Click on the title of a talk to view the abstract.
Breakfast: 9:00 am- 10:00 am
Lobby
Resilience Panel: 10:00 am- 11:00 am
Clark Hall 108; Individuals representing Environmental Sciences and other departments will attempt to define the scope of the resilience concept by discussing how resilience manifests itself in their research.
Poster session: 11:00 am- 1:00 pm
The poster session will take place in the Clark Hall Mural Room. Lunch will be served in the Clark Hall foyer at noon.
Nitrogen fixation as a nutrient input in a local permaculture farm. A. Gorsky, J. Galloway, H. EpsteinBiological nitrogen fixation (BNF) is the process in which atmospheric N is converted into forms of nitrogen that plants can take up. BNF can be an important input to agricultural systems and an alternative for mineral fertilizer use to minimize environmental impacts. This study examines the role and dynamics of BNF as an input to the overall nitrogen budget at Timbercreek Farm, a permaculture livestock farm, located in Albemarle County, Virginia. The contribution of BNF to the farm is estimated by applying linear relationships from Anglade et al. (2015) study by using N yield and dry matter data of the legumes surveyed on the farm, and secondly, from 15N isotopic analysis of the plant materials and soil. The study further examines the spatial variability of the potential of BNF across six pasture fields and the variability of N content in soils and foliage. Knowing the contribution and efficiencies of BNF is important in the overall management of nitrogen in agricultural systems.
Author affiliations: Department of Environmental Sciences, University of Virginia
The highly variable natural abundances in most stable isotopes in contrast to their standard elemental concentrations make their analysis particularly useful in many applications, particularly in chemical fingerprinting and the identification of source signatures. Usually, to obtain accurate nitrogen stable isotope data for a given portion of organic matter in the laboratory, isotope-ratio mass spectrometry (IRMS) is the analytical tool of choice. IRMS is very high in precision; however, sample run times and instrument calibrations are time consuming, costly and represent data from a single location on the Earth’s surface at a particular time and performed only in laboratory conditions. Alternatively, field based Fourier-Transform infrared spectroscopy (FTIR) based spectroscopy can be performed rapidly, at a lower cost, and provide geospatially robust data. Isotopic shifts within the infrared spectrum have traditionally been measured using lab based FTIR spectroscopy. Three major methods are employed here: a traditional approach of isotope measurement using IRMS, FTIR spectroscopy, and a nontraditional computational approach, all of which aim to quantify isotopic downshifts within the spectra of several plant pigments. This will provide researchers with faster and cheaper measurements that could cover broader areas and eventually be translated to use with airborne or space-based instruments in order to provide biogeochemical understanding at larger spatial scales not possible by current instrumentation and techniques.
Author affiliations: Department of Environmental Sciences, University of Virginia
A water budget for the pond at Timbercreek Farm is being established to calculate nitrogen fluxes for the farm. Surface inflows and outflows are determined frequently using the velocity-area method. Direct inputs of precipitation to the pond are measured with a rain gauge at the site, and the data are calibrated and conditioned with additional data from the Charlottesville-Albemarle Airport. Evaporation rates are calculated using the Hamon method using the collected precipitation data. Groundwater inflow and outflow are assumed to be small compared with the surface water flows and have been ignored. The average water flux into the pond for the period from May to November, 2015 was 4820 m3/week; 97.4% from the inflow stream and 2.6% from precipitation. The average water flux out of the pond was 5580 m3/week with 98.4% from stream flow and 1.6% from evaporation. This suggests that the most important parts of the water budget are the surface flow that has been measured in some capacity throughout the project starting in 2013. Approximately 760 m3/week more water was lost from the pond during the study period of 2015. While a loss of water volume in this period is not unexpected, the magnitude could indicate that the net groundwater inflow makes a more substantial contribution to the volume loss during the investigational period. Additionally continuous stage data are being gathered with pressure transducers so that better measures of inflow and outflow can be obtained as a base for nitrogen flux estimates.
Author affiliations: Department of Environmental Sciences, University of Virginia
A species of great economic and environmental value, the Maryland blue crab (Callinectes sapidus) is currently recovering from population declines related to overfishing and environmental factors. Simultaneously their ocean environment is changing, with increased CO2 diffusing into the waters and reacting with water to form carbonic acid. This is decreasing the pH of the ocean overall, with some reporting a decline from 8.2 pre-industrial to 8.1 currently, which is significant given the logarithmic nature of the pH scale. Some plankton have shown significant loss of mass in their shells as these lower pH levels dissolve the calcium carbonate matrix. This decreases their viability and increases mortality. Blue crab larvae are demersal plankton with potential exposure to increasing ocean acidification (OA). Only limited research has been conducted with a few planktonic species, with no published research showing blue crab larval responses to OA. However based on their inability to osmoregulate, I hypothesize OA will negatively affect their viability and increase their mortality. Therefore I propose to set up five tanks ranging from 8.0-7.6 pH, with a control tank at 8.1, and evaluate the effect on blue crabs’ calcium carbonate Zoeae and Megalopae shells. A known and equal amount of plankton will be placed in each tank in order to determine mortality rates. Calcium content will be analyzed on each deceased larvae, in addition to total length, height, and width from digital imagery. A secondary experiment will determine feed preference and its effect on mortality. One type of prey will be fed stable isotope C13 and deceased blue crab larvae will be tested for isotope ratios to discover preference.
