2016

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Biological 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

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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

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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

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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

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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

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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

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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

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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

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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 m^³ water, food constitutes 4.3 million m³ virtual water, the on-Grounds heating plant has a virtual WF of 1.3 million m^³ water. Transportation, feed for research animals, and paper constitute 1.4 million m^³ 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

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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

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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 (NO^x), 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 NO^x and temperature.
Author affiliations: Department of Environmental Sciences, University of Virginia

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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

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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

Though a number of effects of artificial light pollution on behavior and physiology have been described, there is little understanding of the consequences for the growth and distribution of populations. Here, we document potential impacts of light pollution on aspects of firefly population ecology. Many firefly species have a unique communication system where bioluminescent flashes are used in courtship displays to find and attract mates. We conducted a series of manipulative field studies to examine the effects of light pollution on firefly flashing activities, mating opportunities, dispersal, and abundances by experimentally adding artificial lights to previously dark firefly habitat. We show that light pollution reduces flashing activities in a dark-active firefly species (Photuris versicolor) and courtship behavior and mating success in a twilight-active species (Photinus pyralis). Our work generates predictions about how light pollution may affect firefly populations and contributes to larger discussions about the ecological consequences of sensory pollution.
Author affiliations: Department of Environmental Sciences, University of Virginia.

The storage and flux of terrestrial carbon (C) is one of the largest and most uncertain components of the global C budget, the vast majority of which is held within the biomass of the world’s forests. However, the spatial distribution and quantification of forest C remains difficult to measure on a large scale. Remote sensing of forests with airborne LiDAR has proven to be an extremely effective method of bridging the gap between data from plot-level forestry mensuration and landscape-scale C storage estimates, but the standard method of assessing forest C is typically based on national or regional-scale allometric equations that are often not representative on the local-scale. Improvement of these measurements is necessary in order for collaborative multi-national carbon monitoring programs such as REDD implemented by the UNFCCC to be successful in areas, such as tropical forests, with tree species that have insufficiently documented allometric relationships. The primary goals of this study were to determine if terrestrial LiDAR (TLS) can be used as an effective tool to improve local allometric equations and what are the implications of fusing these equations to airborne LiDAR data sources for biomass and carbon estimation. Our non-destructively determined allometric relationships were strong with lower error than the national-scale equations (R²= 0.98, RMSE = 125 kg) using a low sample size (n= 24). National allometric equations overestimated biomass in the species studied and total site-wide biomass significantly decreased by over 35 Mg/ha when our equations were used. The proposed pipeline has the potential to significantly reduce labor costs associated with destructive sampling and simplify the process of detailed C monitoring, while improving the quality and quantity of data retrieved.
Author affiliations: Department of Environmental Sciences, University of Virginia

Chemotaxis – a phenomenon in which pollutant degrading bacteria have the ability to detect chemical concentration gradients – can augment the transfer of bacteria to sites of contamination in polluted aquifers, thereby leading to enhancement in contaminant biodegradation. This study aimed to investigate the transport of chemotactic bacteria in response to distributed sources of contaminant within porous media. A fully saturated continuous-flow sand-packed column system containing uniformly distributed naphthalene crystals was utilized to simulate a polluted subsurface environment. At initial time, a 10 mL pulse of a mixture of Pseudomonas putida G7, which is chemotactic to naphthalene, and Pseudomonas putida G7 Y1, a non-chemotactic mutant strain, was introduced into the sand column at equal concentrations. Bacterial effluent concentrations were measured with time, and the resulting breakthrough curves were used to quantify bacterial transport parameters. Control experiments without naphthalene in the sand column were also conducted. In the presence of naphthalene, longitudinal dispersion of PpG7 increased by a factor of 3 and percent recovery decreased by 43%. Transport of PpG7 Y1 was not affected by the chemoattractant, as expected. The results imply that chemotaxis may lead to a greater retention of bacteria at the site of contamination. In addition, a modified advection-dispersion equation, containing a chemotactic velocity term, was used to mathematically predict chemotactic bacterial transport in polluted subsurface environments similar to that of the lab-scale sand column system. A good correlation was observed between experimental and computational results, suggesting that the modified conservation equation can adequately predict chemotaxis-induced bacterial transport in homogeneous and fully saturated aquifers with localized contaminant gradients. Chemotaxis may work to improve aquifer biorestoration by augmenting the retention of bacteria at the site of pollution.

