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Commonwealth Times 2013-10-07 Oct 2013

Commonwealth Times 2013-10-07

Commonwealth Times, 1969-

No abstract provided.

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Physiological Mechanisms Of Shrub Encroachment: Linking Enhanced Hydraulic Capacity To Efficient Light Capture And Processing, Sheri Shiflett Jul 2013

Physiological Mechanisms Of Shrub Encroachment: Linking Enhanced Hydraulic Capacity To Efficient Light Capture And Processing, Sheri Shiflett

Theses and Dissertations

Woody plant expansion has been documented for decades in many different ecosystems, often due to anthropogenic disturbances to the environment and yielding vast changes in ecosystem functioning. While causes and consequences of woody expansion have been well documented, few studies have investigated functional traits of woody species that promote rapid expansion in range. My objective was to determine if hydraulic efficiency confers enhanced photosynthetic efficiency so that functional traits representing light and water use may be possible mechanisms facilitating woody encroachment into grasslands and forest understories. I quantified leaf-level light environment, photosynthetic activity, and hydraulic characteristics of three sympatric broadleaf …

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Reproduction And Functional Response Of Cornus Florida Across An Urban Landscape Gradient, Angela Redwine May 2013

Reproduction And Functional Response Of Cornus Florida Across An Urban Landscape Gradient, Angela Redwine

Theses and Dissertations

Urbanization greatly alters plant and pollinator communities and can affect pollinator movement and subsequent gene flow. Plants persisting in urban areas must adjust to local environmental conditions often different from those in which they naturally evolved, and cultivation techniques for landscaping species have developed traits suitable for existence in urban habitats. Cultivated varieties and native conspecifics often exist in geographic proximity, and if pollinator movement is not blocked by urban structural components, functional differences may negatively impact spatially proximate native populations. I used spatial analysis of successful pollination of Cornus florida to estimate how pollinator movement is affected by urban …

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Reforestation Of Red Spruce (Picea Rubens) On The Cheat Mountain Range, West Virginia, Justin Madron Apr 2013

Reforestation Of Red Spruce (Picea Rubens) On The Cheat Mountain Range, West Virginia, Justin Madron

Theses and Dissertations

The (Plethodon nettingi) Cheat Mountain Salamander is a rare and endangered species that relies heavily on (Picea rubens) Red Spruce for habitat. P. rubens communities on the Cheat Mountain range in West Virginia have been disturbed by fires and logging, and regeneration of P. rubens stands are central to the survival of the P. netting. A supervised and unsupervised landscape classification of three Landsat images over the past 26 years was conducted to analyze change in P. rubens communities on Cheat Mountain Range. Change detection results revealed that from 1986-2012 a 52% growth increase of P. rubens stands, 18% loss, …

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Commonwealth Times 2013-01-24 Jan 2013

Commonwealth Times 2013-01-24

Commonwealth Times, 1969-

No abstract provided.

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Virginia Commonwealth University Fall Commencement Program [Corrected Copy] [2013], Virginia Commonwealth University Jan 2013

Virginia Commonwealth University Fall Commencement Program [Corrected Copy] [2013], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

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Virginia Commonwealth University Fall Commencement Program [2013], Virginia Commonwealth University Jan 2013

Virginia Commonwealth University Fall Commencement Program [2013], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

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Virginia Commonwealth University Graduate And Professional Programs Bulletin [2013], Virginia Commonwealth University Jan 2013

Virginia Commonwealth University Graduate And Professional Programs Bulletin [2013], Virginia Commonwealth University

VCU Bulletins

Graduate and professional programs bulletin for Virginia Commonwealth University for the academic year 2013-2014. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for graduate programs.

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A Macrophysiological Analysis Of Energetic Constraints On Geographic Range Size In Mammals, Salvatore J. Agosta, Joseph Bernado, Gerardo Ceballos, Michael A. Steele Jan 2013

A Macrophysiological Analysis Of Energetic Constraints On Geographic Range Size In Mammals, Salvatore J. Agosta, Joseph Bernado, Gerardo Ceballos, Michael A. Steele

