thomas R. Wellock Jul 2010

The Dickey Bird Scientists Take Charge: Science, Policy, And The Spotted Owl, Thomas R. Wellock

History Faculty Scholarship

In 1992, the Forest Service adopted a new operating policy, Ecosystem Management, which minimized the agency's timber production goals in favor of a more ecologically balanced view of its responsibilities. In explaining this shift, scholars have dismissed the possibility of internal reform, arguing that the Service could not change without irresistible external pressure from environmental activists and new public values supporting biodiversity. Viewing the Service's shift through the lens of the spotted owl controversy, however, demonstrates the important role agency culture played in instigating bureaucratic change. The Service's evolution stemmed from the rising influence of its scientists in policy formation. …