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Full-Text Articles in Physical Sciences and Mathematics

Unintended Consequences: Potential Downsides Of The Air Force's Conversion To Biofuels, Mark N. Goltz, Charles A. Bleckmann, Charles M. Mackay, Khai Vuong, Jerrod P. Mccomb Jul 2011

Unintended Consequences: Potential Downsides Of The Air Force's Conversion To Biofuels, Mark N. Goltz, Charles A. Bleckmann, Charles M. Mackay, Khai Vuong, Jerrod P. Mccomb

Faculty Publications

The desire to reduce US dependence on foreign energy, ongoing environmental concerns, and the rising cost of petroleum have sparked significant development of greener alternative and renewable energy sources such as alcohol-based biofuels. To address these issues, the Department of Defense DOD has moved to diminish its reliance on petroleum for fueling aircraft and ground equipment. The US Air Force, in alignment with DOD objectives, has initiated several goals for reducing its use of energy: (1) decrease the use of petroleum-based fuel by 2 percent annually for the vehicle fleet, (2) increase the use of alternative fuel in motor vehicles …


Making Connections Between Science And Equity: A Motivation To Teach Science In Elementary Grades, Grinell Smith, Colette Rabin Apr 2011

Making Connections Between Science And Equity: A Motivation To Teach Science In Elementary Grades, Grinell Smith, Colette Rabin

Faculty Publications

Teacher quality is among the strongest correlates of student outcomes. However, only about a quarter of the nation’s elementary teachers consider themselves qualified to teach science. In this descriptive and exploratory study, we investigated whether helping pre-service teacher candidates explore connections between science and issues of equity, particularly around sustainability issues, could help them see the importance of teaching science to their students more often. Qualitative and quantitative data were collected from 59 students enrolled in revised science methods courses at a large public university. Our findings suggest that positioning science instruction thusly was perceived as a strong motivator to …


The Changing Roles Of Natural Resource Professionals: Providing Tools To Students To Teach The Public About Fire, Pat Stephens Williams, Brian Oswald, Karen Stafford, Justice Jones, David Kulhavy Jan 2011

The Changing Roles Of Natural Resource Professionals: Providing Tools To Students To Teach The Public About Fire, Pat Stephens Williams, Brian Oswald, Karen Stafford, Justice Jones, David Kulhavy

Faculty Publications

The Arthur Temple College of Forestry and Agriculture (ATCOFA) at Stephen F. Austin State University is taking a proactive stance toward preparing forestry students to work closely with the public on fire planning in wildland-urban interface areas. ATCOFA's incorporation of the "Changing Roles" curriculum provides lessons on how natural resource managers' roles are (1) different than they used to be, and (2) ever-evolving. The undergraduate Forestry Field Station summer program at the University's Piney Woods Conservation Center now emphasizes the importance and challenges of working with the public. The program brings practicing professionals from the Texas Forest Service to describe …


Legal Initiatives Driving Clean Up Of Chesapeake Bay, Roy A. Hoagland, Jon Mueller Jan 2011

Legal Initiatives Driving Clean Up Of Chesapeake Bay, Roy A. Hoagland, Jon Mueller

Faculty Publications

No abstract provided.


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 …


Broad-Scale Relations Between Conservation Reserve Program And Grassland Birds: Do Cover Type, Configuration And Contract Age Matter?, Sam Riffell, Daniel Scognamillo, L. Wes Burger Jr., Shawn Bucholtz Jan 2010

Broad-Scale Relations Between Conservation Reserve Program And Grassland Birds: Do Cover Type, Configuration And Contract Age Matter?, Sam Riffell, Daniel Scognamillo, L. Wes Burger Jr., Shawn Bucholtz

Faculty Publications

The Conservation Reserve Program (CRP) is a voluntary cropland set-aside program where environmentally-sensitive cropland is retired to a conservation practice. Grassland birds should benefit because most CRP is grass habitat and because amount of land in CRP is highest in agriculture-dominated areas of the United States where grassland habitat has been most impacted. We used the Breeding Bird Survey and Common Land Unit (CLU) data (spatially-explicit data of farm field boundaries and land cover) to identify relations between types and configurations of CRP and grassland bird abundance in 3 Midwestern states. All 13 species we studied were related to at …


Song Of Wekiva: Florida’S Wild River And Its Democratic Vista, Steve Phelan Jan 2010

Song Of Wekiva: Florida’S Wild River And Its Democratic Vista, Steve Phelan

Faculty Publications

Today hundreds of thousands enjoy the river every year. We are a different breed. When I take our children or my students to the river or walk along its sandy uplands to show them undiscovered and unmapped springs popping out of the ground, they and I are still abiding in a domesticated world that erects a substantial, almost impervious barrier to the wilderness of the river. Nevertheless, that wildness is built unconsciously into our bodies. We are not like the Timucuans, the first humans to come down the St. Johns River and eventually up the Wekiva to the two main …