Biology Publications

Physiological processes are essential for understanding the distribution and abundance of organisms, and recently, with widespread attention to climate change, physiology has been ushered back to the forefront of ecological thinking. We present a macrophysiological analysis of the energetics of geographic range size using combined data on body size, basal metabolic rate (BMR), phylogeny and range properties for 574 species of mammals. We propose three mechanisms by which interspecific variation in BMR should relate positively to geographic range size: (i) Thermal Plasticity Hypothesis, (ii) Activity Levels/Dispersal Hypothesis, and (iii) Energy Constraint Hypothesis. Although each mechanism predicts a positive correlation between …

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Virginia Commonwealth University Commencement Program [2013], Virginia Commonwealth University Jan 2013

Virginia Commonwealth University Commencement Program [2013], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

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Examining The Relationship Between Particulate Matter, Nitrogen Oxide, Carbon Oxides, Sulfur Dioxide And Hypertension In Urban Areas In India: A Review, Hiren Kolli Jan 2013

Examining The Relationship Between Particulate Matter, Nitrogen Oxide, Carbon Oxides, Sulfur Dioxide And Hypertension In Urban Areas In India: A Review, Hiren Kolli

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

While blood pressure may be decreasing around the world, it has been on the rise in India (Kounteya, 2012). According to the World Health Organization, the average blood pressure went down by 2.7mm Hg among women globally, while increasing by 2.4mm Hg in India. In men, blood pressure decreased by 2.3mm Hg globally in the past three decades but increased by 2.2mm Hg in India (Kounteya, 2012). Almost three-quarters of people with hypertension live in developing countries with limited health resources where there is very low awareness of hypertension, and India is one of these countries. Hypertension is the leading …

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The Atlantic Bluefin Tuna: A Public Policy Approach To Saving An Iconic Species, Timothy Patrick O'Brien Dec 2012

The Atlantic Bluefin Tuna: A Public Policy Approach To Saving An Iconic Species, Timothy Patrick O'Brien

Theses and Dissertations

The Atlantic Bluefin Tuna (Thunnus thynnus) is perhaps the most magnificent and most marvelous nomadic wild animal living in the world. It lives in the deep blue waters of the Atlantic Ocean and is one of the largest of the world’s fin fish and the largest of the 48 other species of tuna (Kuhn, 1996). It is a species that seems to have been designed and sculpted by an artist—sleek, smooth, and beautiful—instead of having been a product of an evolutionary process. Today, the existence and future of the Atlantic Bluefin Tuna is in question because of the constant overexploitation …

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Life History Analysis Of James River Atlantic Sturgeon (Acipenser Oxyrinchus Oxyrinchus) With Implications For Management And Recovery Of The Species, Matthew Balazik Dec 2012

Life History Analysis Of James River Atlantic Sturgeon (Acipenser Oxyrinchus Oxyrinchus) With Implications For Management And Recovery Of The Species, Matthew Balazik

Theses and Dissertations

Sturgeon species (family Acipenseridae) are threatened globally due to habitat destruction, pollution, and overfishing. The Atlantic sturgeon Acipenser oxyrinchus oxyrinchus was listed as a federally endangered species in 2012. Atlantic sturgeon have a complex life history that utilizes a wide range of habitats. Timing of life history varies in different areas requiring each population to be studied. Very little work has been published on Atlantic sturgeon reproduction in the James River, Virginia. To aid the recovery of James River Atlantic sturgeon, aspects of life history need to be addressed. To increase understanding of Atlantic sturgeon life history a length at …

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The Effects Of River Sediment, Endosulfan, And Moderate Hypoxia On Blue Crabs (Callinectes Sapidus) From The Tidal, Freshwater James River, Laura Williams Nov 2012

The Effects Of River Sediment, Endosulfan, And Moderate Hypoxia On Blue Crabs (Callinectes Sapidus) From The Tidal, Freshwater James River, Laura Williams

Theses and Dissertations

Juvenile male blue crabs move into the tidal, freshwater James River during warmer months to feed and grow by undergoing molting. In crustaceans, growth and molting are hormonally controlled. The physiological effects of a multiple-stressor environment are determined by comparing the blue crab’s oxygen uptake after exposure to pure sand, James River sediment, or endosulfan-spiked sand. The effect of multiple stressors on molting is measured by the activity level of N-acetyl-ß-glucosaminidase (NAG), an enzyme in epidermal tissue important to molting. The oxygen uptake was decreased by exposure to James River sediment but not for exposure to endosulfan for seven days. …

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Commonwealth Times 2012-11-01 Nov 2012

Commonwealth Times 2012-11-01

Commonwealth Times, 1969-

No abstract provided.

