Contribution of motor vehicle emissions to organic carbon and fine particle mass in Pittsburgh, Pennsylvania: Effects of varying source profiles and seasonal trends in ambient marker concentrations

We present estimates of the vehicular contribution to ambient organic carbon (OC) and fine particle mass (PM) in Pittsburgh, PA using the chemical mass balance (CMB) model and a large dataset of ambient molecular marker concentrations. Source profiles for CMB analysis are selected using a method of comparing the ambient ratios of marker species with published profiles for gasoline and diesel vehicle emissions. The ambient wintertime data cluster on a hopanes/EC ratio–ratio plot, and therefore can be explained by a large number of different source profile combinations. In contrast, the widely varying summer ambient ratios can be explained by a more limited number of source profile combinations. We present results for a number of different CMB scenarios, all of which perform well on the different statistical tests used to establish the quality of a CMB solution. The results illustrate how CMB estimates depend critically on the marker-to-OC and marker-to-PM ratios of the source profiles. The vehicular contribution in the winter is bounded between 13% and 20% of the ambient OC (274±56–416±72 ng-C m⁻³). However, variability in the diesel profiles creates uncertainty in the gasoline–diesel split. On an OC basis, one set of scenarios suggests gasoline dominance, while a second set indicates a more even split. On a PM basis, all solutions indicate a diesel-dominated split. The summer CMB solutions do not present a consistent picture given the seasonal shift and wide variation in the ambient hopanes-to-EC ratios relative to the source profiles. If one set of source profiles is applied to the entire dataset, gasoline vehicles dominate vehicular OC in the winter but diesel dominates in the summer. The seasonal pattern in the ambient hopanes-to-EC ratios may be caused by photochemical decay of hopanes in the summer or by seasonal changes in vehicle emission profiles.     

Transport of cadmium and other metals in the blood of the bivalve mollusc Mercenaria mercenaria

The distribution of metals (Ba, Cr, Cu, Fe, Mn, Ni and Zn) in the blood plasma and the circulating hemocytes was determined for a eulamellibranch bivalve, the quahog Mercenaria mercenaria (L.), collected from a relatively clean site at Falmouth, Massachusetts, USA. Whole blood volume was an exponential function of quahog length (Y=5.71×10^-5 X^3.0678; Y=ml of whole blood; X=mm length). Of this volume, 1.2±0.3% ( ) was attributable to blood cells. Total metal content (g metal, or g metal normalized per g of whole blood) was much higher in blood plasma than in hemocytes. In quahogs exposed in the laboratory to 100 ppb ¹⁰⁹Cd, 93.0% of the total accumulated blood Cd was in the plasma rather than in the circulating hemocytes (7.0%), irrespective of the length of exposure (1 h to 31 d). Less than 5% of the plasma Cd was either Cd²⁺, small inorganic Cd complexes or bound to organic molecules with a molecular weight smaller than 1 000. Cadmium was primarily bound to high molecular weight protein(s) (>60 000 daltons) within the plasma. This plasma protein-Cd complex has a low affinity constant (approximately 10⁴ M ^-1), indicating non-specific Cd binding, although the capacity for Cd-binding in the plasma is great (as high as 200 g Cd per ml of plasma). Blood plasma may be far more important in metal transport than has previously been realized.     

The use of the oyster Saccostrea glomerata as a biomonitor of trace metal contamination: intra-sample, local scale and temporal variability and its implications for biomonitoring

