Digital Commons Network^™

Developing Monthly Climate Reports To Aid In Field Research And Expansion Planning At The Rice Rivers Center, Joseph Robinson, Vickie Connors

Rice Rivers Center Research

No abstract provided.

Virginia Commonwealth University Commencement Program [2017], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

Virginia Commonwealth University Fall Commencement Program [2017], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

Virginia Commonwealth University Undergraduate Bulletin [2017], Virginia Commonwealth University

VCU Bulletins

Undergraduate bulletin for Virginia Commonwealth University for the academic year 2017-2018. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for undergraduate programs.

Improved Mixing System For Aquatic Mesocosm Facility, Kyle Boyce, Ben Chalfant, Ron Fitch

Capstone Design Expo Posters

The VCU Environmental Science Department had in its possession 24 500 gal tanks they had implemented to study the plankton and bacteria activity of the James River. Water was pumped up from the James River a quarter mile to the tanks and studied over week long periods to analyze the growth and survival of plankton and bacteria as it exists in the river. Over time it was found that the bacteria in the mesocosms would growth at an increased rate as sediments and inorganic matter fell out of suspensions. For this reason, it was necessary to develop an agitator that …

Virginia Commonwealth University Graduate Bulletin [2017], Virginia Commonwealth University

VCU Bulletins

Graduate bulletin for Virginia Commonwealth University for the academic year 2017-2018. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for graduate programs.

Virginia Commonwealth University Courses [2017], Virginia Commonwealth University

VCU Bulletins

Listing of courses for the 2017-2018 year.

Variation In Growth And Developmental Responses To Supraoptimal Temperatures Near Latitudinal Range Limits Of Gypsy Moth Lymantria Dispar (L.), An Expanding Invasive Species, Lily M. Thompson, Trevor M. Faske, Nana Banahene, Dominique Grim, Salvatore J. Agosta, Dylan Parry, Patrick C. Tobin, Derek M. Johnson, Kristine L. Grayson

Biology Publications

Variation in thermal performance within and between populations provides the potential for adaptive responses to increasing temperatures associated with climate change. Organisms experiencing temperatures above their optimum on a thermal performance curve exhibit rapid declines in function and these supraoptimal temperatures can be a critical physiological component of range limits. The gypsy moth, Lymantria dispar (L.) (Lepidoptera: Erebidae), is one of the best-documented biological invasions and factors driving its spatial spread are of significant ecological and economic interest. The present study examines gypsy moth sourced from different latitudes across its North American range for sensitivity to high temperature in constant …

Genetic Differentiation Of Spring-Spawning And Fall-Spawning Male Atlantic Sturgeon In The James River, Virginia, Matthew T. Balazik, Daniel J. Farrae, Tanya L. Darden, Greg C. Garman

Biology Publications

Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae) populations are currently at severely depleted levels due to historic overfishing, habitat loss, and pollution. The importance of biologically correct stock structure for effective conservation and management efforts is well known. Recent improvements in our understanding of Atlantic sturgeon migrations, movement, and the occurrence of putative dual spawning groups leads to questions regarding the true stock structure of this endangered species. In the James River, VA specifically, captures of spawning Atlantic sturgeon and accompanying telemetry data suggest there are two discrete spawning groups of Atlantic sturgeon. The two putative spawning groups were …

Biophysical Drivers Of Carbon Dioxide And Methane Fluxes In A Restored Tidal Freshwater Wetland, Ellen Stuart-Haëntjens, Scott C. Neubauer, William Shuart, Christopher M. Gough

Rice Rivers Center Research Symposium

Wetlands store large amounts of carbon (C) in biomass and soils, playing a crucial role in offsetting greenhouse gas (GHG) emissions; however, they also account for 30% of global yearly CH4 emissions. Anthropogenic disturbance has led to the decline of natural wetlands throughout the United States, with a corresponding increase in created and restored wetlands. Studies characterizing biogeochemical processes in restored forested wetlands, particularly those that are both tidal and freshwater, are lacking but essential for informing science- based carbon management.

Identifying Biotic Determinants Of Historic American Eel (Anguilla Rostrata) Distributions, Taylor E. Woods, Daniel J. Mcgarvey

Rice Rivers Center Research Symposium

Traditionally, ecologists studying large scale patterns in species distributions emphasize abiotic variables over biotic interactions. Noting that both abiotic & biotic variables likely determine distributions of all organisms, many ecologists now aim for a more comprehensive view of species distributions, inclusive of both abiotic and biotic components (Soberón 2007).

