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Virginia Commonwealth University Courses [2016], Virginia Commonwealth University

VCU Bulletins

Listing of courses for the 2016-2017 year.

Virginia Commonwealth University Graduate Bulletin [2016], Virginia Commonwealth University

VCU Bulletins

Graduate bulletin for Virginia Commonwealth University for the academic year 2016-2017. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for graduate programs.

Greenhouse Gas Emissions Over A Tidal Cycle In A Freshwater Wetland, Joseph C. Morina, Rima B. Franklin

Rice Rivers Center Research Symposium

Tidal freshwater wetlands are located at the interface of non-tidal freshwater riverine systems and estuarine tidal systems. These habitats experience freshwater tides, creating unique redoximorphic soil characteristics while simultaneously presenting an opportunity for hydrologic nutrient transport into the system. Because of this periodic flooding and draining, tidal freshwater wetlands are systems of intense biogeochemical transformations, which are microbially mediated. Several microbial transformations (e.g., methanogenesis, incomplete denitrification, and nitrification) result in the production of greenhouse gases (CO2, CH4, and N2O) at globally-significant levels. For example, wetlands are one of the greatest sources of methane on Earth, accounting for 20-33% of the …

Virginia Commonwealth University Undergraduate Bulletin [2016], Virginia Commonwealth University

VCU Bulletins

Undergraduate bulletin for Virginia Commonwealth University for the academic year 2016-2017. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for undergraduate programs.

Prothonotary Warbler Nestling Growth And Condition Inresponse To Variation In Aquatic And Terrestrial Preyavailability, Jenna C. Dodson, Nicholas J. Moy, Lesley P. Bulluck

Biology Publications

Aquatic prey subsidies entering terrestrial habitats are well documented, but little is known about the degree to which these resources provide fitness benefits to riparian consumers. Riparian species take advantage of seasonal pulses of both terrestrial and aquatic prey, although aquatic resources are often over-looked in studies of how diet influences the reproductive ecology of these organisms. Ideally, the timing of resource pulses should occur at the time of highest reproductive demand. This study investigates the availability of aquatic(mayfly) and terrestrial (caterpillar) prey resources as well as the nestling diet of the prothonotary warbler (Protonotaria citrea) at two sites along …

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

VCU Commencement Programs

No abstract provided.

Commercial Drone Research Takes Off At Vcu, Joe Forcier

The Scope

As microprocessors and mounted cameras have become smaller, unmanned aerial vehicles, commonly known as drones, have skyrocketed in popularity. But UAVs aren’t just child’s play. Researchers at VCU say the devices could be used in a range of beneficial ways, from inspecting bridges and searching for lost hikers to shooting documentaries and surveying land.

The Effects Of Tidal Forcing On Nutrient Fluxes In The Tidal, Freshwater James River Estuary, Va, Dana L. Devore

Theses and Dissertations

A 12-month study (January to December 2015) focused on the effects of tidal forcing on nutrient fluxes in the tidal, freshwater segment of the James River Estuary (JRE). Discrete sampling of nutrient chemistry and continuous monitoring of tidal discharge were used to determine the volume and timing of the tides, and differences in nutrient concentrations between incoming and outgoing tides. The goal of this study was to improve understanding of tidal influence on nutrient fluxes and their role in nutrient transport to the lower estuary. Results suggested that differences in nutrient concentrations between incoming and outgoing tides were small throughout …

Valuing Natural Space And Landscape Fragmentation In Richmond, Va, Lee Wyatt Carpenter

Theses and Dissertations

Hedonic pricing methods and GIS (Geographic Information Systems) were used to evaluate relationships between sale price of single family homes and landscape fragmentation and natural land cover. Spatial regression analyses found that sale prices increase as landscapes become less fragmented and the amount of natural land cover around a home increases. The projected growth in population and employment in the Richmond, Virginia region and subsequent increases in land development and landscape fragmentation presents a challenge to sustaining intact healthy ecosystems in the Richmond region. Spatial regression analyses helped illuminate how land cover patterns influence sale prices and landscape patterns that …

Genome Wide Epigenetic Analyses Of Araptus Attenuatus, A Bark Beetle, Chitra Seshadri

Theses and Dissertations

Phylogeographic studies have relied on surveying neutral genetic variation in natural populations as a way of gaining better insights into the evolutionary processes shaping present day population demography. Recent emphasis on understanding putative adaptive variation have brought to light the role of epigenetic variation in influencing phenotypes and the mechanisms underlying local adaptation. While much is known about how methylation acts at specific loci to influence known phenotypes, there is little information on the spatial genetic structure of genome-wide patterns of methylation and the extent to which it can extend our understanding of both neutral and putatively adaptive processes. This …

Seasonal Variation Of Fish And Macroinvertebrate Biomass Spectra In Southern West Virginia Streams, Andrew J. Kirk