Association Between Fire Return Interval And Population Dynamics In Four California Populations Of Tecate Cypress (Cupressus Forbesii), Roland C. De Gouvenain, Ali M. Ansary Dec 2006

Association Between Fire Return Interval And Population Dynamics In Four California Populations Of Tecate Cypress (Cupressus Forbesii), Roland C. De Gouvenain, Ali M. Ansary

Faculty Publications

The Tecate cypress (Cupressus forbesii) is a tree species associated with chaparral ecosystems in southern California and northern Baja California, Mexico. It is fire-adapted, its regeneration triggered by the opening of serotinous cones when adult trees are burned. Surveys made in the 1980s by others suggested that some Tecate cypress populations were declining, and some authors suggested that increased fire frequency in southern California was a major factor for this decline. We asked whether current population trends were still negative for Tecate cypress 20 years later, and whether population growth was associated with fire return interval length. Based on demographic, …


Impacts Of A Manure Composting Program On Stream Water Quality, A. Bekele, A. M.S. Mcfarland, A. J. Whisenant Jan 2006

Impacts Of A Manure Composting Program On Stream Water Quality, A. Bekele, A. M.S. Mcfarland, A. J. Whisenant

Faculty Publications

In February 2001, the Texas Commission on Environmental Quality (TCEQ) adopted a Total Maximum Daily Load (TMDL) for soluble reactive phosphorus (SRP) along the North Bosque River. Within this TMDL, dairy waste application fields were identified as the major nonpoint-source contribution of nutrients. In September 2000, a manure composting program was initiated that resulted in about 500,000 metric tons of dairy manure being hauled to composting facilities and exported from the watershed through December 2004. To evaluate the impact of the manure composting program on stream water quality, storm event mean concentrations of nutrients and total suspended solids were compared …


New Orleans, The Chesapeake, And The Future Of Environmental Assessment: Overcoming The Natural Resources Law Of Unintended Consequences, Erin Ryan Jan 2006

New Orleans, The Chesapeake, And The Future Of Environmental Assessment: Overcoming The Natural Resources Law Of Unintended Consequences, Erin Ryan

Faculty Publications

No abstract provided.


Runoff And Sediment Losses From Annual And Unusual Storm Events From The Alto Experimental Watersheds, Texas: 23 Years After Silvicultural Treatments, Matthew W. Mcbroom, R Scott Beasley, Mingteh Chang, Brian Gowin, George G. Ice Oct 2003

Runoff And Sediment Losses From Annual And Unusual Storm Events From The Alto Experimental Watersheds, Texas: 23 Years After Silvicultural Treatments, Matthew W. Mcbroom, R Scott Beasley, Mingteh Chang, Brian Gowin, George G. Ice

Faculty Publications

Evaluating the potential impacts of intensive silvicultural practices on water quality is critical for establishing the long-term sustainability of contemporary forest management practices. From 1979 to 1985, a study involving nine small (~2.5 ha) forested watersheds was conducted near Alto, Texas in the upper western Gulf-Coastal Plain to evaluate the impacts then-current silvicultural practices on water quality. In the years following the study, silvicultural Best Management Practices (BMPs) including Streamside Management Zones (SMZs) and other erosion control practices evolved and questions arose about the applicability of earlier results to current practices. In 1999, these same watersheds were reinstrumented to evaluate …


Bacteriological Water Quality Of Forested And Pastured Streams Receiving Land-Applied Poultry Litter, Matthew W. Mcbroom, Chang Mingteh, Charles Wells May 2003

Bacteriological Water Quality Of Forested And Pastured Streams Receiving Land-Applied Poultry Litter, Matthew W. Mcbroom, Chang Mingteh, Charles Wells

Faculty Publications

Poultry production is a growing industry in East Texas, generating about 360,000 m tons of broiler litter each year as a by-product for application on pasturelands. Grab samples of fecal coliform (FC) and fecal streptococcus (FS) were collected monthly between March and December 1996 and FC and E-coli samples were collected weekly between July and October 2001 at six sites on the Waffelo and Terrapin Creeks in Nacogdoches County, Texas to assess possible impacts of poultry litter application on bacterial water quality. Sites were grouped by three pairs with each pair consisting of one upstream site in predominantly forested area …


Mercury Concentrations In Streams Of East Texas, Mingteh Chang, Mark C. Cochran, R. Scott Beasley, Matthew W. Mcbroom May 2003

Mercury Concentrations In Streams Of East Texas, Mingteh Chang, Mark C. Cochran, R. Scott Beasley, Matthew W. Mcbroom

