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151.
Strategies to involve agribusiness in the development of sustainable agricultural systems have been limited by the lack of a comprehensive conceptual framework for identifying the most critical supportive policies, programs and regulations. In this paper, we propose an efficiency/substitution/redesign framework to categorize strategies for modifying agribusiness practices. This framework is then used to identify a diverse range of short, medium, and long-term strategies to be pursued by governments, community groups, academics and agribusiness to support the transition. Strategies discussed include corporate greening, ethical investment, changing the legal status of the corporaton, new business forms and the development of ecological economics.  相似文献   
152.
ABSTRACT. As demands upon available water supplies increase, there is an accompanying increase in the need to assess the downstream consequences resulting from changes at specific locations within a hydrologic system. The problem is approached in this study by hybrid computer simulation of the hydrologic system. Modeling concepts are based upon the development of basic relationships which describe the various hydrologic processes. Within a system these relationships are linked by the continuity-of-mass principle. Spatial resolution is achieved by considering the modeled areas as a series of subbasins. The time increment adopted for the model is one month, so that time varying quantities are expressed in terms of mean monthly values. The model is general in nature and is applied to a particular hydrologic system through a programmed verification procedure whereby model coefficients are evaluated for the particular system. In this study the model is applied to the Bear River basin of western Wyoming, southern Idaho, and northern Utah. Comparisons between observed and computed outflow hydrographs show good agreement. The utility of the model is demonstrated by predicting the effects of various possible water resource management alternatives. The verified hybrid computer program can be digitized for application to the digital computer.  相似文献   
153.
The sustainable management of coastal natural resources inevitably involves identifying stakeholder conflicts and developing planning processes that prevent these conflicts from becoming intractable disputes. This study links environmental conflict to specific areas within a large ecological system. Specifically, we use Geographic Information Systems (GIS) to map potentially competing stakeholder values associated with establishing protected areas in Matagorda Bay, Texas. By overlaying multiple values associated with a range of stakeholders across space, we are able to identify hotspots of potential conflict as well as areas of opportunity for maximizing joint gains. Mapping stakeholder conflict is an approach to proactively locate potential controversy in response to a specific environmental management proposal and guide decision makers in crafting planning processes that mitigate the possibility of intractable disputes and facilitate the implementation of sustainable coastal policies. Results indicate that under different management scenarios, protected area proposals will generate more conflict in specific areas. Most notably, regulated uses would produce the greatest degree of conflict on or near shore, particularly at the mouth of the Colorado River. Additionally, of all the management scenarios evaluated, the prohibition of coastal structural development would generate the overall highest level of conflict within the Bay. Based on the results, we discuss the policy implications for environmental managers and provide guidance for future research on location-based conflict management within the coastal margin.  相似文献   
154.
Regionally specific sustainability processes that account for diverse environments and populations and that integrate social, economic, political and ecological spheres are being developed in Western Australia. A coordinated commitment to sustainability principles and a participatory philosophy by the state and local governments is necessary. This requires a transformation of the public service, from a director of passive programmes and laws to a facilitator of community projects and outcomes, towards an enabling state. An international participatory paradigm provides an array of concepts and methods for local and regional communities in partnership with government and industry to achieve this. Participatory methodologies are utilised successfully around the globe to create an institutional framework that facilitates a process of dialogue, partnership, networking, learning and managing change. This paper examines the potential contribution of a participatory approach to improve the participatory capacity of regional communities and both local and state governments towards the facilitation of regional sustainability processes.  相似文献   
155.
California and other regions in the United States are becoming more populated and ethnically diverse, and thus, ecological impacts on the wildland–urban interface are a significant policy concern. In a socioeconomic assessment focused on the geographic regions surrounding four national forests in southern California, population projections are being formulated to assist in the update of forest plans. In southern California, the projected trend of explosive population growth combined with increased ethnic and racial diversity indicates four challenges for environmental management. First, patterns of recreation use on wildlands are likely to change, and management of these areas will have to address new needs. Second, as land-management agencies face changing constituencies, new methods of soliciting public involvement from ethnic and racial groups will be necessary. Third, growth in the region is likely to encroach upon wildland areas, affecting water, air, open space, and endangered species. Fourth, in order to address all these concerns in a climate of declining budgets, resource management agencies need to strengthen collaborative relationships with other agencies in the region. How environmental managers approach these changes has widespread implications for the ecological sustainability of forests in southern California.  相似文献   
156.
Up until the present, Jordan has relied almost exclusively on imported petroleum for its primary energy requirements. Encouraged by emerging technologies and recent fossil fuel discoveries, Jordanians are seriously examining exploitation of their own indigenous energy resources to meet projected mid- and long-term power requirements. The most prominent of the known resources is oil shale. This report addresses the oil shale-for-power-production option in Jordan. Under consideration are 20 MW and 50 MW demonstration units and a 400 MW commercial-scale plant. The report focuses on three areas: (i) the engineering feasibility of using Jordan's oil shale in a circulating fluidized bed combustion (CFBC) boiler; (ii) environmental aspects of the proposed oil shale-for-power plants(s); and (iii) the economic feasibility of the proposed plant(s). The results could be useful for other low- to middle-income countries considering oil shale as an option for power production.  相似文献   
157.
The transformation of nitrate was investigated in diverse stream sediments from six areas of Southern Ontario, Canada. Laboratory Experiments conducted with intact 0-5 cm depth sediment cores overlain with aerated 5 mg/l nitrate-N solution reveald considerable nitrate depletion during a six-day period as a resuit of denitrification and nitrate reduction to ammonium. Nitrification and ammonification also occurred simultaneously with nitrate reduction in many stream sediments. Mixed 0-5 cm depth sediments collected from 81 stream sites were used to examine the relationship between microbial nitrate removal and sediment characteristics. Rates of nitrate-N loss from aerated 5 mg/l nitrate-N solutions overlying these sediments ranged between 11 and 171 mg/m2/day for a 24-hour incubation period. Rates of nitrate loss for the 24-hour period exhibited a significant positive correlation (r=0.72) with sediment ammonium content. Organic carbon, total nitrogen and sediment texture also had significant but weak correlations with nitrate loss.  相似文献   
158.
Methodologies for the environmental analysis of total antimony and aqueous chemical speciation are critically reviewed, including preparation techniques for aqueous and solid matrices and the determination of solid state partitioning and recommendations are given for future research directions. Concentrations of total antimony commonly present in aqueous and solid environmental samples are readily determined using present day analytical techniques. This has resulted primarily from technological advances in microwave digestion for solid matrices and the development of plasma based analyte detection systems. ICP-AES and ICP-MS techniques are both utilised for the environmental analysis of total antimony concentrations. However, ICP-MS is increasingly favoured as a result of reduced spectral interferences and the potential for analyte detection in the pg mL(-1) range. Determination of aqueous antimony speciation presents a number of complex analytical challenges and highly selective separation and identification techniques are required prior to detection. The majority of published techniques including common applications of hydride generation are insufficiently selective for the determination of intrinsic chemical speciation and often only oxidation state data are obtained. The recent in-line applications of HPLC-ICP-MS offer the potential for highly selective separations of aqueous antimony species and determination of detailed chemical speciation data. However, considerable development work is required to optimise chromatographic separations and identify uncharacterised species resident in environmental systems. Analytical techniques to aid the determination of antimony's associations with solid environmental matrices include the application of chemical extraction procedures and leaching experiments. To date, this area of analytical research has received little attention and further studies are required to elucidate this aspect of antimony's environmental chemistry.  相似文献   
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