Long-term monitoring of a marine geologic hydrocarbon source by a coastal air pollution station in Southern California

Hourly total hydrocarbon (THC) data, spanning 1990–2008 from a California air pollution station located near the Coal Oil Point (COP) seep field, were analyzed and clearly showed geologic CH₄ emissions as the dominant local source. Annual COP emissions are conservatively estimated as 0.015 Tg CH₄ year^?1 and represent a natural and concentrated geologic methane source (24 m³ m^?2 day^?1 gas flux at some active seeps, Clark et al., 2010). For a sense of the scale and potential importance to the regional Southern California methane budget, COP emits an amount equivalent to 8% of the estimated Los Angeles County anthropogenic emissions. Station THC measurements near COP showed a strong wind dependency with elevated levels closely correlated with a sonar-derived spatial distribution of seep field emissions. THC varied seasonally, with a maximum in January and minimum in July and a peak-to-peak amplitude of 0.24 ppm. The seasonal signal was more readily apparent midday (R² = 0.69 harmonic fit), compared to nighttime and morning (R² < 0.45). The bimodal diel THC pattern consisted of seasonally-modulated peaks in the morning and evening.THC temporal and spatial trends were consistent with both transport and source emission variations. Long-term, annual seep field emissions consistently decreased on a field-wide basis until the late 1990s, before increasing consistently, most likely as a function of underlying geologic processes. This study demonstrates the value of municipal air quality monitoring stations for insight into local greenhouse gas sources and highlights the non-negligible and variable contribution from marine geologic seepage.     

Green roofs as a means of pollution abatement

Green roofs involve growing vegetation on rooftops and are one tool that can help mitigate the negative effects of pollution. This review encompasses published research to date on how green roofs can help mitigate pollution, how green roof materials influence the magnitude of these benefits, and suggests future research directions. The discussion concentrates on how green roofs influence air pollution, carbon dioxide emissions, carbon sequestration, longevity of roofing membranes that result in fewer roofing materials in landfills, water quality of stormwater runoff, and noise pollution. Suggestions for future directions for research include plant selection, development of improved growing substrates, urban rooftop agriculture, water quality of runoff, supplemental irrigation, the use of grey water, air pollution, carbon sequestration, effects on human health, combining green roofs with complementary related technologies, and economics and policy issues.     

Estimating carbon in savanna ecosystems: rational distribution of effort

Minimising the cost of repeatedly estimating C (C) stocks is crucial to the financial viability of projects that seek to sell C credits. Depending on the price of C, this may imply less or more sampling effort than would be applied for science objectives. In systems with heterogeneous C pools, such as savannas, this translates into a variable-effort sampling strategy that maximises the marginal additional C that can be claimed per incremental unit of effort expended. Analysis of a savanna in north-eastern South Africa indicates relatively modest returns per hectare due to the small C quantities and low sequestration rates. Under these conditions, areas in excess of 1,000 ha and infrequent sampling frequencies of 5–10 years are required to make such projects financially viable. For such projects the sample variance, number of samples, cost per sample and establishment costs have negligible impacts on financial viability. It was also found that the soil-C pool contributes up to three times the net returns of the aboveground C pool and provides a strong argument to monitor soil C for certification and market trading. The financial viability estimates, however, do not include the management or opportunity costs incurred in changing the land use. The economies of scale identified in this study combined with the massive area covered by savannas indicate that these additional costs can be covered. Further research is recommended to quantify these costs and interrogate the feasibility of large scale (in excess of 10,000 ha) C-sink projects in savanna systems.     

A free-enzyme catalyst for the bioremediation of environmental atrazine contamination

Herbicide contamination from agriculture is a major issue worldwide, and has been identified as a threat to freshwater and marine environments in the Great Barrier Reef World Heritage Area in Australia. The triazine herbicides are of particular concern because of potential adverse effects, both on photosynthetic organisms and upon vertebrate development. To date a number of bioremediation strategies have been proposed for triazine herbicides, but are unlikely to be implemented due to their reliance upon the release of genetically modified organisms. We propose an alternative strategy using a free-enzyme bioremediant, which is unconstrained by the issues surrounding the use of live organisms. Here we report an initial field trial with an enzyme-based product, demonstrating that the technology is technically capable of remediating water bodies contaminated with the most common triazine herbicide, atrazine.     