Bumblebees, economically and ecologically important pollinators, have been experiencing wide-spread declines. Assessing bumblebee communities for changes in population size, diversity, and robustness is complicated by cryptic nesting and wide foraging ranges. Few studies have sought to assess bee communities by examining their interactions with higher trophic levels. Parasite/parasitoid abundance may serve as a biological indicator for host community health; this may particularly be the case with parasitoids, since parasitoids are lethal to their hosts, while parasites by necessity keep hosts alive. Robust host communities are required to support robust parasitoid communities, especially when host and parasitoid have similar generation times and/or use similar resources. For preliminary exploration of this approach, sites were located near roadsides or in restored meadows in Northern Virginia where landscape factors differed in degree of human development. Rates of parasitism by parasitoid flies (genus Physocephala) were assessed for one species of bumble bee (Bombus impatiens) present at all sites through fixed sample size collection in each location. These rates were compared between site types, with a prediction that parasitism should be higher in restored meadow sites due to favorable habitat for bumble bee nesting and foraging, and for parasitoid foraging and overwintering. Great variation in rates of parasitism were found among sites in both roadsides and meadows, suggesting further investigation is needed to determine the cause of this variation and the practicality of this approach.
Author affiliations: Department of Environmental Sciences, University of Virginia

Sudden unexpected changes, or shocks, can alter the function or state of a system. A system’s ability to respond and adapt to a shock is a measure of the system’s resilience. When shocks occur in food systems they can impact local nutrition and employment. Even when food production shortages are temporary, periods lacking essential nutrients can adversely impact the health of vulnerable populations such as pregnant women, children, and the ill. Further, shocks to primary commodities may have distant impacts on food prices and access via propagation through the global trade network. While shocks have been defined and identified in specific systems with known causes, these methods cannot be applied in general when the shock cause is unknown. This is problematic for food production systems, including fisheries, which are exposed to multiple environmental, policy, and economic shocks. One approach to identify shocks is to use expert or local knowledge to identify events that they consider as a shock to a system. While this approach is valuable for studying individual systems, it is difficult to standardize the meaning of a shock across systems and may be biased against shocks that are not widely reported on or those which occurred in distant memory. As a result, a data-driven approach can complement system knowledge to identify shocks across systems. Here we apply a statistical shock identification approach to identify shocks in fisheries catch time series in order to ask the following questions: 1) have the frequency or intensity of shocks increased; 2) do regions or/and production systems have more, larger or longer shocks; and 3) how are shocks divided among decreased exports, increased imports, and changes in domestic supply? Preliminary results and case studies of shocks to fishery systems will be presented.
Author affiliations: Department of Environmental Sciences, University of Virginia

Genetic diversity replaces the functional role of species diversity in seagrass beds and directly increases the resilience of these ecosystems to intense disturbance. However, many populations at the periphery of a species range, where climate change is likely to drive range shifts, display decreased genetic diversity compared to their centrally located counterparts. In order to assess the genetic population structure of the tropical seagrass Halodule wrightii, over 500 samples were collected from Florida, North Carolina, and Bermuda locations. Allelic diversity, inbreeding, and population differentiation were compared across populations using 6 microsatellite loci. Inbreeding fixation values indicate that North Carolina and Bermuda populations are outbreeding. Populations among Florida, North Carolina, and Bermuda sites were highly differentiated, indicating a lack of large-scale gene flow between populations. Understanding the basic reproductive processes of H. wrightii will be important for assessing population stability, in particular for the expanding populations along the coast of North Carolina.
Author affiliations: Department of Environmental Sciences, University of Virginia

In the Afro¬Brazilian martial art, capoeira, the act of fighting is always referred to as ‘jogar’ or ‘playing.’ Indicative of the inherently subversive qualities of both the practice and resultant philosophy, the aim of the players is to create a rhythm or dialogue with their opponents. Players win, not by blocking or dominating their competitor, but through mimicry, inversion and trickery. Since its roots in colonial Brazil, capoeira has remained a living, breathing and sweating historical artifact, however in the last few decades, the practice has been adopted and adapted worldwide within urban centers. Innately performative, the rodas, or ‘playing circles,’ usually occur outdoors and within public areas. Therefore, the practice focuses not only on the player’s interactions with each other, but also their engagement with the spatial conditions of the surrounding environment. By temporarily finding and filling public areas, both physically and aurally, capoeiristas are demonstrating new and dynamic uses for outmoded or overlooked spaces of the modern city, as well as peacefully asserting their identity and right to control city space.
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.

