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 13441 - 13470 of 22729

Full-Text Articles in Entire DC Network

The Influence Of Mechanical Circulation On Water Column Stability And Dissolved Oxygen In Stratified Lakes, Paal Engebrigtsen Apr 2010

The Influence Of Mechanical Circulation On Water Column Stability And Dissolved Oxygen In Stratified Lakes, Paal Engebrigtsen

Civil & Environmental Engineering Theses & Dissertations

Surface circulators have been used in wastewater and industrial lagoons for many years, but only recently have they been designed for lakes and reservoirs as a water quality management tool. Their relatively low capital investment and operational costs make them an attractive chemical free option for ameliorating the symptoms of eutrophication. Little research has been conducted on their effectiveness in impacting water quality. Today many lake managers are waiting for independent research on surface circulators' performance before installing such systems.

The Occoquan Reservoir was the primary site for a study conducted to examine the influence of surface circulation on water …


A Test Of The Area Of Refuge Hypothesis In Indo-Pacific Marine Biogeography, Jonnell C. Sanciangco Apr 2010

A Test Of The Area Of Refuge Hypothesis In Indo-Pacific Marine Biogeography, Jonnell C. Sanciangco

Biological Sciences Theses & Dissertations

Many hypotheses have been proposed to explain the marine biogeographic patterns of species richness of the Indo-Pacific. One of these hypotheses suggests that available habitat area is the main predictor of species richness. This is the basis for the area of refuge hypothesis that attempts to explain the global maxima of species richness found in the Coral Triangle, the area encompassing mostly the Philippines, Indonesia, and Malaysia. This species-area effect also has habitat heterogeneity as a potential component. The purpose of this study is to test the effects of habitat availability predictors, such as shallow water area and coastline length …


Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Quarterly Progress Report, Period Ending March 31, 2010, Margaret N. Rees Mar 2010

Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Quarterly Progress Report, Period Ending March 31, 2010, Margaret N. Rees

Wildlife Monitoring

Project 1. Relict Leopard Frog Monitoring, Management, and Research

  • All milestones and deliverables are on schedule
  • Translocation program initiated for this year with egg mass collections in early spring
  • Tadpole rearing underway, first releases schedule for the end of March 2010
  • Diurnal egg mass surveys were completed at all sites
  • Nocturnal surveys initiated and in progress
  • Continuing mark-recapture efforts at Blue Point Spring initiated for spring season
  • Data transferred to County completed

Project 2. Bald Eagle Winter Monitoring and Evaluation

  • Project has essentially been completed
  • All final report deliverables were completed
  • Although not specified in the scope of work for …


Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending March 30, 2010, Margaret N. Rees Mar 2010

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending March 30, 2010, Margaret N. Rees

Limnological Studies

Project 1

• Technical assistance with the implementation of the Interagency Monitoring Action Plan (I-MAP) for Quagga Mussels is ongoing. Three sampling events took place this quarter and analysis of all samples (fall 2009 – spring 2010) is underway.

• Two graduate students are undergoing necessary training for the two small-scale research projects funded by this task agreement. Sampling is anticipated to begin in June 2010.

• The quarterly Interagency Quagga Mussel Meeting was held in March 2010.

Project 2

• Protocols relevant to the Long-term Limnological Aquatic Resource Monitoring and Research Plan (Plan) for Lakes Mead and Mohave have …


Gasoline: The Achilles' Heel Of U. S. Energy Security, Robert W. Weaver Mar 2010

Gasoline: The Achilles' Heel Of U. S. Energy Security, Robert W. Weaver

United States Department of Energy: Publications

The United States must balance securing our energy future with protecting our environment from climate change. A holistic approach is required to solve this complex problem. We must reduce demand for petroleum, improve energy efficiency, and develop feasible alternative energy solutions to include emission capture technologies.