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Using Macroinvertebrate Community Composition To Distinguish Between Natural And Anthropogenic Sedimentation, Amanda E. Schutt Sep 2012

Using Macroinvertebrate Community Composition To Distinguish Between Natural And Anthropogenic Sedimentation, Amanda E. Schutt

Theses and Dissertations

Excess fine sediment from human activity is a major pollutant to streams across the U.S.; however, distinguishing human-induced sedimentation from natural fine sediment is complex. The U.S. Environmental Protection Agency recently implemented a protocol for the quantitative field assessment of human-induced sedimentation using measurements of stream geomorphology. Macroinvertebrate community composition, streambed sediment stability, and sediment composition were studied at 49 sites in the James River watershed in central Virginia. Sediment composition was found to be a stronger driver of community composition than sediment stability. Although I was not able to show that macroinvertebrate metrics were related to sediment stability independently …

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Characterization Of Microsatellite Loci And Pilot Population Genetic Analysis In Hickory Shad, Alosa Mediocris, Fnu Vishakha Aug 2012

Characterization Of Microsatellite Loci And Pilot Population Genetic Analysis In Hickory Shad, Alosa Mediocris, Fnu Vishakha

Theses and Dissertations

The hickory shad (Alosa mediocris) is a relatively understudied species of the anadromous fish sub-family Alosinae. This study, the first population genetic analysis of this species, employed 12 neutral microsatellite loci to estimate genetic diversity and population structure in tributaries of lower Chesapeake Bay, Virginia including James River and its tributaries (Appomattox and Chickahominy Rivers), Rappahannock River, and Pamunkey River. Genetic variation was extremely low. Estimates of observed heterozygosity were lower than expected heterozygosity. Significant population structure was detected among the six samples (FST = 0.093, p = 0.01). Effective population sizes were low (Ne ranged from 2 to 134). …

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A Water Quality Investigation Of Kimages Creek, Michael Trop Aug 2012

A Water Quality Investigation Of Kimages Creek, Michael Trop

Theses and Dissertations

Analysis of continuous monitoring water quality data (temperature, specific conductivity, depth, pH, dissolved oxygen, and turbidity) at two locations in a tidal freshwater creek (Kimages Creek) characterized seasonal variation and responses to short-term events. Supplemental water quality measurements were collected to describe longitudinal variations in the creek. There were significant differences in water quality between the two continuous monitoring stations (one tidal and unforested, the other non-tidal and forested) over varying time scales. Rain events showed increases in turbidity, depth and dissolved oxygen, and reductions in temperature, conductivity, and pH at both stations. Tides influenced the water quality at the …

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Essential Spawning Habitat For Atlantic Sturgeon In The James River, Virginia., Geoffrey Austin Aug 2012

Essential Spawning Habitat For Atlantic Sturgeon In The James River, Virginia., Geoffrey Austin

Theses and Dissertations

Substrate composition plays a critical role in determining the spawning success of Atlantic sturgeon. A benthic analysis of the tidal freshwater portion of the James River, Virginia, was performed to locate and protect remaining sturgeon spawning habitat within the James River system. I modeled structural habitat, substrate distribution, and river bathymetry from Richmond, Virginia to the Appomattox River confluence. A classification model was developed to describe the dominant substrate type (mud/silt, sand, gravel, bedrock) using side scan sonar data collected from August 2011-Febuary 2012. River depth, bottom imagery, substrate density (hardness), and ground truth substrate samples were interpolated into a …

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Analysis Of The Fish Community On Tidal-Freshwater Constructed Reefs, Briana Langford Jul 2012

Analysis Of The Fish Community On Tidal-Freshwater Constructed Reefs, Briana Langford

Theses and Dissertations

Constructed reefs are used successfully in marine systems to enhance spawning habitat; this study examines the effectiveness of constructed reefs in a tidal-freshwater river. Fish abundance, species diversity and richness, residency, water column position, reproductive guilds, and feeding guilds were analyzed on two constructed reefs in the tidal-freshwater James River and compared to silted regions representing the primary substrate in the river. Reefs were sampled using hydroacoustics, electroshocking, gillnetting, trawling, and egg mats. The constructed reefs had a greater proportion of fish that broadcast spawn over hard substrate and a trend of more overall individual, residential, and demersal fish. The …