Author affiliations: Department of Environmental Sciences, University of Virginia
In analyzing water quality dynamics in inland aquatic ecosystems, dissolved organic nitrogen (DON), including proteins, enzymes, DNA, and various other types of organic nitrogen-bearing compounds, is one of the important factors to consider as it is present in all forms of life. This study focused on the seasonal and spatial variation of surface water DON in the pond and surrounding streams of Timbercreek Farm, a permaculture livestock farm in central (Charlottesville) Virginia. Water samples were chemically analyzed using the Lachat Automated Ion Analyzer. A key finding of this study was that DON concentrations in the outflow of the pond increased from 10% to 52% of the total dissolved nitrogen (TDN) from April to July of 2015, but then decreased from 52% to 14% of TDN from July of 2015 to January of 2016. This was mainly accredited to biological activity within the pond – more specifically, the accumulation of biomass associated with increased epilimnetic primary productivity in the summer relative to the spring and the winter. Contrary to many other lentic ecosystems of Virginia, the DON of the pond at Timbercreek Farm exhibited consistently low %DON of TDN (with a peak value of 52% in July). This was explained by the agriculture history of the land before the establishment of Timbercreek Farm in 2011 – the lower %DON values being attributed to residual nitrogen in the system (stored in the soils and sediments).
Author affiliations: Department of Environmental Sciences, University of Virginia
Sea level rise and human population growth amplify coastal erosion problems for many marshes along the Eastern Shore of Virginia. A small marsh island – Man and Boy Marsh – in the Virginia Coast Reserve was studied to determine long-term rates of change and to investigate spatial variations in erosional processes around the entire marsh island shoreline. Man and Boy Marsh is also the site of two artificial oyster reefs – on the south and east sides – installed by The Nature Conservancy (TNC) in 2015 to increase oyster habitat and to dampen wave energy driving erosion of the marsh edge. Given the erosive capacity of wave attack on marsh boundaries, reducing wave height and energy, known as wave attenuation, is a crucial component of any coastline protection plan. Nature-based shoreline modifications (e.g., living shorelines), like those installed by TNC at Man and Boy Marsh, offer a promising management treatment that preserves natural conditions while controlling erosion. Shoreline erosion rates were calculated using historical aerial photographs and a statistics software package, Analyzing Moving Boundaries Using R (AMBUR). Analysis of Man and Boy South Site (before the artificial reef installation) indicated an average rate of lateral erosion of 1.32 m year-1 while Man and Boy East Site experienced higher rates at 2.24 m year-1. Wave measurements at the two sites allow us to begin to determine what factors associated with orientation (e.g., prevailing winds, wind speed, and wave fetch) are affecting this spatial variation in wave conditions and erosion rates. Continued monitoring of erosion rates at Man and Boy Marsh will provide a quantitative assessment of the efficacy of TNC’s nature-based shoreline protection method.Author affiliations: Department of Environmental Sciences, University of Virginia
As a result of agricultural practices, excess nutrients are released into the environment, and can be detrimental to local habitats and water sources surrounding the farm. Farm scale budgets for nutrients, commonly in excess due to agricultural practices, have been calculated for various types of farms (conventional, organic, and permaculture), as an attempt to gauge the effect that a farm has on the surrounding environment due to the release of excess nutrients. Relative to conventional agricultural practices, permaculture is generally regarded as a more sustainable form of agriculture, due to more natural nutrient sources, but there are a limited number of nutrient budget studies done on permaculture farms.
While there have been studies that calculate the nitrogen budget of permaculture farms, there is a lack of literature on the phosphorus budget for permaculture farms. The purpose of this study is to create a phosphorus budget for a permaculture farm in Charlottesville, Virginia, and to determine where this specific permaculture farm falls on a spectrum of P budgets relative to conventional and organic farms. Initial findings indicate that pigs and chickens create a large P surplus relative to the P input, but that this surplus decreases over a 4 year time period as the P use efficiency (PUE) increases. From 2012 to 2015, the PUE for pigs and chickens increases from 24.4% in 2012 to 48.1% in 2015. As data pertaining to the cows becomes available, it is expected that the cow and whole farm P budget will show similar trends in increased PUE over 4 years.
