Physical Sciences and Mathematics Commons^™

2014 Chesapeake Bay Sav Coverage, Sav Data Administrator, Virginia Institute Of Marine Science

Data

Abstract: The 2014 Chesapeake Bay SAV Coverage was mapped from 1:24,000 black and white aerial photography and digital multispectral imagery with a 25cm GSD to assess water quality in the Bay. Each area of SAV was interpreted from the rectified photography and classified into one of four density classes by the percentage of cover. The SAV beds were entered into an SDE GIS fetaure class using the quality control procedures documented below. The dataset contains all SAV areas that were identified from the areas flown. Some areas that are presumed to contain no SAV were not flown. Some small beds, …

Lancaster County, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, Kory Angstadt, David Stanhope, Christine Tombleson, Karen Duhring, Alexander D. Renaud, Robert Isdell, Pamela Braff, Benjamin P. Weissman, Carl Hershner

Reports

The data inventory developed for the Shoreline Inventory is based on a three tiered shoreline assessment approach. This assessment characterizes conditions that can be observed from a small boat navigating along the shoreline or by using observations made remotely at the desktop using high resolution imagery. The three tiered shoreline assessment approach divides the shorezone into three regions:

• the immediate riparian zone, evaluated for land use

• the bank, evaluated for height, cover and natural protection

• the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes.

The 2015 Inventory for Lancaster County was generated using on-screen, digitizing …

City Of Portsmouth, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, Kory Angstadt, Karen Duhring, David Weiss, Carl Hershner

Reports

The data inventory developed for the Shoreline Inventory is based on a three tiered shoreline assessment approach. This assessment characterizes conditions that can be observed from a small boat navigating along the shoreline or by using observations made remotely at the desktop using high resolution imagery. The three tiered shoreline assessment approach divides the shorezone into three regions:

1) the immediate riparian zone, evaluated for land use; 2) the bank, evaluated for height, cover and natural protection; and 3) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes.

The 2015 Inventory for the City of …

Piecewisesem: Piecewise Structural Equation Modelling In R For Ecology, Evolution, And Systematics, Jonathan S. Lefcheck

VIMS Articles

Summary

1. Ecologists and evolutionary biologists rely on an increasingly sophisticated set of statistical tools to describe complex natural systems. One such tool that has gained significant traction in the biological sciences is structural equation models (SEM), a form of path analysis that resolves complex multivariate relationships among a suite of interrelated variables.

2. Evaluation of SEMs has historically relied on covariances among variables, rather than the values of the data points themselves. While this approach permits a wide variety of model forms, it limits the incorporation of detailed specifications. Recent developments have allowed for the simultaneous implementation of non‐normal distributions, random …

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Climate Change As Migration Driver From Rural And Urban Mexico, Raphael J. Nawrotzki, Lori M. Hunter, Daniel Runfola, Fernando Riosmena

Arts & Sciences Articles

Studies investigating migration as a response to climate variability have largely focused on rural locations to the exclusion of urban areas. This lack of urban focus is unfortunate given the sheer numbers of urban residents and continuing high levels of urbanization. To begin filling this empirical gap, this study investigates climate change impacts on US-bound migration from rural and urban Mexico, 1986–1999. We employ geostatistical interpolation methods to construct two climate change indices, capturing warm and wet spell duration, based on daily temperature and precipitation readings for 214 weather stations across Mexico. In combination with detailed migration histories obtained from …

Street-Level Predictive Modeling Of Nuisance Flooding Verified Via Crowdsourced App Data In Norfolk, Va, J. D. Loftis, H. V. Wang, D R. Forrest

Presentations

No abstract provided.