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Spatial Patterns Of Herbaceous And Woody Recruitment In A Recently Restored Mixed Tidal Regime Freshwater Wetland, James B. Deemy May 2012

Spatial Patterns Of Herbaceous And Woody Recruitment In A Recently Restored Mixed Tidal Regime Freshwater Wetland, James B. Deemy

Theses and Dissertations

Ecological restoration of a converted wetland was characterized within a recently drained impoundment along the James River in Charles City County, Virginia. Colonizing vegetation was assessed over three growing seasons in both tidal and non-tidal environments. Study objectives were to (1) examine geospatial relations of recruitment patterns among colonizing species over three growing seasons, (2) quantify species composition and potential differences between extant species cover and soil seed banks across restored and natural wetland habitats and (3) assess geospatial patterns to develop a GIS model of bald cypress (Taxodium distichum L.) recruitment. The two most common native colonizing species during …

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Sources And Fates Of Nutrients In The Tidal, Freshwater James River, William Isenberg Apr 2012

Sources And Fates Of Nutrients In The Tidal, Freshwater James River, William Isenberg

Theses and Dissertations

Tidal freshwater reaches of estuaries may play an important role in mitigating nutrient fluxes from watersheds to the coastal zone due to their location at the interface between riverine and estuarine systems. We developed annual N and P budgets for the tidal, freshwater James River over 4 calendar years (2007-2010) taking into account riverine inputs at the Fall Line, local points sources (including CSO events), ungagued inputs, riverine outputs, and tidal exchange. The tidal freshwater James River experiences high areal loading rates of TN (383 mg/m2/d) and TP (70 mg/m2/d) due to the combined effects of large watershed area and …

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Commonwealth Times 2012-04-12 Apr 2012

Commonwealth Times 2012-04-12

Commonwealth Times, 1969-

No abstract provided.

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Commonwealth Times 2012-02-09 Feb 2012

Commonwealth Times 2012-02-09

Commonwealth Times, 1969-

No abstract provided.

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Virginia Commonwealth University Fall Commencement Program [2012], Virginia Commonwealth University Jan 2012

Virginia Commonwealth University Fall Commencement Program [2012], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

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Virginia Commonwealth University Commencement Program [2012], Virginia Commonwealth University Jan 2012

Virginia Commonwealth University Commencement Program [2012], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

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Evaluation Of Brook Trout (Salvelinus Fontinalis) Introductions And Re-Introductions Into Four Virginia Blue Ridge Mountain Streams, Michael Isel Iii Dec 2011

Evaluation Of Brook Trout (Salvelinus Fontinalis) Introductions And Re-Introductions Into Four Virginia Blue Ridge Mountain Streams, Michael Isel Iii

Theses and Dissertations

Approximately 100 brook trout were transplanted into each of four Virginia streams in September 2008. Garth Run and Kinsey Run were re-introductions, and Wildcat Hollow and Sweet Run were new introductions. Single pass electrofishing (EF) surveys were conducted with a backpack electrofisher five times during the study. Selected trout > 70 mm but < 100 mm and all trout > 100 mm received a Biomark® 134.2 kHz passive integrated transponder (PIT) tag to identify individual fish upon recapture. Trout were present in all streams almost three years post introductions. Catches decreased across the first four surveys. Young of year catch rates severely decreased from June 2009 (n = …

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Commonwealth Times 2011-12-01 Dec 2011

Commonwealth Times 2011-12-01

Commonwealth Times, 1969-

No abstract provided.

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Commonwealth Times 2011-11-10 Nov 2011

Commonwealth Times 2011-11-10

Commonwealth Times, 1969-

No abstract provided.

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Composition Of Suspended And Benthic Particulate Matter In The Tidal Freshwater James River, Anne Schlegel Sep 2011

Composition Of Suspended And Benthic Particulate Matter In The Tidal Freshwater James River, Anne Schlegel

Theses and Dissertations

Investigating linkages between the compositions of suspended (seston) and benthic particulate matter is important to the understanding of organic matter (OM) cycling and nutrient retention in aquatic systems. We compared the quantity and quality of the truly suspended (TS) and settleable (SB) fractions of seston as well as benthic particulate matter in the tidal freshwater James River, Virginia. The mass of seston and OM was consistently higher in the TS fraction compared to the SB fraction. OM was preferentially retained in the TS fraction relative to seston. The proportional contribution of OM constituents (chlorophyll a, particulate organic carbon and nitrogen) …

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