The Scope, The Scope

The Scope

Collection of all 2016 articles from The Scope.

About The Scope

This magazine was produced by students in Science Journalism (MASC 491-005), which was taught during the Fall 2016 semester by Jeff South, an associate professor in the Robertson School of Media and Culture at Virginia Commonwealth University, and Sara Williams, head of academic outreach for VCU Libraries.

The course, VCU’s first focusing exclusively on science reporting, was supported by a grant that funds projects aligned with VCU’s strategic plan, called Quest for Distinction. VCU selected the Science Journalism course as a “disruptively innovative idea” and as a way …

Short-Term Effects Of Nutrients On A Barrier Island Grassland Community, Ashley Moulton

Theses and Dissertations

Increased nutrient availability globally has the potential to affect community functional composition of plants in nutrient limited environments, such as coastal grassland systems. Stability of these systems are threatened worldwide by urbanization, as well as effects of sea level rise and increased frequency and intensity of storms, and atmospheric N deposition, associated with climate change. Annual net primary productivity (ANPP), species composition, and functional traits (community weighted specific leaf area (CWSLA), leaf area index (LAI), growth form and photosynthetic pathway) were measured across four treatments to assess multiple resource limitation of nitrogen (N) and phosphorus (P) and functional community response …

Effects Of Prescribed Fire On Cope’S Gray Treefrog (Hyla Chrysoscelis) Across Habitat Scales And Life Stages, Logan Mcdonald

Theses and Dissertations

Fire may alter both aquatic and terrestrial habitat used by all amphibian life stages, yet, our knowledge of its effects on amphibians is primarily limited to adult responses. I present an integrated approach to test the response of Cope’s Gray Treefrog (Hyla chrysoscelis) to fire by examining responses in tadpole performance and survivorship, adult abundance, and oviposition. Tadpoles raised with burned leaf litter had similar survival, but total mass and total length were 440% and 170% greater, respectively, for tadpoles raised in unburned litter. I assessed terrestrial and aquatic oviposition cues by embedding burned and unburned litter treatments within burned …

A Comparative Analysis Of Geometric Morphometrics Across Two Pseudemys Turtle Species In East Central Virginia, Kristin C. Dillard

Theses and Dissertations

The phylogeny of the turtle genus Pseudemys is poorly understood. In Virginia, many turtles have been found with indicator traits of both eastern river cooters (Pseudemys concinna concinna) and northern red bellied cooters (Pseudemys rubriventris). This study explores morphological evidence for hybridization between the two species across three riverine sites in east central Virginia.

Museum voucher groups for each species were analyzed for relative shell height and plastron length. The shape of the plastral scutes and upper jaw were analyzed using landmark-based morphometric software. These metrics were compared with measurements taken from 188 field-caught Pseudemys specimens. …

Deletion Of Cardiac Mir-17-92 Cluster Increases Ischemia/ Reperfusion Injury Via Pten Upregulation, Meeta B. Prakash

Theses and Dissertations

The miR-17- 92 cluster is necessary for cell proliferation and development of the cardiovascular system. Deletion of this cluster leads to death in neonatal mice. The role of this cluster still needs to be defined following ischemia and reperfusion. Methods and Results: Adult male mice were injected with Tamoxifen- was to induce inducible cardiac-specific miR-17- 92-deficient (miR-17- 92-def: MCM:TG:miR-17- 92 flox/flox ) and wild type (WT: MCM:NTG:miR-17-92 flox/flox ) mice were subjected to 30 minutes of myocardial ischemia via left anterior descending coronary artery ligation followed by reperfusion for 24 hours. Post I/R survival (48%) and ejection fraction were reduced, …

A Study Of Sediment Accretion Dynamics In Mature And Restored Tidal Freshwater Forested Wetlands In The James River Watershed Using Surface Elevation Tables And Marker Horizons, Ronaldo Lopez

Theses and Dissertations

Sediment accretion and elevation change in tidal forests, and the corresponding ability of these wetlands to keep pace with sea-level rise (SLR), represent data gaps in our understanding of wetland sustainability. Surface Elevation Tables and marker horizons were installed in three mature tidal forests and a restored tidal marsh, allowing us to measure elevation change, accretion, and subsidence. Additionally, we measured predictor variables to test for their significance in explaining accretion and elevation change rates. Mean accretion at our sites was 11.67 +/- 3.01 mm yr^-1 and mean elevation change was -20.22 +/- 8.10 mm yr^-1, suggesting …