The United States remains the largest consumer of energy products in the world and is the second leading producer of green house gas (GHG) emissions. Our dependence on imported petroleum is undermining our control of our national security interests. Petroleum comprises 63% of the United States’ energy consumption, with the transportation sector accounting for …


Data Summary From The Tampa Bay Interagency Seagrass Monitoring Program Through Year 2008, Walt Avery, Roger Johansson Mar 2010

Data Summary From The Tampa Bay Interagency Seagrass Monitoring Program Through Year 2008, Walt Avery, Roger Johansson

Reports

In 1997, the TBEP coordinated the creation of a bay-wide fixed transect seagrass monitoring program. The primary goal of the program is to document temporal and spatial changes in seagrass species composition, abundance, and distribution along a depth gradient. Several bay area agencies committed personnel and equipment to the program. Data collection from 60 transects began in 1998. Currently, 62 transects are monitored due to revisions in transect selection and location. This paper presents a general summary of Tampa Bay seagrass trends from 1998-2008


Evaluation Of Alternative Technologies To Supply Drinking Water To Marines In Forward Deployed Locations, Derek R. George Mar 2010

Evaluation Of Alternative Technologies To Supply Drinking Water To Marines In Forward Deployed Locations, Derek R. George

Theses and Dissertations

With recent increases, there are approximately 20,000 Marines deployed in the Helmand Province of Afghanistan. The cost of delivering bottled water to the troops is rapidly becoming unsustainable and convoys delivering bottled water are vulnerable to Improvised Explosive Devices (IEDs). Currently, raw water from indigenous sources, which has chemical and microbiological contaminants, is treated with reverse osmosis (RO), but only used for hygiene, with bottled water used for drinking. Due to the economic costs and risks to life of providing bottled water, decision-makers need to evaluate technology alternatives to treat raw water to supply safe drinking water. In this study, …


An Evaluation Of A Networked Radiation Detection System, Leif A. Hansen Mar 2010

An Evaluation Of A Networked Radiation Detection System, Leif A. Hansen

Theses and Dissertations

First responders assess a Nuclear/Radiological (NUCRAD) event in a timely and accurate manner by creating a site characterization that reflects the location of various levels of contamination based on their instruments’ readings. The survey team experiences difficulty in accurately recording this critical data due to the challenge of operating multiple devices and communicating the devices’ readings to other survey members. First responders produce a representation of the contamination or activity on a map that contain rings outlining the levels of activity and/or single locations of a single activity. Recently, several agencies began creating software programs that record a first responder’s …


Environmental Life Cycle Assessment Of Coal-Biomass To Liquid Jet Fuel Compared To Petroleum-Derived Jp-8 Jet Fuel, Wayne C. Kinsel Mar 2010

Environmental Life Cycle Assessment Of Coal-Biomass To Liquid Jet Fuel Compared To Petroleum-Derived Jp-8 Jet Fuel, Wayne C. Kinsel

Theses and Dissertations

The United States (U.S.) imported 57% of the petroleum products that it consumed in 2008. The Department of Defense (DOD) and in particular, the United States Air Force (USAF), consumes a large amount of oil to support the mission of defending the U.S. According to the USAF energy policy, by 2016, the Air Force (AF) must be prepared to cost competitively acquire 50% of its domestic aviation fuel requirement via an alternative fuel blend in which the alternative component is derived from domestic sources produced in a manner that is “greener” than fuels produced from conventional petroleum. This study employed …


Modeling The Fate Of Groundwater Contaminants Resulting From Leakage Of Butanol-Blended Fuel, Khai H. Vuong Mar 2010

Modeling The Fate Of Groundwater Contaminants Resulting From Leakage Of Butanol-Blended Fuel, Khai H. Vuong

Theses and Dissertations

Fuel spills and leaks from storage tanks can contaminate groundwater. Typically in groundwater, hazardous aromatic hydrocarbons like benzene are attenuated through natural processes. However, it is possible that adding butanol to gasoline will interfere with these natural attenuation processes, so that spills and leaks of alternative fuels containing biobutanol may result in more persistent hazardous aromatic hydrocarbon plumes. This effect has already been observed with ethanol, which is currently added to gasoline. A numerical model was developed to simulate the subsurface fate and transport of butanol-blended fuel to assess the potential impacts of butanol on the natural attenuation of benzene. …


Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Executive Summary And Concise Statement Of Accomplishments, Limnological Assistance For Lake Mead National Recreation Area Mar 2010

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Executive Summary And Concise Statement Of Accomplishments, Limnological Assistance For Lake Mead National Recreation Area

Limnological Studies

Limnological Assistance for the Lake Mead National Recreation Area in Meeting the Challenge of the Water 2025 Initiative was a Southern Nevada Public Land Management Act (SNPLMA)-funded project. It was implemented by the University of Nevada, Las Vegas (UNLV) Public Lands Institute (PLI) cooperatively with the UNLV Department of Environmental and Occupational Health and the UNLV Harry Reid Center for Environmental Studies on behalf of and in cooperation with the National Park Service, Lake Mead National Recreation Area (Lake Mead NRA).


Adverse Outcome Pathways And Ecological Risk Assessment: Bridging To Population-Level Effects, Vincent J. Kramer, Matthew A. Etterson, Markus Hecker, Cheryl A. Murphy, Guritno Roesijadi, Daniel J. Spade, Julann A. Spromberg, Magnus Wang, Gerald T. Ankley Mar 2010

Adverse Outcome Pathways And Ecological Risk Assessment: Bridging To Population-Level Effects, Vincent J. Kramer, Matthew A. Etterson, Markus Hecker, Cheryl A. Murphy, Guritno Roesijadi, Daniel J. Spade, Julann A. Spromberg, Magnus Wang, Gerald T. Ankley

United States Environmental Protection Agency: Publications

Maintaining the viability of populations of plants and animals is a key focus for environmental regulation. Population-level responses integrate the cumulative effects of chemical stressors on individuals as those individuals interact with and are affected by their conspecifics, competitors, predators, prey, habitat, and other biotic and abiotic factors. Models of population-level effects of contaminants can integrate information from lower levels of biological organization and feed that information into higher-level community and ecosystem models. As individual-level endpoints are used to predict population responses, this requires that biological responses at lower levels of organization be translated into a form that is usable …


Interpretive Programs For Natural Resource Interpretation At Glacier Point, Yosemite National Park, California, Shannon Brianne Glendenning Mar 2010

Interpretive Programs For Natural Resource Interpretation At Glacier Point, Yosemite National Park, California, Shannon Brianne Glendenning

Natural Resources Management and Environmental Sciences

This guide to Natural Resource Interpretation in the Glacier Point Region of Yosemite National Park, California was developed over three summers of research and implementation. The range of programs developed to inform the public about the regional and local natural resources are: formal, semi-formal, ranger led hikes and walks, activity based programs, and informal visitor contacts. The programs were designed to inform park visitors about the natural, social, and historical resources in the region. The overall objective is to connect the visitors with the marvels and wonders of the natural resources at Glacier Point in Yosemite National Park, California. This …


A Climate Action Plan For Bucknell University, Wendy Chou, Dina El-Mogazi, Dennis Hawley Mar 2010

A Climate Action Plan For Bucknell University, Wendy Chou, Dina El-Mogazi, Dennis Hawley

Technical Reports

The accelerating pace of human-influenced climate change and our growing awareness of its negative public-health, environmental, and economic consequences compel decisive action. In recent years, many institutions of higher education have taken leadership roles to promote sustainability and climate neutrality at the campus level. In January 2008, Bucknell University became a signatory to the American Colleges and University Presidents Climate Commitment (ACUPCC). Under this agreement, Bucknell is required to prepare a comprehensive inventory of greenhouse gas emissions by May 2009, to update the inventory every other year thereafter, and to implement tangible emissions-reducing actions in the short-term (two years). The …


Western Rock Lobster Fishery Harvest Strategy And Decision Rules Framework Proposals. A Discussion Paper., Department Of Fisheries Western Australia Mar 2010

Western Rock Lobster Fishery Harvest Strategy And Decision Rules Framework Proposals. A Discussion Paper., Department Of Fisheries Western Australia

Fisheries Management Papers

This paper outlines proposals designed to be used in an updated and improved Harvest Strategy and Decision Rules Framework (referred to as the ‘Decision Rules’) that has been developed to meet the short and long term sustainability and economic needs of the West Coast Rock Lobster Managed Fishery. This approach represents international ‘best practice’ for fisheries management and is consistent with the Commonwealth Government’s Fisheries Harvest Strategy Policy1 .