Cu, Cd, Zn, Pb and Se concentrations were measured in the bivalve mollusc Saccostrea glomerata(Iredale and Roughly) from two uncontaminated locations, Clyde River Estuary, Batemans Bay and Moona Moona Creek, Jervis Bay, to determine natural variability of metals associated with mass, gender, age, tissue type and site within location. Trace metals were also measured in the Clyde River Estuary over an 11 year period and in five other NSW estuaries (Hastings River, Hunter River, Georges River, Tillgerry Creek and Lake Pambula) over a 13-month period to determine temporal variability and if diploid and triploid oysters accumulate trace metals differently. There were few significant relationships between trace metal concentrations and mass and no significant differences in trace metal concentrations between female and male oysters. Younger oysters (1.3 years) had significantly higher copper concentrations and higher trace metal variability than mature oysters (3 years). Different tissues have different trace metal concentrations with muscle tissues having lower concentrations. Considerable inherent variability occurs in oyster cohorts. Analysing specific tissues did not reduce variability of trace metal concentrations. Comparison of trace metal concentrations at two sites within the Clyde Estuary showed a significant difference in zinc concentrations. Cu, Cd, Zn and Se concentrations were generally higher and less variable in triploids than diploids. Pb had a variable pattern of accumulation with no consistent elevation in diploids or triploids. Inter annual variability of trace metal concentrations was considerable and trace metal concentrations also fluctuated throughout an annual cycle with no clear seasonal trends. Measurement of trace metals at known contaminated locations showed that Saccostrea glomerata accumulates metals in response to contamination. Saccostrea glomerata meet most of the requirements to be a biomonitor of trace metal contamination as they are abundant, sessile/sedentary, easy to identify, provide sufficient tissue for analysis, and accumulate trace metals in response to contamination. However, as trace metal concentrations can vary with mass, age, estuary position, ploidy type and temporally, care must be taken to collect individual organisms of similar mass, age and ploidy type to minimise variability, and from similar consistent positions and times to allow for seasonal changes in environmental conditions. Trace metal concentration variability is higher in young animals, thus to reduce variability, older mature animals could be selected. However, with immature oysters there are no complications because of the effects of spawning i.e. sudden loss of trace metals or body mass.     

Sustaining local values through river basin governance: community-based initiatives in Australia's Murray–Darling basin

Australia's Murray–Darling basin (MDB) water plan is an ambitious attempt to balance ecological, social and economic benefits, where a key aspect of the reform process has been recovery of water for environmental use. This paper focuses on a set of initiatives established by a local non-governmental organisation and an Indigenous community designed to engage with local values and priorities and incorporate them into this complex river basin governance system. Contrary to expectations that local and basin-scale interests and outcomes will diverge, the case studies reveal the ability for local groups to collaboratively manage both land and water resources to achieve locally important outcomes, and contribute to basin-scale outcomes. The analysis also highlights a progressive style of community-based environmental management for water management that utilises multiple institutional arrangements and planning pathways to protect the values that are important to local communities, and to nest those values within the broader effort to sustainably manage the basin's water resources.     

Meeting the climate change challenge: a scan of greenhouse gas emissions in BC communities

The Canadian province of British Columbia (BC) is taking significant steps towards climate change mitigation, including a carbon tax on fossil fuels and legislation that mandates greenhouse gas (GHG) reductions within public sector organisations and GHG reduction targets for municipalities. This paper carries out a preliminary scan of the GHG emissions of BC communities using the provincially mandated Community Energy and Emissions Inventory reports. We map trends in energy consumption and emissions per capita while uncovering correlations between these variables and land-use planning, geographic, and demographic variables. These data have shown that: (1) energy consumption in BC is an adequate proxy for GHG emissions; (2) transportation, more than buildings, is a strong driver of overall GHG emissions; (3) building emissions are not likely to be strongly influenced by dwelling type, but density of buildings is crucial; (4) geographic location influences emissions; and (5) population size and age do not appear to influence per capita emissions. These findings are particularly important as they suggest that the potentially intransigent factors of income and population size need not be barriers to achieving significant GHG reductions. The policy onus thus falls squarely on transportation planning, land-use, energy conservation, and fuel switching. This in turn highlights the importance of deeper underlying sociocultural and political preferences, which shape the behaviours that have a strong bearing on emissions profiles.     