Quantifying Current Sediment Deposition, Legacy Sediments, And Pre-Impoundment Vertical Accretion And Carbon Dynamics Following Dam Removal In A Recently Restored Tidal Freshwater Wetland, Melissa J. Davis

Theses and Dissertations

Damming disrupts natural sediment flow to downstream resulting in legacy sediment accumulation. Legacy sediments have been well investigated in streams throughout the Piedmont region; however, there is no research of legacy sediments following dam removal in low-gradient Coastal Plain streams. Research objectives were to: characterize legacy sediments in a low-gradient stream restoration, quantify pre-impoundment accretion and carbon dynamics, and assess current sediment deposition rates via ¹⁴C analyses within sediment cores and sediment collection tiles. Carbon accumulation and accretion rates of modern tidal sediment have reached that of the tidal relic benchmark and current sediment deposition rates are similar between …

Pelagic Fish Diversity And Density On And Off Restored Oyster Reef Habitat, Danielle Mcculloch

Theses and Dissertations

The heterogeneity provided by structured habitats is important in supporting diverse and dense fish communities. The biogenic reefs created by the native Eastern Oyster, Crassostrea virginica, were once the dominant structural habitat in Chesapeake Bay, and have since declined to less than 1% of historic estimates. Conflicting results on the effects of oyster reef restoration on pelagic fish assemblages make further investigation necessary. Incorporating multiple sampling strategies may help elucidate oyster reef habitat influence on fish assemblages. This study used multi-panel gillnets, hydroacoustic technology, and day-night sampling to describe pelagic fish assemblages on and off oyster reef habitat in the …

Moderate Severity Disturbance Has Similar Effects On The Production Of Three Forests Nested Within The Upper Great Lakes Landscape, Benjamin Tai Sagara

Theses and Dissertations

Moderate severity disturbances, which only kill a subset of canopy trees (e.g., via insects, pathogens, and windthrow), are increasingly widespread, and can alter forest structure and production. Whether moderate severity disturbance similarly affects the net primary production (NPP) of different forest stands within inherently heterogeneous landscapes, however, is unknown. We experimentally disturbed three, 2-ha stands varying in forest structure and primary production, reducing stand basal area 38 to 66 % by stem girdling all mature early successional aspen (Populus) and birch (Betula). For nearly a decade, we examined how the forest stands restructured and recovered, and linked post-recovery physical and …

A Comparison Of Computational Methods For Estimating Estuarine Production And Respiration From Diel Open Water Dissolved Oxygen Measurements, Spencer Tassone

Theses and Dissertations

Diel dissolved oxygen (DO) data were used to characterize seasonal, inter-annual, and longitudinal variation in production and respiration for the James River Estuary. Two computational methods (Bayesian and bookkeeping) were applied to these data to determine whether inferences regarding DO metabolism are sensitive to methodology. Net metabolism was sensitive to methodology as Bayesian results indicated net heterotrophy (production < respiration) while bookkeeping results indicated net autotrophy (production > respiration). Differences in net metabolism among the methods was due to low seasonal variation in respiration using the Bayesian method, whereas bookkeeping results showed a strong correlation between production and respiration. Bayesian results suggest a dependence on allochthonous organic matter (OM) whereas …

Community Gardens: Exploring Race, Racial Diversity And Social Capital In Urban Food Deserts, Jennifer F. Jettner

Theses and Dissertations

Study purpose. The study examined race and racial diversity in community gardens located in Southern urban food deserts, as well as the capacity of community gardens to generate social capital and promote social justice. Methods. A mixed-methods approach was used to describe characteristics of gardeners and community gardens located in urban food deserts, and test Social Capital Theory hypotheses. A convenience sample of 60 gardeners from 10 community gardens was obtained. Data was collected using surveys and semi-structured interviews. Analyses. Univariate and bivariate statistics were used to describe gardeners and gardens. Leader rationales for garden characteristics were analyzed using thematic …

Effects Of Hydraulic Dredging And Vessel Operation On Atlantic Sturgeon Behavior In A Large Coastal River, Michael R. Barber

Theses and Dissertations

The tidal James River, a focus of VCU's Atlantic Sturgeon program, supports both commercial shipping and hydraulic dredging. These anthropogenic threats present documented but preventable sources of mortality to the endangered species. Using three separate VEMCO Positioning System (VPS) receiver arrays, spatial data of previously-tagged fish were collected. ArcGIS and Programita software were used to analyze fish spatial distributions in the presence and absence of potential threats, using additional data including automatic identification system (AIS) vessel locations, vessel passages compiled using camera footage, and dredge records provided by the US Army Corps of Engineers. The data showed a change in …