Stafford County Shoreline Management Plan, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Marcia Berman, Tamia Rudnicky, Karinna Nunez, Sharon Kileen

Reports

With approximately 85 percent of the Chesapeake Bay shoreline privately owned, a critical need exists to increase awareness of erosion potential and the choices available for shore stabilization that maintains ecosystem services at the land-water interface. The National Academy of Science published a report that spotlights the need to develop a shoreline management framework (NRC, 2007). It suggests that improving awareness of the choices available for erosion control, considering cumulative consequences of erosion mitigation approaches, and improving shoreline management planning are key elements to minimizing adverse environmental impacts associated with mitigating shore erosion. Actions taken by waterfront property owners to …

Estuarine Sediment Dynamics, C. T. Friedrichs

Presentations

No abstract provided.

Suspended Particulate Matter Longitudinal Survey – Currituck Sound, Nc; Oct 13-15, 2015, Cruise: Cs151013-15, Chsd Stations: S5566-5587, Grace M. Massey, Kelsey A. Fall

Data

Dataset consists of water column and bottom burst data, PICS, and light attenuation data collected as part of a 21 station longitudinal survey of the Currituck Sound, NC along a ~60 km transect northward from the Wright Memorial Bridge.

Re-Emergence Of The Harmful Algal Bloom Species Alexandrium Monilatum In The Chesapeake Bay: Assessing Bloom Dynamics And Potential Health Impacts, Sarah K.D. Pease, Kimberly S. Reece, Wolfgang K. Vogelbein

Presentations

Effective management of harmful algal blooms (HABs) within a region requires an understanding of species-specific HAB spatial and temporal distributions, bloom dynamics, as well as potential health impacts. In 2007, the southern Chesapeake Bay witnessed its first blooms of the HAB species Alexandrium monilatum. Since then, A. monilatum has bloomed in the region almost annually. A. monilatum produces the toxin ‘goniodomin A’ and is suspected in local mass mortalities of oyster larvae (Crassostrea virginica) grown for aquaculture and restoration projects. Representatives from Virginia’s multimillion dollar oyster aquaculture industry recently expressed great concern over A. monilatum impacts to their businesses; field …

Diel Vertical Distribution Patterns Of Zooplankton Along The Western Antarctic Peninsula, Patricia S. Thibodeau, John A. Conroy, Deborah K. Steinberg

Presentations

The Western Antarctic Peninsula (WAP) is a region that has undergone significant change over the past several decades due to unprecedented increases sea surface temperature and decreases in sea ice cover. The ongoing Palmer Antarctica Long-Term Ecological Research (PAL LTER) study shows that these environmental changes are significantly affecting the marine pelagic ecosystem along the WAP. The goal of this study was to analyze diel vertical distribution patterns of zooplankton along the WAP.

Effects Of Commercial Clam Aquaculture On Biogeochemical Cycling In Shallow Coastal Ecosystems, Annie E. Murphy, Iris C. Anderson, Mark W. Luckenbach

Presentations

The bivalve aquaculture industry is expanding worldwide; sustainability requires improved understanding of its interactions with the environment. As suspension feeders, bivalves, such as clams, reduce primary production through feeding, and thus dampen eutrophication. Additionally, enhanced rates of denitrification, the microbial removal of reactive nitrogen, have been reported in bivalve sediments due to increased organic matter supply through biodeposition; another potential, yet indirect, control on eutrophication. Simultaneously, bivalves can influence local ‘bottom-up’ effects on production by enhancing nutrient regeneration through excretion and microbial mineralization of biodeposits. At clam aquaculture sediments, respiration and nutrient regeneration rates were significantly higher compared to uncultivated …

Informing Social Decision Making: Physical Vulnerability To Sea Level Rise, Alexander D. Renaud, Karinna Nunez, Molly Mitchell, Carl Hershner

Presentations

Social indices on census tract and other geopolitical levels are increasingly being considered to inform decision making. In a flooding and sea level rise context, the likelihood of an area flooding is an important component of adaptation and the decision-making framework, however it is frequently modeled on a continuous scale. In our work, we have developed an index of physical vulnerability to flooding on a census tract scale, specifically designed to complement social vulnerability indices.