Theses and Dissertations

The biomass size spectrum - the power-law scaling relationship between average individual size and total biomass - has often been studied in lake and marine ecosystems, but rarely in lotic systems. The objective of this study was to test for characteristic biomass spectra in small temperate streams. Seasonal fish and macroinvertebrate data, including population abundance and biomass estimates, were collected in three wadeable, southern West Virginia streams from October 2013 to May 2015. Fish abundances were estimated with 3-pass electrofishing (depletion) surveys and individuals were weighed in the field. Macroinvertebrates were collected with a Hess sampler and returned to the …

Upper Thermal Limits Differ Among Component Species In A Host-Parasitoid-Hyperparasitoid System, Kanchan A. Joshi

Theses and Dissertations

Among the predicted impacts associated with global climate change, warming is of special interest because the rates of physiological processes are temperature-dependent. Insects and other ectotherms are likely to be affected due to their limited ability to control body temperature. In this study, I measured the tolerance to extreme high temperatures, i.e., critical thermal maximum (CT_max), of component species in a tri-trophic system, including an herbivore (Manduca sexta), a primary larval parasitoid (Cotesia congregata) and a hyperparasitoid (genus Silochalcis). For wild insects, the parasitoid had the lowest CT_max, the hyperparasitoid had …

Plant Functional Trait And Hyperspectral Reflectance Responses To Comp B Exposure: Efficacy Of Plants As Landmine Detectors, Paul V. Manley Ii

Theses and Dissertations

At least 110 million landmines have been planted since the 1970s in about 70 nations, many of which remain in place today. Some risk of detection may be mitigated using currently available remote sensing techniques when vegetation is present. My study focused on using plants as phytosensors to detect buried explosives. I exposed three species representing different functional types (Cyperus esculentus (sedge), Ulmus alata (tree), Vitis labrusca (vine)) to 500 mg kg^-1 of Composition B (Comp B; 60/40 mixture of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT)), a commonly used explosive mixture, and measured functional traits and reflectance over …

Selecting Spatial Scale Of Area-Level Covariates In Regression Models, Lauren Grant

Theses and Dissertations

Studies have found that the level of association between an area-level covariate and an outcome can vary depending on the spatial scale (SS) of a particular covariate. However, covariates used in regression models are customarily modeled at the same spatial unit. In this dissertation, we developed four SS model selection algorithms that select the best spatial scale for each area-level covariate. The SS forward stepwise, SS incremental forward stagewise, SS least angle regression (LARS), and SS lasso algorithms allow for the selection of different area-level covariates at different spatial scales, while constraining each covariate to enter at most one spatial …

Dimension Reduction And Variable Selection, Hossein Moradi Rekabdarkolaee

Theses and Dissertations

High-dimensional data are becoming increasingly available as data collection technology advances. Over the last decade, significant developments have been taking place in high-dimensional data analysis, driven primarily by a wide range of applications in many fields such as genomics, signal processing, and environmental studies. Statistical techniques such as dimension reduction and variable selection play important roles in high dimensional data analysis. Sufficient dimension reduction provides a way to find the reduced space of the original space without a parametric model. This method has been widely applied in many scientific fields such as genetics, brain imaging analysis, econometrics, environmental sciences, etc. …

Reproductive Success Of A Neotropical Migratory Songbird In Response To A Changing Climate, Ashley Grupenhoff, Lesley Bulluck

UROP Posters

Climate change is of rising concern especially due to how and if this changing climate affects individual species and their fitness. Migratory species, especially long-distance migrants, are ideal models for exploring the relationship between warming temperatures on temperate breeding grounds and decreased precipitation on tropical wintering areas. Few studies have long term data sets to observe species-specific assessments of fitness in relation to changing precipitation and temperature patterns, and those that have assessed these relationships show inconsistent results. We analyzed long-term data of a neo-tropical migratory songbird (Protonotaria citrea) to assess the potential relationships between indices of reproductive …

Influence Of Historic Landscapes And Contemporary Species Management On Chesapeake Bay Bald Eagles And Osprey, Catherine B. Viverette

Theses and Dissertations

Influence of historic landscapes and contemporary species management on Chesapeake Bay Bald Eagles and Osprey

Catherine B. Viverette

Co-distributed species with well documented demographic histories can provide good models for testing alternative hypotheses about the impact of evolutionary history, contemporary landscapes, and species management on current distribution and population structure. The Osprey (Pandion haliaetus) and Bald Eagle (Haliaeetus leucocephalus) have been extensively studied, managed and monitored across their North American breeding range, particularly in the Chesapeake Bay. We used a combination of ecological niche modelling, diet reconstruction, and population genetic modeling to understand the role of …

Commonwealth Times 2015-04-13

Commonwealth Times, 1969-

No abstract provided.

Commonwealth Times 2015-03-23

Commonwealth Times, 1969-

No abstract provided.

Emergent Non-Consumptive Predator Effects Alter Habitat Colonization By Mosquitoes, Ethan G. Staats, Salvatore J. Agosta, James R. Vonesh

Rice Rivers Center Research Symposium

Top-down consumptive control (suppression) is an important driver of populations and communities of prey organisms. Diverse predator assemblages often yield non-linear suppression with respect to constituent species' effects (emergence); most often diversity enhances suppression. Predators also affect prey organisms non-consumptively through changes in prey physiological, physical, spatial, temporal, and behavioral responses to predators. Role of predator diversity in non-consumptive response by prey is relatively un-studied. Role of predator diversity in shaping prey populations and communities through habitat colonization is a novel question.

