Humane slaughter of poultry: The case against the use of electrical stunning devices

Is the use of electrical stunners adequately discharging our moral obligations with respect to the humane slaughter of poultry? Below, three separate lines of investigation show that we cannot give an unequivocal answer to this question. First, five potentially humane methods of poultry slaughter are examined. Electrical stunning is found to be an acceptable method of rendering birds unconscious before slaughter. However, we lack sufficient evidence to claim that it is the most humane method currently available. Second, surveys of poultry processing plants show that, with alarming frequency, a proper stun is not achieved. An investigation of the complexity of the electrical stun process shows the difficulties involved and suggests that under many on-the-floor slaughterhouse conditions, consistently proper stunning is likely to remain unachievable. Finally, the call to overcome inconsistent stun results by increasing current flow to levels that electrocute birds is investigated. Controversy surrounding the impact of electrocution on carcass quality and operator safety will continue to cause resistance to the adoption of this method of poultry slaughter. The conclusion offers four recommendations that follow from the cumulative results of these investigations.     

Potential for carbon sequestration in Canadian forests and agroecosystems

The potential for carbon (C) sequestration was examined in selectedCanadian forest settings and prairie agroecosystems under severalmanagement scenarios. A simple C budget model was developed toquantitatively examine C sequestration potential in living biomass of forestecosystems, in associated forest-product C pools, and in displaced fossil-fuelC. A review of previous studies was conducted to examine C sequestrationpotential in prairie agroecosystems. In the forest settings examined, ourwork suggests that substantial C sequestration opportunities can be realizedin the short term through the establishment of protected forest-C reserves.Where stands can be effectively protected from natural disturbance, peaklevels of biomass C storage can exceed that under alternative managementstrategies for 200 years or more. In settings where it is not feasible tomaintain protected forest-C reserves, C sequestration opportunities can berealized through maximum sustained yield management with harvestedbiomass put towards the displacement of fossil fuels. Because there is afinite capacity for C storage in protected forest-C reserves, harvesting forestbiomass and using it to displace the use of fossil fuels, either directlythrough the production of biofuels or indirectly through the production oflong-lived forest products that displace the use of energy-intensive materialssuch as steel or concrete, can provide the greatest opportunity to mitigategreenhouse gas emissions in the long term. In Canadian prairieagroecosystems, modest C sequestration can be realized while enhancingsoil fertility and improving the efficiency of crop production. This can bedone in situations where soil organic C can be enhanced without relianceupon ongoing inputs of nitrogen fertilizer, or where the use of fossil fuelsin agriculture can be reduced. More substantial C offsets can be generatedthrough the production of dedicated energy crops to displace the use offossil fuels. Where afforestation or reconstruction of native prairieecosystems on previously cultivated land is possible, this represents thegreatest opportunity to sequester C on a per unit-area basis. However,these last two strategies involve the removal of land from crop production,and so they are not applicable on as wide a scale as some other Csequestration options which only involve modifications to currentagricultural practices.     

Comparative analysis of air pollution emissions by electric utilities: Public policy implications

One of the objectives of US environmental regulations was to reduce industrial air pollution emissions, especially from the electric utility industry, the major industrial air polluter. In this study, a comparative analysis of air pollution emissions from fossil-fuel-burning electric utility plants is conducted. The analysis focuses on a 12-yr period from 1975 to 1987 for three air pollutants: particulates, surfur dioxide, and nitrogen oxides. The results indicate that particulate emissions have been significantly reduced but that sulfur dioxide and nitrogen oxides are still major problems for a number of plants. Furthermore, the disparity in the performance by plants indicates that by using current technology, the industry as a whole could greatly reduce these emissions. These results have policy implication for future environmental legislation.     

Impact of government regulations on pollution performance of pulp and paper firms

A comparative study of water pollution emissions of pulp and paper companies for the period 1978–1983 indicates a reduction in emissions for most firms. This improvement in pollution performance is attributed to the federal government's water pollution policy. Although there is an overall decline in water pollution, some firms have actually increased their emissions. Furthermore, there is still a wide disparity in each company's performance, although the differences are narrowing.     

The use of rice crop residues as a non-commercial energy source in the developing world: The energy and environmental implications

The potential biomass energy that can be derived from the harvest of rice crop residues is calculated for three methods of crop production. The potential energy available amounts to 3.70 × 10¹⁰ J ha^?1 year^?1 for traditional methods, 7.93 × 10¹⁰ J for the labor-intensive and 8.36 × 10¹⁰ J for the capital-intensive methods. The net energy benefits available for cooking, heating and biogasification are calculated on a per hectare basis taking into account the costs of collection, transportation and processing. The amounts of energy available for cooking and heating range from 3.70 × 10⁹ to 8.33 × 10⁹ J ha^?1, and the amounts of energy for methanol use range from 1.85 × 10⁹ to 4.17 × 10⁹ J ha^?1 year^?1.The ecological problems associated with soil erosion, nutrient loss and pesticide use are evaluated in terms of the compensatory energy costs involved, and the resultant net energy balance for each method of rice production is calculated. The net energy available per hectare for the traditional method is 3.43 × 10¹⁰ J, for the labor-intensive method, 7.25 × 10¹⁰ J and for the capital-intensive method, 7.02 × 10¹⁰ J. The harvest of rice crop residues in the developing world could provide up to 5.80 × 10¹⁸ J year^?1.The use of rice crop residues is investigated within the context of the rural village energy system. The prospects for the use of rice crop residues are evaluated in relation to alternative energy sources and it is concluded that regional residue harvest programs should be implemented cautiously, integrating soil management and environmental planning procedures where appropriate.     

Implications of Atmospheric Change for Biodiversity of Aquatic Ecosystems in Canada

Overall, the greatest threats to Canadian and global biodiversity are associated with conversions of natural ecosystems to anthropogenic ones, and over-exploitation of biological resources. This circumstance does not, however, trivialize the importance of atmospheric influences. Although scientific understanding of the risks is incomplete, it is nevertheless clear that anthropogenic changes in atmospheric stressors are potentially damaging to biodiversity and other ecological values over medium- and longer-term scales. It is important that greater investments be made in support of longer-term monitoring and research designed to understand the effects of atmospheric and other environmental stressors on the biodiversity and structure and function of Canadian ecosystems.