A Model-Based Approach For Making Ecological Inference From Distance Sampling Data, Devin S. Johnson, Jeffrey L. Laake, Jay M. Ver Hoef Mar 2010

A Model-Based Approach For Making Ecological Inference From Distance Sampling Data, Devin S. Johnson, Jeffrey L. Laake, Jay M. Ver Hoef

United States Department of Commerce: Staff Publications

We consider a fully model-based approach for the analysis of distance sampling data. Distance sampling has been widely used to estimate abundance (or density) of animals or plants in a spatially explicit study area. There is, however, no readily available method of making statistical inference on the relationships between abundance and environmental covariates. Spatial Poisson process likelihoods can be used to simultaneously estimate detection and intensity parameters by modeling distance sampling data as a thinned spatial point process. A model-based spatial approach to distance sampling data has three main benefits: it allows complex and opportunistic transect designs to be employed, …


Double-Observer Line Transect Methods: Levels Of Independence, Stephen T. Buckland, Jeffrey L. Laake, David L. Borchers Mar 2010

Double-Observer Line Transect Methods: Levels Of Independence, Stephen T. Buckland, Jeffrey L. Laake, David L. Borchers

United States Department of Commerce: Staff Publications

Double-observer line transect methods are becoming increasingly widespread, especially for the estimation of marine mammal abundance from aerial and shipboard surveys when detection of animals on the line is uncertain. The resulting data supplement conventional distance sampling data with two-sample mark–recapture data. Like conventional mark–recapture data, these have inherent problems for estimating abundance in the presence of heterogeneity. Unlike conventional mark–recapture methods, line transect methods use knowledge of the distribution of a covariate, which affects detection probability (namely, distance from the transect line) in inference. This knowledge can be used to diagnose unmodeled heterogeneity in the mark–recapture component of the …


Kentucky River Watershed Watch: A Summary Of Volunteer Water Quality Sampling Efforts In The Kentucky River Basin From 1999 To 2009, Malissa Mcalister, Madhu Akasapu, Ben Albritton, Lindell Ormsbee, Dan Carey Mar 2010

Kentucky River Watershed Watch: A Summary Of Volunteer Water Quality Sampling Efforts In The Kentucky River Basin From 1999 To 2009, Malissa Mcalister, Madhu Akasapu, Ben Albritton, Lindell Ormsbee, Dan Carey

Kentucky River Watershed Watch

No abstract provided.


Northern Great Plains Network Vital Signs Monitoring Plan, Robert A. Gitzen, Marcia Wilson, United States National Park Service, Northern Great Plains Inventory And Monitoring Network, Mike Bynum, John Wrede, Joshua J. Millspaugh, Kara J. Paintner Mar 2010

Northern Great Plains Network Vital Signs Monitoring Plan, Robert A. Gitzen, Marcia Wilson, United States National Park Service, Northern Great Plains Inventory And Monitoring Network, Mike Bynum, John Wrede, Joshua J. Millspaugh, Kara J. Paintner

United States National Park Service: Publications

Executive Summary

The condition of natural resources in parks and other units of the National Park Service (NPS) is fundamental to this agency’s mission to manage park resources “unimpaired for the enjoyment of future generations.” Park managers are increasingly confronted with complex and challenging resource management issues and need a broad-based understanding of the status and trends of park resources for the long-term protection of park ecosystems. The National Park Service has initiated a long-term ecological “Vital Signs” monitoring program to provide the minimum infrastructure needed to track the overall condition of natural resources in parks and to provide early …


Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Final Project Report, Scott R. Abella, Margaret N. Rees Mar 2010

Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Final Project Report, Scott R. Abella, Margaret N. Rees

