Physical Sciences and Mathematics Commons^™

A Sonic Net Excludes Birds From An Airfield: Implications For Reducing Bird Strike And Crop Losses, John P. Swaddle, Dana L. Moseley, Mark H. Hinders, Elizabeth P. Smith

Arts & Sciences Articles

Collisions between birds and aircraft cause billions of dollars of damages annually to civil, commercial, and military aviation. Yet technology to reduce bird strike is not generally effective, especially over longer time periods. Previous information from our lab indicated that filling an area with acoustic noise, which masks important communication channels for birds, can displace European Starlings (Sturnus vulgaris) from food sources. Here we deployed a spatially controlled noise (termed a “sonic net”), designed to overlap with the frequency range of bird vocalizations, at an airfield. By conducting point counts, we monitored the presence of birds for four …

Virginia Shellfish Aquaculture Situation And Outlook Report : Results Of The 2015 Virginia Shellfish Aquaculture Crop Reporting Survey, Karen Hudson, Thomas J. Murrary

Reports

The hatchery-based shellfish aquaculture industry in Virginia continues to grow adding significant value to the Commonwealth’s seafood marketplace. Today, watermen harvest both hard clams and oysters from the Commonwealth’s public resources, albeit at rates diminished from historic levels. At the same time, Virginia’s watermen-farmers, utilizing production from a land-based hatchery, are providing additional quantities of quality shellfish to consumers. This survey, in its 10th year, is intended to continue annual assessments with which to gauge growth and inputs in Virginia’s hatchery-based shellfish aquaculture industry. This report is based upon an industry survey completed during the first quarter of 2016. While …

Unitary Limit Of Two-Nucleon Interactions In Strong Magnetic Fields, William Detmold, Kostas Orginos, Assumpta Parreño, Martin J. Savage, Et Al.

Arts & Sciences Articles

Two-nucleon systems are shown to exhibit large scattering lengths in strong magnetic fields at unphysical quark masses, and the trends toward the physical values indicate that such features may exist in nature. Lattice QCD calculations of the energies of one and two nucleons systems are performed at pion masses of mπ∼450 and 806 MeV in uniform, time-independent magnetic fields of strength |B|∼1019–1020  G to determine the response of these hadronic systems to large magnetic fields. Fields of this strength may exist inside magnetars and in peripheral relativistic heavy ion collisions, and the unitary behavior at large scattering lengths may have …

Controls On Suspended Particle Properties And Water Clarity Along A Partially-Mixed Estuary, York River, Virginia, Kelsey Fall, Carl Friedrichs, Grace M. Cartwright, David Bowers

Presentations

The Chesapeake Bay and its associated tidal tributaries, which together form one of the United States’ largest and most important estuaries, are among the many coastal systems where degraded water clarity is a major concern. Despite long-term decreases in sediment input, water clarity has continued to deteriorate in the southern Bay. Paradoxically, clarity has declined less in the northern Bay where riverine sediment load has recently increased. Here it is proposed that the disconnect between water clarity and sediment input is related to the dynamic nature of locally suspended estuarine particles, as well as the interaction between suspended organic particles …

What Controls Bed Erodibility In Muddy, Partially-Mixed Estuaries? Insights From The York River, Virginia, Carl Friedrichs, Grace M. Cartwright, P.J. Dickhudt, Kelsey Fall

Presentations

Appropriate parameterization of time-dependent erodibility of muddy seabeds is a significant barrier to improved understanding and accurate modeling of sediment dynamics in estuaries and other coastal regions. In an effort to better understand controls on muddy seabed erodibility, bed erodibility and associated bed sediment properties have been measured by our group on cores collected on dozens of cruises over the last decade in the York Estuary. We have also inferred time-varying erodibility indirectly in the York Estuary over several years by vertically integrating observations of tidally-varying suspended sediment concentration. This presentation synthesizes the results of these long-term observations in this …

Evaluating The Effects Of Cohesive Processes On Sediment Distribution In An Idealized, Partially-Mixed Estuary Using A Numerical Model, Danielle Tarpley, Courtney Harris, Carl Friedrichs

Presentations

An idealized two-dimensional model is designed to represent a longitudinal section of a partially-mixed estuary, accounting for a freshwater source, tides, and estuarine circulation, but neglecting across-channel variations. The Community Sediment Transport Modeling System (CSTMS) is used to simulate suspended transport, erosion, and deposition within the Regional Ocean Modeling System (ROMS). This version of the model also includes cohesive processes such as consolidation and swelling of the sediment bed; sediment-induced stratification; and variable settling velocities. To better understand the processes controlling fine-grained sediment transport in the York River, VA, the primary features of the idealized estuary mimic that system, and …