Legitimacy &; Canadian Farm Animal Welfare Standards Development: The Case of the National Farm Animal Care Council

Awareness of farm animal welfare issues is growing in Canada, as part of a larger food movement. The baseline Canadian standards for farm animal welfare—the Recommended Codes of Practice for the Care and Handling of Farm Animals—are up for revision. The success of these standards will depend in part on perceived legitimacy, which helps determine whether voluntary code systems are adopted, implemented, and accepted by target audiences. In the context of the Codes, legitimacy will also hinge on whether the standards-developers marshal narratives about farm animals that accord with their audiences’ expectations. The aim of this paper is to catalogue factors that influence legitimacy in farm animal welfare standard-setting, including which narratives of animal welfare are emphasized by standard-setters. Drawing upon the example of the baseline Canadian standards, and the National Farm Animal Care Council, the paper will present a theoretical and methodological framework for analyzing legitimacy in the context of animal welfare standards-development and discuss associated policy considerations.     

ESTIMATED RUNOFF FROM MAN-MADE SNOW1

ABSTRACT: The consumptive loss from man-made snowmaking at six Colorado ski areas is calculated. The focus of the procedures in this investigation is on the consumptive loss that occurs to man-made snow particles during the period they reside on or in the snowpack until spring snowmelt (termed the watershed loss). Calculated watershed losses under a variety of precipitation and temperature conditions at six ski areas varied from 7 to 33 percent. These calculations were made using the calibrated Subalpine Water Balance Simulation Model (Leaf and Brink, 1973a, 1973b). The watershed loss of 7 to 33 percent indicates the range of likely watershed losses that can be expected at Colorado ski areas. A previous paper by the authors (Eisel et al., 1988) provided estimates of the mean consumptive loss during the snowmaking process (termed initial loss) for conditions existing at Colorado ski areas to be 6 percent of water applied. Therefore, based on the mean initial loss, the total consumptive loss from man-made snowmaking under conditions found at Colorado ski areas could be expected to range from 13 to 37 percent. These results demonstrate the range of total consumptive losses that could be expected in various years and for various watershed conditions. These total percentage losses cannot be extrapolated directly to other specific sites because the total consumptive loss is dependent on temperature during actual snowmaking, temperature and precipitation throughout the winter at the specific ski area, and watershed conditions at the ski area. Consumptive losses to man-made snow for a specific ski area should be estimated using the handbook procedures developed especially for this purpose (Colorado Ski Country USA, 1986b).     

Reductive dehalogenation: A subsurface bioremediation process

Introduction and large-scale production of synthetic halogenated organic chemicals over the last fifty years has resulted in a group of contaminants that tend to persist in the environment and resist both biotic and abiotic degradation. The low solubility of these types of contaminants, along with their toxicity and tendency to accumulate in food chains, make them particularly relevant targets for remediation activities. Among the mechanisms that result in dehalogenation of some classes of organic contaminants are stimulation of metabolic sequences through introduction of electron donor and acceptor combinations; addition of nutrients to meet the needs of dehalogenating microorganisms; possible use of engineered microorganisms; and use of enzyme systems capable of catalyzing reductive dehalogenation. The current state of research and development in the area of reductive dehalogenation is discussed along with possible technological application of relevant processes and mechanisms to remediation of soil and groundwater contaminated with chlorinated organics. In addition, an overview of research needs is suggested, which might be of interest for development of in-situ systems to reduce the mass of halogenated organic contaminants in soil and groundwater.     

Fostering sustainable small-scale investments: lessons from experience and ideas for intervention and innovation

This article presents lessons from experience pertinent to implementing small-scale natural resource and related investment projects in developing countries. It outlines ideas for intervention and innovation to foster such investments. Particular emphasis is placed on private-sector participation in these investments. Following a brief presentation of the economic development and other arguments that support intervention and innovation in support of such small-scale natural resource investments, the article discusses many of the lessons learned from experience. These lessons reinforce those touched upon in the investment-specific discussions in the previous articles. The experience and associated lessons that are examined include experiences in both developing and developed countries and encompass not just lessons from natural resource investments, but also small-scale investments in other sectors. Financing and other innovations which facilitate meeting the challenges are drawn from relevant experience where barriers to investment have been surmounted. Options for programme and project interventions to increase market penetration of small-scale investments and achieve the associated development linkages and synergies are suggested. These suggestions are aimed especially at governments and bilateral and multilateral development finance and development assistance entities. It is those players who might support such interventions in collaboration with local financial institutions and other market players.