The Role Of Oyster In Nitrous Oxide Emissions From Oyster Reefs, Anne Arfkin, Ashley Smyth, Bongkeun Song

Presentations

Oyster microbiomes may play a significant role in the biogeochemical N cycle and N2O emissions in estuarine and coastal ecosystems. Rates of denitrification and N2O production were measured from live oysters and oyster shells collected at a coastal lagoon and a tidal estuary in the Chesapeake Bay. Live oysters had the highest rates of denitrification and N2O production in both study sites. This indicates that oysters are an import N remover and a N2O source in coastal ecosystems.

Quantifying Finfish And Blue Crab Use Of Created Oyster Reefs In The Lower Chesapeake Bay, Bruce W. Pfirrmann, Rochelle D. Seitz

Presentations

Structurally complex reefs created by the eastern oyster Crassostrea virginica provide a host of ecosystem services yet have experienced significant declines, prompting extensive restoration efforts. We investigate the use of created oyster reefs in the lower Bay by mobile finfish and blue crabs with field surveys and diet analysis. The results of this study provide insight into how restoration activities influence estuarine community dynamics and the provision of ecosystem services.

Structural Complexity And Location Affect The Habitat Value Of Restored Oyster Reefs, Melissa Karp, Rochelle Seitz

Presentations

Oyster reefs provide a suite of valuable ecosystem services, such as water filtration, nitrogen sequestration, and provision of habitat and foraging grounds. The global decline of these habitats has had negative economic and ecological impacts to coastal waters worldwide. In the Chesapeake Bay, < 1% of the historic oyster population remains and efforts to restore oyster populations and the services they provide have been increasing. Building reefs that successfully provide specific ecosystem services may require different techniques then previously used, and success may depend on reef morphology, location, and environmental conditions. Settling trays were embedded into previously restored oyster reefs that varied in their structural complexity (rugosity) in multiple rivers in the lower Chesapeake Bay. Trays were collected after 7-weeks, sorted, and species identified and weighed (ash-free dry weight) to obtain species diversity, abundance, and biomass. Species composition data was analyzed using nMDS plots, which showed that salinity was an important driver of differences in species composition. Results of an ANOVA analysis found that species diversity was significantly greater on reefs in the high-salinity rivers compared to reefs in low-salinity rivers. Total organism abundance and biomass were positively correlated with reef structural complexity measures, such as rugosity, oyster clump volume, and oyster biomass. These results suggest that more complex oyster reefs in higher salinity locations may support more diverse and productive benthic communities. This study provides insight into the driving factors that structure oyster reef communities and has important implications for oyster reef restoration design and management.

The Relationship Between Reproduction And Mortality In Triploid Crassostrea Virginica: A Matter Of Economic Importance, Joseph L. Matt, Standish K. Allen

Presentations

The goal of this project is to maximize survival for commercially produced triploid Crassostrea virginica oysters in Virginia. Over the last few years, commercial oyster growers in Virginia have reported significant mortality events of triploid oysters during the spring and summer months. The summer of 2014 was the worst yet, as growers across the state reported summer mortality, most severe on the Eastern shore and in some cases as high as 85% of the crop (Karen Hudson, personal communication). Surviving oysters from some of these mortality events were sent to the Virginia Institute of Marine Science and several of the …

James City County Shoreline Management Plan, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Marcia Berman, Tamia Rudnicky, Karinna Nunez, Sharon A. Killeen

Reports

Actions taken by waterfront property owners to stabilize the shoreline can affect the health of the Bay as well as adjacent properties for decades. With these long-term implications, managers at the local level should have a more proactive role in how shorelines are managed. James City County recognizes that its natural environment is one of its most valuable assets as well as its most vulnerable (James City County, 2015). The shores of James City range from exposed open river to very sheltered creeks, and the nature of shoreline change varies accordingly (Figure 1-1). This shoreline management plan is useful for …

Wallops Assateague Chincoteague Inlet (Waci) Geologic And Coastal Management Summary Report, C. Scott Hardaway Jr., Donna A. Milligan, Christine A. Wilcox, Curtis Smith

Reports

No abstract provided.