Challenges Associated With Modeling Low-Oxygen Waters In Chesapeake Bay: A Multiple Model Comparison, I.D. Irby, M. A.M. Friedrichs, Carl T. Friedrichs, Comt Estuarine Hypoxia Team

Presentations

As ecosystem and water quality models are becoming more frequently used for operational forecasts and scenario-based management decisions, it is important to understand the relative strengths and limitations of existing models of varying complexity. To this end, simulations of the Chesapeake Bay from eight threedimensional coupled hydrodynamic-oxygen models have been statistically compared to each other and to two years of historical monitoring data. Results show that although models have difficulty resolving the variables typically thought to be the main drivers of dissolved oxygen variability (stratification, nutrients, and chlorophyll), all eight models have significant skill in reproducing the mean and seasonal …

Captain Sinclair’S Recreational Area Shoreline Management Plan, Donna A. Milligan, C. Scott Hardaway Jr., Christine A. Wilcox

Reports

Captain Sinclair’s Recreation Area (CSRA) is located on the Severn River in Gloucester County, Virginia. It is a tract of land consisting of about 100 acres that was donated to the Middle Peninsula Chesapeake Bay Public Access Authority (Figure 1). Longterm goals for the property include active and passive recreational and research activities including several shoreline-based projects. The property has about 1.3 miles of tidal shoreline that extends from the canal on the northern end of the property, along Whittaker Creek, and to the Severn River down to small unnamed tidal creek adjacent to the old wood pier. Shoreline erosion, …

2016 Hampton Roads Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

Atlantic Coast And Inner Shelf, David E. Krantz, Carl H. Hobbs Iii, Geoffrey L. Wikel

VIMS Books and Book Chapters

The continental margin of Virginia, and of North America more broadly, is the physical transition from the high elevation of the continent to the low of the ocean basin. This transition was created as rifting pulled apart the ancient supercontinent Pangaea to create the Atlantic Ocean basin. Tectonic forces fractured and stretched the bedrock to create a stair-step ramp that subsequently would be mantled with sediment built up by erosion and transport off the continent.

The Coastal Plain and Continental Shelf of Virginia are contiguous and discrete physiographic provinces of the continental margin delimited by the present elevation of sea …

2016 Gloucester Point Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

2016 Chesapeake Bay Bridge Tunnel Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

2016 Wachapreague Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.

Combining Inverse And Transport Modeling To Estimate Bacterial Loading And Transport In A Tidal Embayment, Mac Sisson, Jian Shen, Anne Schlegel

VIMS Articles

Poquoson River is a tidal coastal embayment located along the Western Shore of the Chesapeake Bay about 4 km south of the York River mouth in the City of Poquoson and in York County, Virginia. Its drainage area has diversified land uses, including high densities of residence, agricultural, salt marsh land uses, as well as a National Wildlife Refuge. This embayment experiences elevated bacterial concentration due to excess bacterial inputs from storm water runoff, nonpoint sources, and wash off from marshes due to tide and wind-induced set-up and set-down. Bacteria can also grow in the marsh and small tributaries. It …

A Comparative Study Of Iron And Temperature Interactive Effects On Diatoms And Phaeocystis Antarctica From The Ross Sea, Antarctica, Zhi Zhu, Kai Xu, Feixue Fu, Jenna L. Spackeen, Deborah A. Bronk, David A. Hutchins

VIMS Articles

In the future, temperature and iron availability are predicted to change in the coastal polynyas of Antarctica, which are the most biologically productive regions of the Southern Ocean. We examined the individual and combined effects of iron addition (+500 nM) and temperature increase (4°C) on Phaeocystis antarctica and several dominant diatom species isolated from the McMurdo Sound sector of the Ross Sea. Iron addition increased growth, carbon fixation, iron uptake rates, cellular carbon quota, and cell size of almost all tested species, while temperature increase only affected certain species. Concurrent increases in temperature and iron synergistically stimulated the growth rates …

Prediction Of The Export And Fate Of Global Ocean Net Primary Production: The Exports Science Plan, Da Siegel, Ko Buesseler, Et Al, Deborah K. Steinberg

VIMS Articles

Ocean ecosystems play a critical role in the Earth's carbon cycle and the quantification of their impacts for both present conditions and for predictions into the future remains one of the greatest challenges in oceanography. The goal of the EXport Processes in the Ocean from Remote Sensing (EXPORTS) Science Plan is to develop a predictive understanding of the export and fate of global ocean net primary production (NPP) and its implications for present and future climates. The achievement of this goal requires a quantification of the mechanisms that control the export of carbon from the euphotic zone as well as …