Author affiliations: Department of Environmental Sciences, University of Virginia
Climate change is altering the extent and function of global forests. The Siberian boreal forests have experienced the greatest modification in regional climate, and are experiencing increasing amounts of stress and disturbances, including wildfires and insect outbreaks. Modeling the effect of changing disturbance frequencies and intensities on the boreal ecosystem functioning is important for understanding how these forests may change in the near future (decades to centuries). There is the possibility of southern boreal forest dying out due to stress and increased disturbance pressures in the next several decades.
We present a new disturbance module (DISTURB) developed for application with a spatially-explicit individual-based gap dynamics model SIBBORK. This module simulates the effect of disturbances on a forested landscape. In general, a disturbance, such as a fire or an insect outbreak, either kills or damages (stresses) individual trees, based on their species-specific tolerance to the disturbance type. This alters the species composition, the albedo, the radiation budget and hydrologic properties of the forest. Within species, individual trees may be more susceptible to mortality from a disturbance event based on age or stress from insufficiency of environmental resources. The module DISTURB operates in two modes: probabilistic and spatially-explicit. Within the probabilistic mode, disturbances can be simulated as a probability based on observed frequency, or triggered by an environmental condition, such as drought. Within the spatially-explicit mode, the disturbance has the ability to propagate across the simulated landscape. The propagation is facilitated by a multiplier that increases the probability that a disturbance will occur on a given plot if an adjacent plot is affected. These nuances are generally absent from existing disturbance modules and no spatially-explicit analog exists. This presents an important improvement in the simulation of boreal forest functionality under climate change and helps us understand the potential near-future shifts in forest composition.
Author affiliations: Department of Environmental Sciences, University of Virginia
The water footprint (WF) for the University of Virginia accounts for both the direct and indirect water use of activities and operations on the main campus of the university for calendar year 2014. It identifies materials that are purchased on an annual basis, including food, utilities, and materials such as paper. It excludes construction and furniture which have a multi-year lifespan. Data were retrieved from UVa Dining Services, Facilities Management, and the Procurement Office. Virtual water factors were cited from the Water Footprint Network and recent scientific literature. Initial results suggest that purchased electricity has a virtual WF of 6.9 million m³ water, food constitutes 4.3 million m³ virtual water, the on-Grounds heating plant has a virtual WF of 1.3 million m³ water. Transportation, feed for research animals, and paper constitute 1.4 million m³ virtual water. A brief comparison of conservation-minded student practices vs. the disposable-oriented alternative was conducted, using factors such as reusable water bottles versus disposable water bottles. Initial results suggest that traditionally conservation-motivated practices have half the water footprint of the disposable alternative over the duration of a student’s four-year college career. The water footprint of the University of Virginia is an especially useful tool alongside the University’s carbon and nitrogen footprints as it addresses another dimension of the environmental implications of the institution’s resource demands.
Author affiliations: Department of Environmental Sciences, University of Virginia
The eastern oyster, Crassostrea virginica, is a filter feeding organism that can strongly affect the environment in which it lives, including removal of suspended particulate matter from the water column and enhancement of benthic fluxes of carbon, nitrogen and phosphorus. As a result, oyster reefs can make a substantial contribution to total benthic oxygen uptake. Within the Virginia Coast Reserve (VCR), The Nature Conservancy (TNC), in partnership with state and federal agencies, are conducting large-scale efforts to restore C. virginica reefs. Due to their complex ecosystem structure, quantifying restoration success has proven difficult. In combination with population measurements, we are quantifying the benthic oxygen flux to determine net ecosystem respiration in order to quantify how closely restoration reefs are functioning like native reefs. Aquatic eddy covariance measurements of oxygen fluxes were made over several reefs of varying health and over an adjacent mud flat. Preliminary data suggest that oxygen uptake is approximately 10 times higher for a healthy oyster reef compared to an adjacent mud flat, suggesting that oyster reefs have the potential to sequester large amounts of carbon as they grow and develop. As more data become available, we will be able to further quantify the functioning of oyster reefs as well as the success of restoration efforts within the VCR.
Author affiliations: Department of Environmental Sciences, University of Virginia
Isoprene is a reactive hydrocarbon emitted by the biosphere. The lifetime of isoprene against oxidation is less than an hour on a typical summer day, with the most important oxidant typically being the hydroxyl radical (OH). The concentration of OH and the production of ozone, a harmful pollutant, are linked through complex photochemistry that varies nonlinearly with nitrogen oxides (NOx), hydrocarbons, such as isoprene, and temperature. As a result, emission controls to reduce ozone are expected to have also altered OH. While there are no long-term measurements of OH, we consider the OH response to reductions in reactive emissions in urban atmosphere through an analysis of trends in isoprene and ozone, as a function of NOx and temperature.