Vegetation Monitoring

Vegetation Monitoring and Analysis at Lake Mead National Recreation Area (NRA) was funded by the Multi-Species Habitat Conservation Plan, Southern Nevada Public Land Management Act, Lower Colorado River Multi-Species Conservation Program, and Lake Mead NRA base-funds. This Cooperative Task Agreement was awarded to the Public Lands Institute (PLI) at the University of Nevada, Las Vegas (UNLV) on September 30, 2006 with the term ending December 31, 2009, as modified. The primary purpose of this Task Agreement was to work within an interagency framework towards the accomplishment of three main vegetation management objectives. These three goals were to: (1) inventory, research …


Conserving Migratory Land Birds In The New World: Do We Know Enough?, John Faaborg, Richard T. Holmes, Angela D. Anders, Keith L. Bildstein Mar 2010

Conserving Migratory Land Birds In The New World: Do We Know Enough?, John Faaborg, Richard T. Holmes, Angela D. Anders, Keith L. Bildstein

Dartmouth Scholarship

Migratory bird needs must be met during four phases of the year: breeding season, fall migration, wintering, and spring migration; thus, management may be needed during all four phases. The bulk of research and management has focused on the breeding season, although several issues remain unsettled, including the spatial extent of habitat influences on fitness and the importance of habitat on the breeding grounds used after breeding. Although detailed investigations have shed light on the ecology and population dynamics of a few avian species, knowledge is sketchy for most species. Replication of comprehensive studies is needed for multiple species across …


Forest Restoration In A Mixed-Ownership Landscape Under Climate Change, Catherine Ravenscroft, Robert M. Scheller, David J. Mladenoff, Mark A. White Mar 2010

Forest Restoration In A Mixed-Ownership Landscape Under Climate Change, Catherine Ravenscroft, Robert M. Scheller, David J. Mladenoff, Mark A. White

Environmental Science and Management Faculty Publications and Presentations

The article presents a study regarding forest management associated with climate change. It mentions that preservation endeavors and restoration schemes should diminish current threats like unsuited forest management and development while integrating possible effects of climate change. It also stresses that an adaptive approach to management can be the most efficient strategy of forest restoration given the doubts of climate change impacts.


Disturbance And Plant Succession In The Mojave And Sonoran Deserts Of The American Southwest, Scott R. Abella Mar 2010

Disturbance And Plant Succession In The Mojave And Sonoran Deserts Of The American Southwest, Scott R. Abella

Public Policy and Leadership Faculty Research

Disturbances such as fire, land clearing, and road building remove vegetation and can have major influences on public health through effects on air quality, aesthetics, recreational opportunities, natural resource availability, and economics. Plant recovery and succession following disturbance are poorly understood in arid lands relative to more temperate regions. This study quantitatively reviewed vegetation reestablishment following a variety of disturbances in the Mojave and Sonoran Deserts of southwestern North America. A total of 47 studies met inclusion criteria for the review. The time estimated by 29 individual studies for full reestablishment of total perennial plant cover was 76 years. Although …


Siltcoos Lake Nonpoint Source Implementation Grant: Water Quality Conditions And Nutrient Sources, Mark D. Sytsma, Rich Miller Mar 2010

Siltcoos Lake Nonpoint Source Implementation Grant: Water Quality Conditions And Nutrient Sources, Mark D. Sytsma, Rich Miller

Center for Lakes and Reservoirs Publications and Presentations

Siltcoos Lake is a large (1280 hectares), shallow (mean depth 3.3 m; maximum depth 6.7 m) lake located on the Central Oregon Coast, just south of Florence and bordered by Dunes City, Oregon. The outflow and water level of Siltcoos Lake is regulated by a dam on the Siltcoos River 4 km upstream from the Pacific. Several permanent streams feed the lake from its 176 square kilometer watershed including Fiddle Creek, Maple Creek, and Woahink Creek, the outflow from Woahink Lake. Much of the watershed is forested and used for timber harvest, residential development, and limited agricultural production.

The lake …


Interview With Jacquin Dole, Riverside Farms, 2010 (Audio), Jacquin Dole Feb 2010

Interview With Jacquin Dole, Riverside Farms, 2010 (Audio), Jacquin Dole

All Sustainability History Project Oral Histories

Interview of Jacquin Dole by Paul Hopper at Riverside Farm McMinnville, Oregon on February 28th, 2010.