A Carbon Budget For The Amundsen Sea Polynya, Antarctica: Estimating Net Community Production And Export In A Highly Productive Polar Ecosystem, Pl Yager, Rm Sherrell, Et Al, Rachel E. Sipler, Et Al

VIMS Articles

Polynyas, or recurring areas of seasonally open water surrounded by sea ice, are foci for energy and material transfer between the atmosphere and the polar ocean. They are also climate sensitive, with both sea ice extent and glacial melt influencing their productivity. The Amundsen Sea Polynya (ASP) is the greenest polynya in the Southern Ocean, with summertime chlorophyll a concentrations exceeding 20 μg L−1. During the Amundsen Sea Polynya International Research Expedition (ASPIRE) in austral summer 2010–11, we aimed to determine the fate of this high algal productivity. We collected water column profiles for total dissolved inorganic carbon (DIC) and …

Influence Of Wind Strength And Duration On Relative Hypoxia Reductions By Opposite Wind Directions In An Estuary With An Asymmetric Channel, Ping Wang, Harry V. Wang, Lewis Linker, Kyle Hinson

VIMS Articles

Computer model experiments are applied to analyze hypoxia reductions for opposing wind directions under various speeds and durations in the north–south oriented, two-layer-circulated Chesapeake estuary. Wind’s role in destratification is the main mechanism in short-term reduction of hypoxia. Hypoxia can also be reduced by wind-enhanced estuarine circulation associated with winds that have down-estuary straining components that promote bottom-returned oxygen-rich seawater intrusion. The up-bay-ward along-channel component of straining by the southerly or easterly wind induces greater destratification than the down-bay-ward straining by the opposite wind direction, i.e., northerly or westerly winds. While under the modulation of the west-skewed asymmetric cross-channel bathymetry …

Influence Of Reservoir Infill On Coastal Deep Water Hypoxia, Lewis C. Linker, Richard A. Batiuk, Carl F. Cerco, Gary W. Shenk, Richard Tian, Ping Wang, Guido Yactayo

VIMS Articles

Ecological restoration of the Chesapeake through the Chesapeake Bay total maximum daily load (TMDL) requires the reduction of nitrogen, phosphorus, and sediment loads in the Chesapeake watershed because of the tidal water quality impairments and damage to living resources they cause. Within the Chesapeake watershed, the Conowingo Reservoir has been filling in with sediment for almost a century and is now in a state of near‐full capacity called dynamic equilibrium. The development of the Chesapeake TMDL in 2010 was with the assumption that the Conowingo Reservoir was still effectively trapping sediment and nutrients. This is now known not to …

Primary Production In The Delta: Then And Now, James E. Cloern, April Robinson, (...), Elizabeth A. Canuel, Et Al

VIMS Articles

To evaluate the role of restoration in the recovery of the Delta ecosystem, we need to have clear targets and performance measures that directly assess ecosystem function. Primary production is a crucial ecosystem process, which directly limits the quality and quantity of food available for secondary consumers such as invertebrates and fish. The Delta has a low rate of primary production, but it is unclear whether this was always the case. Recent analyses from the Historical Ecology Team and Delta Landscapes Project provide quantitative comparisons of the areal extent of 14 habitat types in the modern Delta versus the historical …

Effects Of Resonant Magnetic Perturbations On Turbulence And Transport In Diii-D L-Mode Plasmas, Saskia Mordijck, T. L. Rhodes, L. Zeng, E. J. Doyle, Et Al.

Arts & Sciences Articles

In this paper we show that resonant magnetic perturbations (RMPs) affect the L- to H-mode power threshold. We find that during the L-mode phase, RMPs cause the particle pinch to reverse from traditionally inward to outward. As a result, the density at the plasma edge increases, while the density in the plasma core is reduced. Linear stability calculations indicate that the plasma transitions from an ion temperature gradient (ITG) to trapped electron mode (TEM) regime at the plasma edge. If the applied RMP current is below the threshold for penetration and island formation, we find that the changes in the …

A Precision Measurement Of The Weak Charge Of Proton At Low Q^2: Kinematics And Tracking, Siyuan Yang

Dissertations, Theses, and Masters Projects

The Standard Model of particle physics represents our present best understanding of the elementary particles and three of the four fundamental forces. One of the most important and challenging tasks of modern particle physics is to test, and perhaps, to find the evidence for new physics not contained in the Standard Model. One such test, the $Q_{weak}$ experiment, was conducted at JLab in Newport News, VA, from 2010 to 2012. The goal of the experiment is to measure the value of the weak charge of proton, $Q_{weak}$ to a 4\% precision, which, if it confirms the Standard Model prediction, will …