Author affiliations: Department of Environmental Sciences, University of Virginia
Recent advancements in electronics are allowing the development of low-cost unmanned aerial vehicles (UAV) for studying atmospheric structure and dynamics. While previous emphasis has been on the development of fixed wing unmanned aircraft for atmospheric investigations, the use of multi-rotor copters is relatively unexplored. The purpose of this research is to estimate wind velocity with 1) a direct approach using a sonic anemometer mounted above a hexacopter and 2) an indirect approach using attitude data from a quadrotor UAV. The data are collected by multi-rotor hovering in the center of three towers with sonic anemometers installed at 10m above ground. Initial results indicate that for both approaches, the estimated wind speeds from the copter show reasonable agreement with the winds from the sonic anemometer. The rotors had minimal influence (< 0.3 m/s) on the winds measured with the sonic anemometer above the copter frame. Due to the slow response of the copter to high frequency (~1Hz) changes in winds compared to the sonic anemometer, gusts are consistently underestimated using the indirect approach. Wind speed and direction averaged over 10 to 30 seconds show good agreement with sonic anemometer measurements.
Author affiliations: Department of Environmental Sciences, University of Virginia
Algal biofilms are an important fouling community on ship hulls, with severe economic consequences due to drag-induced increases in fuel use and cleaning costs. Here, we characterize the boundary layer flow structure in turbulent flow over diatomaceous slime, a type of biofilm. Diatomaceous slime composed of three species of diatoms commonly found on ship hulls was grown on acrylic test plates under shear stress. The slime averages 1.6 mm in thickness and has a high density of streamers, which are flexible elongated growths with a length on the order of 1- 2 mm located at the top of the biofilm that interact with the flow. Fouled acrylic plates were placed in a water tunnel facility specialized for detailed turbulent boundary layer measurements. High resolution Particle Image Velocimetry (PIV) data are analyzed for mean velocity profile as well as local turbulent stresses and turbulent kinetic energy (TKE) production, dissipation and transport. Quadrant analysis is used to characterize the impact of the instantaneous events of Reynolds shear stress (RSS) in the flow. To investigate the coherence of the large-scale motion in the flow two-point correlation analysis is employed.
Author affiliations:1Department of Environmental Sciences, University of Virginia2Department of Naval Architecture and Ocean Engineering, United States Naval Academy
Opening remarks 1 pm
Matthew Oreska and Lillian Aoki, Co-Chairs, EnviroDay 2016. Clark Hall 108.
Oral session 1: 1 pm- 2:00 pm
Clark Hall Room 108.
1:00- 1:15 pm Light pollution foils firefly courtship and mating. A. Firebaugh, K. Haynes
Author affiliations: Department of Environmental Sciences, University of Virginia.
Author affiliations: Department of Environmental Sciences, University of Virginia
Author affiliations: Department of Environmental Sciences, University of Virginia
Coffee Break 2:00 pm- 2:10 pm
Oral Session 2 (Resilience): 2:10- 2:55 pm
2:10- 2:25 pm Shocks to fishery production and trade J. Gephart
Author affiliations: Department of Environmental Sciences, University of Virginia
Author affiliations: Department of Environmental Sciences, University of Virginia
Operating at the loci of performance studies, spatial theory, cultural geography and urban ecology, this project aims to highlight the public practice of capoeira as both a mediator for, and expression of, the body and community in global urban space. Utilizing a critical reading of the theories of Henri Lefebvre and Edward Soja, this paper demonstrates the potential which bodies playing capoeira have for occupying and redefining the environment, both in the public and digital realms. It also argues that due to this new understanding of the body¬city relationship, capoeira should be implemented in youth outreach programs as a way to facilitate positive and creative relationships between children and the urban form, interactions which are generally overlooked within the field of child development.
Coffee Break 2:55 – 3:05 pm
Oral Session 3: 3:05 – 3:50 pm
3:05- 2:20 pm Interseasonal and interannual variability in CO2 emissions from Indonesian peatlands E. Swails
Author affiliations: Department of Environmental Sciences, University of Virginia
Coffee Break 3:50 – 4 pm
Keynote Seminar: 4- 5 pm. “The Future of Cities: Addressing challenges from the collision of urbanization and climate change”
Dr. Nancy Grimm, Director of the Central Arizona-Phoenix Long-term Ecological Research ProjectClosing remarks and Awards 5 pm
Matthew Oreska and Lillian Aoki, Co-Chairs, EnviroDay 2015. Clark Hall 108.
Social: 5:10- 7:30 pm
Odum Room