Faculty Publications

Recent studies on potential mercury (Hg) contamination of fish from East Texas lakes and waterways have caused concern about mercury levels in East Texas waters. Historical records of Hg concentrations in 33 East Texas streams showed that median concentrations for each stream segment were no different than other U.S. streams. All the means and medians for stream segments having at least 20 recorded measurements were less than Texas (2.4 µg/L) water quality standards. Water samples collected in December 1995 and March 1996 from 6 different stream sites in Nacogdoches County had concentrations similar to historical records. Due to biological magnification, …


Soil Leachate Responses During 10 Years Of Induced Whole-Watershed Acidification, Pamela J. Edwards, James N. Kochenderfer, Dean W. Coble, Mary Beth Adams Jan 2002

Soil Leachate Responses During 10 Years Of Induced Whole-Watershed Acidification, Pamela J. Edwards, James N. Kochenderfer, Dean W. Coble, Mary Beth Adams

Faculty Publications

Soil solution was collected from zero-tension lysimeters for 10 yr on two small central Appalachian watersheds in West Virginia, U.S.A. Ammonium sulfate fertilizer was applied to one catchment 3 times per year during each year. The other watershed was used as a reference to account for ambient baseline conditions. Ca and Mg concentrations collected below the A- and B-horizons of the treated watershed increased and then decreased over time as a result of the treatment. By contrast, Ca and Mg concentrations in the C-horizon continued to increase throughout the study period.


Book Review Of Eco-Pragmatism: Making Sensible Environmental Decisions In An Uncertain World, Lynda L. Butler Jan 2001

Book Review Of Eco-Pragmatism: Making Sensible Environmental Decisions In An Uncertain World, Lynda L. Butler

Faculty Publications

No abstract provided.


Coastal Marine Science For Law And Business Students: Preparing Law And Business Professionals To Make "Informed Decisions" About Coastal Issues, David H. Niebuhr, Lynda L. Butler, Don Rahtz, Britt E. Anderson, April N. Lawrence Jan 1998

Coastal Marine Science For Law And Business Students: Preparing Law And Business Professionals To Make "Informed Decisions" About Coastal Issues, David H. Niebuhr, Lynda L. Butler, Don Rahtz, Britt E. Anderson, April N. Lawrence

Faculty Publications

The rigors of employment-directed undergraduate education. and decreased emphasis on "Liberal Arts" studies occurring at some colleges and universities has left many graduates with a level of scientific understanding which is inadequate to make infonned choices about issues which effect the environment. To address this lack of scientific understanding. the Chesapeake Bay National Estuarine Research Reserve (Virginia) and the Virginia Institute of Marine Science, with the Marshall-Wythe School of Law and the School of Business Administration of the College of William and Mary are developing a Coastal Ecosystem Science Program to teach future law and business professionals the basics of …


Federal Minimums: Insufficient To Save The Bay, Roy A. Hoagland, Jean G. Watts May 1995

Federal Minimums: Insufficient To Save The Bay, Roy A. Hoagland, Jean G. Watts

Faculty Publications

No abstract provided.


Comparison Of Dietary Overlap Between Allopatric And Sympatric Geckos, Paul D. Klawinski, R. Kathryn Vaughan, Daniel Saenz, William Godwin Jan 1994

Comparison Of Dietary Overlap Between Allopatric And Sympatric Geckos, Paul D. Klawinski, R. Kathryn Vaughan, Daniel Saenz, William Godwin

Faculty Publications

Two gecko species, Hemidactylus turcicus and Cyrtopodion scabrum, have been introduced into the Port of Galveston, Texas. While H. turcicus has been established for a longer period of time, the relatively recent introduction of C. scabrum near the entrance of the Port has apparently led to the displacement of H. turcicus in that area. This has resulted in a distribution in which the two populations’ are largely allopatric except for a narrow band of sympatry at the periphery of each of their ranges. We examined stomach contents of both species in allopatry and sympatry in order to determine if …


Federal Protection Of Unique Environmental Interests: Endangered And Threatened Species, Ronald H. Rosenberg Jan 1980

Federal Protection Of Unique Environmental Interests: Endangered And Threatened Species, Ronald H. Rosenberg

Faculty Publications

Endangered species protection has long been favored by many Americans, who watched regretfully as the numbers of American eagles, buffaloes and other species dwindled toward extinction. Only recently, however, has species protection become a matter of public controversy, subsumed in the more general "development v. environment" debate. In this Article, Professor Rosenberg surveys the federal government's role in species protection, with a special focus on the Endangered Species Act of 1973. Prompted by the much-publicized Supreme Court decision in the "snail darter case"--TVA v. Hill-Congress extensively amended the Act in 1978. After a detailed analysis of these amendments, Professor Rosenberg …