A Range-Wide Assessment Of Migratory Connectivity For The Prothonotary Warbler Using Stable Hydrogen Isotopes, Jessica Reese

Theses and Dissertations

Populations of many species of migratory birds are declining, and an understanding of how populations are linked between the breeding and nonbreeding grounds is necessary in order to determine drivers of declines. While all current tracking technologies to study the movements of small songbirds are limited by their coarse resolution, tracking birds by measuring stable isotopes in keratin offers an advantage because it requires only a single capture and is cost-effective, which leads to robust sample sizes. While this tracking method is accurate, stable hydrogen isotope values measured in feathers (δ²H_f) are known to be variable …

Behavioral Responses Of Sub-Adult Atlantic Sturgeon (Acipenser Oxyrinchus Oxyrinchus) To Electromagnetic And Magnetic Fields Under Laboratory Conditions, Andrew Mcintyre Iii

Theses and Dissertations

Electromagnetic fields (EMF) produced by high voltage (HV), submarine transmission cables leading from offshore wind energy generation facilities could affect foraging or migratory behaviors of electro-receptive fishes, including endangered Atlantic Sturgeon. However, no published studies have quantitatively evaluated the possible behavioral effects of EMF exposure on sturgeon during residence in coastal waters. This study evaluated behavioral responses by sub-adult Atlantic Sturgeon to electromagnetic and magnetic fields under controlled laboratory conditions. Fabricated EMF generators were used to emulate a range of field EMF conditions that migratory fishes could encounter in proximity to submarine HV sources. Sensor arrays and digital video recorders …

The Effect Of Chronic Nutrient Addition From Wastewater On Forest Ecosystems At The Rice Rivers Center, Michael Beck

Theses and Dissertations

Wastewater application to land can be a useful tool for mitigating impacts of nutrient enrichment on aquatic systems. A land application treatment system at VCU’s Rice Rivers Center in Charles City County, VA provided an opportunity to study the impact of wastewater addition on the biogeochemistry of forests representative of the Mid-Atlantic Coastal Plain. Nutrient concentrations in throughfall and leachate were measured at Treatment and Control sites to assess differences in nutrient deposition and retention. Wastewater amended plots from the Walter L. Rice education building received 20-fold (N) and 6-fold (P) higher inputs relative to Control plots and plots located …

Characterization Of Current And Historical Variations In Sediment Accretion And Carbon Dynamics At The Rice Rivers Center Kimages Creek Wetland Restoration, Melissa J. Davis, Christopher D. Gatens, Edward R. Crawford, Arif Sikder

Rice Rivers Center Research Symposium

Current research of freshwater wetland soils have assessed and reported smaller stocks of soil organic carbon in restored wetlands compared to reference natural wetlands. However, a majority of these studies focus on sites restored from agricultural draining of non-tidal depressional wetlands,whereas carbon and accretion dynamics in tidal freshwater wetlands restored via dam removal is poorly understood. The U.S. Army Corps of Engineers estimates over 80,000 dams greater than 6 feet and tens of thousands of smaller dams pepper the U.S., of which the majority are unsafe, old or no longer serve their intended purpose. Damming disrupts the natural flow of …

An Analysis Of Particulate Matter In Central Virginia, Elizabeth Garrett, Arif Sikder

Rice Rivers Center Research Symposium

Virginia is consistently rated as a state with high rates of asthma (Asthma and Allergy Foundation 2014). Although this respiratory disease has many causes, certain air pollutants can be a trigger. The EPA currently identifies, monitors, and regulates seven types of air pollutants. One of these pollutants, particulate matter, can occur both naturally and culturally. The primary anthropogenic cause of particulate matter is fly ash, which is formed during fossil fuel combustion. Different technology installed in the power plant can capture some of the fly ash but these methods are not entirely effective.

This study focused on estimating the ratio …

Rice Center Focuses On Restoring Wetlands, Chris Rubis

The Scope

Halfway between Richmond and Williamsburg, where Kimages Creek flows into the James River, lies the Inger and Walter Rice Center for Environmental Life Sciences. A restoration project aims to return the area to its original state as a wetland. The project began by removing a dam that had been blocking the flow of Kimages Creek since 1927.

Virginia Commonwealth University Commencement Program [2016], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.