Tidal Flat Morphodynamics: A Synthesis, C. T. Friedrichs

Presentations

No abstract provided.

Controls On Suspended Particle Properties And Water Clarity Along A Partially-Mixed Estuary, York River, Virginia, Usa, K. A. Fall, C. T. Friedrichs, G. M. Cartwright, D. G. 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 over the last 20 years has continued to deteriorate in the Bay and its tributaries (Williams et al., 2010). Analysis of long-term monitoring data (Wang et al., 2010) found that the concentration of total suspended solids (TSS), the regulatory indicator of ‘suspended sediment pollution’, is about as likely to be positively or negatively correlated to sediment loads …

Identification Of Suspended Resilient Pellets In Particles Tracked By A Particle Image Camera System (Pics) In A Muddy Estuary, Grace M. Cartwright, Kelsey A. Fall, Carl T. Friedrichs

Presentations

The Particle Imaging Camera System (PICS) was designed to allow for the measurement of the settling velocity of individual particles in situ by using the smaller particles (< density < 1800kg/m3 ). This classification system, while adequate for suspended dredge plumes, needs to be revisited when the PICS is used in a muddy estuary, such as the York River Estuary, Virginia. Figure 1B shows the settling velocities of particles tracked within a video captured 2.5m from the surface in the Clay Bank region of the York River, plotted against their equivalent spherical diameters. While most of the particles are classified as flocs, as indicated by the blue dots in Figure 1C and the peak in the relative number of particles in Figure 1E, there is still a large number of particles classified as “bed aggregates” (red dots). This number of higher density particles may be unexpected, as this video was captured 4.25m over a “muddy bed” in a natural system with a flood current of 40cm/s. However, biologically compacted mud in the form of resilient pellets (see Figure 2) may be the answer. Bed sediments from five sediment cruises during this study period (Aug 2012 – Nov 2014) were found to be comprised of 86-96% mud (Figure 3A). However, 9-14% of the mud was packaged as resilient pellets (Figure 3B). Sediment captured 38cm above the bed by traps deployed on tripods were found to have 92-98% mud, with 4-14% of the mud packaged as resilient pellets (Figures 3A and B). Pellets isolated from the Apr to Jul 2014 trap were sampled with the PICS to determine the distribution of settling velocities (Ws), particle densities, and the ratio of the long and short axis of the particles. This will be used to identify the pellets in PICS videos captured during the five 6h anchor stations (black lines in Figure 3) where three depths were sampled each hour.

Controls On Bed Erodibility In A Muddy, Partially-Mixed Estuary: York River, Virginia, Usa, Carl T. Friedrichs, Grace M. Cartwright, Patrick J. Dickhut, Kelsey A. Fall

Presentations

Appropriate parameterization of time-dependent erodibility of muddy seabeds is a significant barrier to improved understanding and accurate modelling 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 (e.g., Dickhudt et al., 2009, 2011; Kraatz, 2013). 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 (e.g. Friedrichs et …

Decadal Re-Evaluation Of Contaminant Exposure And Productivity Of Ospreys (Pandion Haliaetus) Nesting In Chesapeake Bay Regions Of Concern, Rs Lazarus, Ba Rattner, Pc Mcgowan, Robert Hale, Et Al

VIMS Articles

The last large-scale ecotoxicological study of ospreys (Pandion haliaetus) in Chesapeake Bay was conducted in 2000-2001 and focused on U.S. EPA-designated Regions of Concern (ROCs; Baltimore Harbor/Patapsco, Anacostia/middle Potomac, and Elizabeth Rivers). In 2011-2012, ROCs were re-evaluated to determine spatial and temporal trends in productivity and contaminants. Concentrations of p,p'-DDE were low in eggs and below the threshold associated with eggshell thinning. Eggs from the Anacostia/middle Potomac Rivers had lower total PCB concentrations in 2011 than in 2000; however, concentrations remained unchanged in Baltimore Harbor. Polybrominated diphenyl ether flame retardants declined by 40%, and five alternative brominated flame retardants were …