Tropical peat forests are an important global terrestrial carbon sink. The total size of the global tropical peatland soil carbon pool is estimated at 88.6 Pg C (Page et al. 2011) compared to 247 Pg of C stored in tropical forest biomass across Africa, America, and Asia (Saatchi et al. 2011). In Indonesia, peatlands are a major and growing source of greenhouse gas (GHG) emissions due to increasing pressure from the expansion of oil palm and pulp wood plantations. Peat drainage generates long-term CO₂ emissions from the decomposition of soil organic material over time. To investigate relationships among land use, climate, and peat carbon storage we collected monthly data on soil CO₂ fluxes and environmental parameters in oil palm plantations on peat and in mature peat swamp forests in Central Kalimantan, on the southern coast of Indonesian Borneo. Sampling through time over variable climatic conditions allows for a robust site-specific characterization of the interaction between climate drivers and direct biogeophysical controls on trace gas fluxes from peat. We compare soil CO₂ fluxes from oil palm and forest on peat during the 2015 El Nino with measurements collected from Jan 2014 to Jun 2015 to characterize the response of peatland CO₂ emissions to an extreme climate event.
Author affiliations: Department of Environmental Sciences, University of Virginia

Carbon, nitrogen, and water are important elements of UVA’s environmental impact. In 2011, the UVA Board of Visitors passed a carbon footprint reduction goal, which commits the University to reduce its footprint 25% by 2025. In 2013, the BOV updated this to include a matching nitrogen footprint reduction goal. The University also has a direct water reduction goal in place and is considering incorporating a virtual water component. Food production and consumption directly affect all three environmental issues. Students should better understand the impact of their food consumption patterns and take action to reduce it. November 9-24, 2015, food items in the Clark Cafe were labeled with a “sustainability rating” (1-5) that reflected the amount of carbon, nitrogen, and water used in the production of the labeled item. Virtual carbon, nitrogen, and water factors from published sources were applied to get total “footprints” for each product. The 1-5 ratings were assigned to each product for carbon, nitrogen, and water, and then products were given an overall rating (1-5), equally weighting the impact of carbon, nitrogen, and water. Preliminary analyses comparing consumers’ purchase patterns during the study weeks to the two weeks before and after show that labels had a positive effect. Given the success of this study, similar labeling projects will be repeated and expanded at Clark and other UVA dining locations.

Salt marsh pink (Kosteletzkya pentacarpos (L.) Ledebour (Malvaceae)) is found in brackish marshes along the Atlantic and Gulf Coasts of the United States. K. pentacarpos is a perennial, non-clonal, herbaceous halophyte that has been proposed as a crop plant in low-elevation agricultural fields experiencing salinization. These, and other, characteristics of this plant make it a promising species for facilitating high marsh development in agricultural fields that have been abandoned due to sea level rise. In 2014, we examined establishment of locally collected K. pentacarpos seeds and seedlings in an abandoned agricultural field where soybeans were grown as recently as 7 years ago. Half the plots contained a few stems of Spartina patens and Distichlis spicata and half did not. K. pentacarpos seeds and seedlings were planted with as little disturbance to the existing plant communities as possible; control plots were not planted. K. pentacarpos seed germination, seedling survival, and plant height and seed production were measured during the summer and fall. Other measures included, plant community composition focused on changes in abundance of S. patens and D. spicata, groundwater levels, and soil moisture in plots planted with K. pentacarpos and in unplanted plots. Mallow became well established in plots where seeds were broadcast over the soil rather than drilled into the soil. Transplanted seedlings survived for less than one month. Plant community composition appeared unchanged in mallow plots except that mallow became part of the community. Thus, after one year it is not clear if K. pentacarpos facilitates conversion of old field plant communities to high salt marsh communities.