Why Biodiversity Is Important To The Functioning Of Real-World Ecosystems, Da Siegel, Ko Buessler, Et Al, Deborah K. Steinberg

VIMS Articles

Ocean ecosystems play a critical role in the Earth's carbon cycle and the quantification of their impacts for both present conditions and for predictions into the future remains one of the greatest challenges in oceanography. The goal of the EXport Processes in the Ocean from Remote Sensing (EXPORTS) Science Plan is to develop a predictive understanding of the export and fate of global ocean net primary production (NPP) and its implications for present and future climates. The achievement of this goal requires a quantification of the mechanisms that control the export of carbon from the euphotic zone as well as …

Development Of The Hydrodynamic Model For Long-Term Simulation Of Water Quality Processes Of The Tidal James River, Virginia, Jian Shen, Ya Wang, Mac Sisson

VIMS Articles

Harmful algal blooms (HABs) have frequently occurred in the James River. The State has convened a Scientific Advisory Panel (SAP) to review the James River chlorophyll-a standards. The SAP will conduct a scientific study to review the basis for setting the chlorophyll-a standards. To support the SAP study of chlorophyll-a standards, the State of Virginia has decided to develop a numerical modeling system that is capable of simulating phytoplankton and HABs. The modeling system includes a watershed model, a three-dimensional hydrodynamic model and water quality models. The focus of this study will be on the development and verification of the …

Summary Tables: Accomack County, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, Kory Angstadt, Christine Tombleson, Karen Duhring, Kallie Brown, Jessica Hendricks, David Weiss, Carl Hershner

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).

Summary Tables: City Of Chesapeake, Virginia Shoreline Inventory Report, Marcia Berman, Karinna Nunez, Sharon A. Killeen, Tamia Rudnicky, Julie Bradshaw, David Stanhope, Karen Duhring

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).

Summary Tables: Prince George County And The City Of Hopewell, Virginia Shoreline Inventory Report, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, David Stanhope, Karen Duhring, Jessica Hendricks, David Weiss, Carl Hershner

Reports

The Shoreline Inventory Summary Tables quantify observed conditions based on river systems, such as the combined length of linear features (e.g. shoreline miles surveyed, miles of bulkhead and revetment), the total number of point features (e.g. docks, boathouses, boat ramps) & total acres of polygon features (tidal marshes).

Local, Global, And Nonlinear Screening In Twisted Double-Layer Graphene, Chih-Pin Lu, Martin Rodriguez-Vega, (...), Enrico Rossi, Et Al.

Arts & Sciences Articles

One-atom-thick crystalline layers and their vertical heterostructures carry the promise of designer electronic materials that are unattainable by standard growth techniques. To realize their potential it is necessary to isolate them from environmental disturbances, in particular those introduced by the substrate. However, finding and characterizing suitable substrates, and minimizing the random potential fluctuations they introduce, has been a persistent challenge in this emerging field. Here we show that Landau-level (LL) spectroscopy offers the unique capability to quantify both the reduction of the quasiparticles' lifetime and the long-range inhomogeneity due to random potential fluctuations. Harnessing this technique together with direct scanning …

Zooplankton Community Composition And Grazing In The Amazon River Plume And Western Tropical North Atlantic Ocean, Brandon J. Conroy

Dissertations, Theses, and Masters Projects

Large river plumes and frontal zones are important physical features influencing plankton distribution in the marine environment. In the western tropical North Atlantic Ocean (WTNA) the Amazon River plume may extend over an area reaching 1.5 x 106 km2. The freshwater plume creates a low-density lens in the surface 25m and supplies silicon and phosphorus to the WTNA. These physical and chemical gradients create an ideal environment for large-scale blooms of diatom diazotroph associations (DDAs), a symbiotic relationship between nitrogen-fixing cyanobacteria and chain-forming diatoms. While the physical and chemical properties of the plume with regard to influences on phytoplankton have …

Biogeochemistry Of Redox-Sensitive Elements In The Subterranean Estuary, Alison E. O'Connor

Dissertations, Theses, and Masters Projects

Submarine groundwater discharge (SGD) is any flow of water along the continental margins from the seabed into the coastal ocean, and it represents an important source of nutrients and trace metals to the coastal ocean. The chemical composition of SGD is strongly influenced by biogeochemical reactions that take place within the subterranean estuary (STE), the subsurface mixing zone of fresh and saline waters. Understanding the reactions that take place within the shallow STE is critical to evaluating the composition of SGD, and therefore SGD-driven chemical fluxes. In this dissertation, I seek to determine the biogeochemical processes controlling the behavior of …