Vegetation Structure Of Mangrove Ecosystems In Panama, Christopher L. Arrington, Cole Gandee, Spencer R. Parkinson

Rice Rivers Center Research Symposium

Mangroves provide important habitat for terrestrial and marine wildlife. They buffer shorelines from flooding and sequester excess nutrients and pollutants in runoff before reaching rivers and oceans. Mangroves provide a wintering habitat for migratory bird species. These habitats are being rapidly lost to coastal development. This research focused on assessing the vegetation structure of mangrove ecosystems in Panama.

Virginia Commonwealth University Courses [2015], Virginia Commonwealth University

VCU Bulletins

Listing of courses for the 2015-2016 academic year.

Virginia Commonwealth University Undergraduate Bulletin [2015], Virginia Commonwealth University

VCU Bulletins

Undergraduate bulletin for Virginia Commonwealth University for the academic year 2015-2016. It includes information on academic regulations, degree requirements, course offerings, faculty, academic calendar, and tuition and expenses for undergraduate programs.

Virginia Commonwealth University Graduate Bulletin [2015], Virginia Commonwealth University

VCU Bulletins

No abstract provided.

Algal Toxins In The Food Chain – A Comparative Study Of Chesapeake Bay And Baltic Coastal Food Webs, Spencer Tassone, Jūratė Lesutienė, Zita Gasiūnaitė, Linas Ložys, Renata Pilkaitytė, Žilvinas Pūtys, Paul A. Bukaveckas

Rice Rivers Center Research Symposium

Microcystin (MC) is a hepatotoxin produced by cyanobacteria (blue-green algae) which is found globally in eutrophic waters including lakes, lagoons and estuaries (Paerl and Paul 2012). The presence of MC in food webs is of concern due to adverse effects on biota and exposure to humans via commercial and recreational fisheries (Paerl and Otten 2013). Little is known regarding the factors which determine MC accumulation in food webs. We hypothesized that dietary exposure would be determined in part by sources of organic matter supporting the food web. We undertook a comparative study of the James River Estuary, a sub-estuary of …

Understanding Host-Switching By Ecological Fitting, Sabrina B. L. Araujo, Mariana Pires Braga, Daniel R. Brooks, Salvatore J. Agosta, Eric P. Hoberg, Francisco W. Von Hartenthal, Walter A. Boeger

Biology Publications

Despite the fact that parasites are highly specialized with respect to their hosts, empirical evidence demonstrates that host switching rather than co-speciation is the dominant factor influencing the diversification of host-parasite associations. Ecological fitting in sloppy fitness space has been proposed as a mechanism allowing ecological specialists to host-switch readily. That proposal is tested herein using an individual-based model of host switching. The model considers a parasite species exposed to multiple host resources. Through time host range expansion can occur readily without the prior evolution of novel genetic capacities. It also produces non-linear variation in the size of the fitness …

Virginia Commonwealth University Fall Commencement Program [2015], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

Virginia Commonwealth University Commencement Program [2015], Virginia Commonwealth University

VCU Commencement Programs

No abstract provided.

A Baseline Study Of Edaphic Characteristics, Vegetation Structure, And Recruitment Of Native Baldcypress (Taxodium Distichum (L). Rich. Var. Distichum) In The Newly Restored Wetland Of The Vcu Rice Rivers Center, Melissa J. Davis, Matthew S. Schibner

Rice Rivers Center Research Symposium

In theory, the ideal of ecological restoration is to reestablish a completely functioning ecosystem, however restoration success is often elusive (Stanturf et al. 2001). There is a significant gap in the current research on the impacts of restoration management of restored wetlands on ecosystem functions, especially biogeochemical cycling (Bernal & Mitsch 2013). Furthermore, there are many questions about management techniques when it comes to ecological engineering versus self-design (Bernal & Mitsch, 2013). However, we do know that it is critical to understand the species' life history, habitat template, and spatio temporal scope when attempting to re-establish populations (Lake et al. …

Behavioral Observations: Foraging And Aggression Of Neotropical Migrants And Resident Birds In Panama, Jessica M. Johnston, Samuel B. King, Ryan A. Levering

Rice Rivers Center Research Symposium

Lyons suggests that foraging data in songbirds can be an indicator of food abundance, with higher attack rate= higher habitat quality; higher foraging speed= lower habitat quality (2005). Territorial behavior such as interspecific aggression among songbirds may also be related to food availability. Previous studies have documented variation in the extent of territorial and aggressive behaviors among resident and Neotropical migratory species on tropical wintering grounds. This research gathered foraging and aggression data at two coastal angroves sites in central Panama, one on the Caribbean Coast (Galeta) and one on the Pacific Coast (Juan Diaz-East). Foraging data was used an …