The interview index is available for download.


Interview With Katy Kolker, Portland Fruit Tree Project, 2010 (Audio), Katy Kolker Feb 2010

Interview With Katy Kolker, Portland Fruit Tree Project, 2010 (Audio), Katy Kolker

All Sustainability History Project Oral Histories

Interview of Katy Kolker by Dan Stillinger in Portland, Oregon on February 27th, 2010.

The interview index is available for download.


Select Tissue Mineralconcentrations And Chronic Wasting Disease Status In Mule Deer From North-Central Colorado, Lisa L. Wolfe, Mary M. Conner, Cathy L. Bedwell, Paul M. Lukacs, Michael W. Miller Feb 2010

Select Tissue Mineralconcentrations And Chronic Wasting Disease Status In Mule Deer From North-Central Colorado, Lisa L. Wolfe, Mary M. Conner, Cathy L. Bedwell, Paul M. Lukacs, Michael W. Miller

Wildland Resources Faculty Publications

Trace mineral imbalances have been suggested as having a causative or contributory role in chronic wasting disease (CWD), a prion disease of several North American cervid species. To begin exploring relationships between tissue mineral concentrations and CWD in natural systems, we measured liver tissue concentrations of copper, manganese, and molybdenum in samples from 447 apparently healthy, adult (≥2 yr old) mule deer (Odocoileus hemionus) culled or vehicle killed from free-ranging populations in north-central Colorado, United States, where CWD occurs naturally; we also measured copper concentrations in brain-stem (medulla oblongata at the obex) tissue from 181 of these deer. Analyses revealed …


Long-Term And Seasonal Trends In Phytoplankton Production And Biomass In Tampa Bay, Florida., J.O. R. Johansson Feb 2010

Long-Term And Seasonal Trends In Phytoplankton Production And Biomass In Tampa Bay, Florida., J.O. R. Johansson

Reports

Phytoplankton production is a basic process in aquatic ecosystems that converts inorganic carbon into organic matter and provides an important indicator of trophic state. The City of Tampa Bay Study Group maintains a 32 year long monthly record of phytoplankton production rates and biomass (chlorophyll-a) in Hillsborough Bay (HB) and Middle Tampa Bay (MTB), and a recent record during the last nine years for Old Tampa Bay (OTB). Production is measured using the classic in situ 14C method with samples incubated vertically in the water column. Annual production rates during the most recent decade are about 410gCm-2 for HB, 350gCm-2 …


Algal Biofuel, Feb 5, 2010, Harry Reid Center, University Of Nevada, Las Vegas Feb 2010

Algal Biofuel, Feb 5, 2010, Harry Reid Center, University Of Nevada, Las Vegas

Biofuels

News in Brief

1. UVa engineers find significant environmental impacts with algae-based biofuel (Jan-21, 2010)

2. IPCC scientist: Global cooling headed our way for the next 30 years? (Jan 11, 2010)

3. Shining a Light on Plants' Quantum Secret to Boost Photosynthesis (Feb 3, 2010)


Water Source Partitioning For Shrubland Transpiration Using Innovative Field Methods, Dale A. Devitt, Michael Young, Matthew S. Lachniet, Jeremy Koonce, Amanda Wagner, Brian M. Bird, J. Healey Feb 2010

Water Source Partitioning For Shrubland Transpiration Using Innovative Field Methods, Dale A. Devitt, Michael Young, Matthew S. Lachniet, Jeremy Koonce, Amanda Wagner, Brian M. Bird, J. Healey

2010 Annual Nevada NSF EPSCoR Climate Change Conference

37 PowerPoint slides Convener: Franco Biondi, UNR & Michael Young, DRI Session 4: Ecological Change and Water Resources Abstract: -Climate change models predict a decline in precipitation over the next few decades throughout much of the southwest. -Such change has the potential to shift water uptake dynamics of phreatophytes -If groundwater pumping also occurs, the impact of climate change could be exacerbated. -A better understanding of the forces that drive the coupling and decoupling of phreatophytes to groundwater is needed.