Evaluating Recruitment Of American Eel, Anguilla Rostrata, In The Potomac River (Spring 2015), Troy D. Tuckey, Mary C. Fabrizio

Reports

The Atlantic States Marine Fisheries Commission (ASMFC) adopted the Interstate Fishery Management Plan (FMP) for the American Eel in November 1999. The FMP focuses on increasing coastal states’ efforts to collect American Eel data through both fishery‐dependent and fishery‐independent studies. Consequently, member jurisdictions agreed to implement an annual survey for young‐of‐year (YOY) American Eels. The survey is intended to “…characterize trends in annual recruitment of the YOY eels over time [to produce a] qualitative appraisal of the annual recruitment of American Eel to the U.S. Atlantic Coast” (ASMFC 2000). The development of these surveys began in 2000 with full implementation …

Shoreline Evolution: Stafford County, Virginia Potomac River And Rappahannock River Shorelines, Donna A. Milligan, Christine A. Wilcox, C. Scott Hardaway Jr.

Reports

Stafford County is situated along the upper reaches of the Potomac and Rappahannock Rivers. Because the County’s shoreline is continually changing, determining where the shoreline was in the past, how far and how fast it is moving, and what factors drive shoreline change will help define where the shoreline will be going in the future. These rates and patterns of shore change along Chesapeake Bay’s estuarine shores will differ through time as winds, waves, tides and currents shape and modify coastlines by eroding, transporting and depositing sediments. The purpose of this report is to document how the shore zone of …

Stafford County, Virginia Shoreline Inventory Report Methods And Guidelines, Marcia Berman, Karinna Nunez, Sharon Killeen, Tamia Rudnicky, Julie Bradshaw, Karen Duhring, David Stanhope, David Weiss, Carl Hershner

Reports

The data inventory developed for the Shoreline Inventory is based on a three tiered shoreline assessment approach. This assessment characterizes conditions that can be observed from a small boat navigating along the shoreline or by using observations made remotely at the desktop using high resolution imagery. The three tiered shoreline assessment approach divides the shorezone into three regions:

1) the immediate riparian zone, evaluated for land use; 2) the bank, evaluated for height, cover and natural protection; and 3) the shoreline, describing the presence of shoreline structures for shore protection and recreational purposes.

The 2015 Inventory for Stafford County was …

Tidal Flat Morphodynamics: A Synthesis, Carl T. Friedrichs

Presentations

Tidal flats commonly occur along coasts where the tidal range is large relative to typical wave height. They can be found where hydrodynamic energy is high or low, where sediments are sandy or muddy, and where shorelines are prograding, retreating, or stable. The study of the morphology and evolution of tidal flats is particularly well suited in the context of morphodynamics since characteristics such as profile shape, bed slope, and grain size clearly and systematically vary as a function of sediment supply and wave and tidal forcing, and the nature of wave- and tide-induced velocities across tidal flats is, in …

Historical Summer Distribution Of The Endangered North Atlantic Right Whale (Eubalaena Glacialis): A Hypothesis Based On Environmental Preferences Of A Congeneric Species, Sophie Monserrat, Maria G. Pennino, Tim D. Smith, Randall R. Reeves, Christine N. Meynard, David M. Kaplan, Ana S.L. Rodrigues

VIMS Articles

Aim: To obtain a plausible hypothesis for the historical distribution of North Atlantic right whales (NARWs) (Eubalaena glacialis) in their summer feeding grounds. Previously widespread in the North Atlantic, after centuries of hunt- ing, these whales survive as a small population off eastern North America. Because their exploitation began before formal records started, information about their historical distribution is fragmentary.

Comt Chesapeake Bay Hypoxia Modeling, Marjorie A.M. Friedrichs, I. Irby, A. Bever, M. Scully

Presentations

No abstract provided.