Coastal construction trends in response to coastal erosion: an opportunity for adaptation

In Florida, more than half of the state’s sandy beach coastlines are designated as critical erosion areas by the Florida Department of Environmental Protection (FDEP 2008). At the same time, the economic contribution of coastal construction is being confounded by the fiscal peril facing Florida (Bird in Ann Geomorph 57:1–9, 1985, Pew Center on the States 2009, U.S BEA 2009). It is therefore an opportune time for an evaluation of coastal erosion policy response which specifically addresses coastal construction. Furthermore in Florida, an increasing coastal population requiring the provision of structural development necessitates an improved understanding of how legislative intent which avoids the cumulative impacts of development is translated through quantified policy response. This study characterizes how coastal development trends in Florida have responded to critical erosion designation. Using spatial and temporal analysis of coastal construction permitting data from 1987 to 2007, three coastal counties in northwest Florida were selected for this study. This selection was based on proximity to the designated ecologically sensitive Apalachicola National Estuarine Research Reserve (ANERR). This study has indicated that clusters of development have not been reduced or redirected by critical erosion designation in certain areas of the study counties. Therefore this study has implications for the regulatory framework governing coastal development permitting in Florida, which is of timely relevance for sea-level rise adaptation.     

Common and Conflicting Interests in the Engagements between Conservation Organizations and Corporations

The conservation community increasingly views the corporate sector as a positive force for conservation. Collaborations between corporations and nongovernmental conservation organizations (NGOs) seek to mitigate the negative effects of corporate activities and augment positive conservation outcomes. I reviewed the establishment of corporate social responsibility (CSR) policies by corporations; the emerging focus on environmental practices and sustainability; and the history of engagement between corporations and nongovernmental organizations. I considered the ethical and reputation vulnerabilities of these collaborations, which depend especially on the financial nature of the relationship and reviewed how CSR approaches have influenced corporate practices. I concluded that whereas CSR practices can act to mitigate negative environmental impact, to date they have had limited positive effect on biodiversity conservation. Intereses Comunes y Conflictivos en los Compromisos entre Organizaciones y Corporaciones de Conservación     

Concentrations of Particulate Matter Emitted from Large Cattle Feedlots in Kansas

Effective August 1, 1978 the Government of Canada ordered that all future federal regulations of significant economic import, covering the subjects of health, safety and fairness be preceded by the publication of a formal socioeconomic impact analysis (SEIA). Environmental protection regulations are included. I encountered my first public reaction to this announcement at a conference in Ottawa on the subject of “Jobs and the Environment”. A union official duly observed that the SEIA was obviously industry’s answer to having to carry out Environmental Impact Assessments. Not much later, I was told by a senior environmental official of an overseas country that what SEIA really did was to place the burden of proof on governments as to the need for control, rather than leaving industry to show that their activities were not damaging to the environment.     

Enhanced aerobic bioremediation of a gasohol release in a fractured bedrock aquifer

In January 2005, a gasoline tanker carrying approximately 8,500 gallons of gasohol (gasoline containing 10 percent ethanol) overturned and caught fire in the front yard of a residence. Emergency response crews responded to the accident, extinguished the fire, and recovered residual gasoline on the ground surface. Soil impacted by the release was then removed and disposed of off‐site and free‐phase gasohol was recovered using a combination of vacuum recovery, pumping, and bailing to the extent practicable. Following free product recovery efforts, a feasibility evaluation was completed to select a technology to address the remaining dissolved‐phase contaminants that resulted in biosparging pilot testing and, ultimately, the installation of a full‐scale biosparging system. The full‐scale system has been operating for approximately 21 months, and contaminant concentrations within the heart of the plume have decreased dramatically over a short period of time—in most cases, to below applicable cleanup standards. Despite the complex hydrogeologic conditions and significant initial concentrations, biosparging has proven to be an effective technology to remediate this gasohol release, and it is anticipated that drinking‐water standards can be achieved following two to three years of biosparging (i.e., an additional 3 to 15 months of operations). © 2010 Wiley Periodicals, Inc.