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491.
H. L. I. Bornett J. H. Guy P.J. Cain 《Journal of Agricultural and Environmental Ethics》2003,16(2):163-186
The European Union welfare standardsfor intensively kept pigs have steadilyincreased over the past few years and areproposed to continue in the future. It isimportant that the cost implications of thesechanges in welfare standards are assessed. Theaim of this study was to determine theprofitability of rearing pigs in a range ofhousing systems with different standards forpig welfare. Models were constructed tocalculate the cost of pig rearing (6–95 kg) in afully-slatted system (fulfilling minimum EUspace requirements, Directive 91630/EEC); apartly-slatted system; a high-welfare,straw-based system (complying with the UK-basedRoyal Society for the Prevention of Cruelty toAnimals, Freedom Food standards) and afree-range system. The models were also used toassess the consequences of potential increasesin space allowance, and to estimate the cost ofrearing pigs under organic standards.The cost of rearing pigs ranged from92.0 p/kg carcass weight (cw) and 94.6 p/kgcw forthe partly-slatted and fully-slatted systems,to 98.8 p/kgcw and 99.3 p/kgcw for the FreedomFood and free-range systems respectively. Whenspace allowance was increased by 60% to levelsin a recent proposal to revise pig welfareDirective (91/630/EEC), the rearing costs wereunchanged for the free-range system but rose by4.6 p/kgcw for the fully-slatted system. Rearingcosts under organic standards were 31% higherthan in the free-range system. These resultssuggest that improved pig welfare can beachieved with a modest increase in costAt present, price premiums received for meatproduced under high welfare systems in the UKoffset the higher costs of production in thesesystems. To ensure profitability in the longterm, it is important that these premiums aremaintained. 相似文献
492.
Richard D. Horan David G. Abler James S. Shortle Jeff Carmichael 《Journal of the American Water Resources Association》2002,38(2):467-477
ABSTRACT: Point‐nonpoint trading has been suggested as a relatively efficient approach for reducing nutrient pollution in the Chesapeake Bay and elsewhere. However, relatively little economic research has examined the design of trading programs involving nonpoint sources. The purpose of this paper is to investigate the economics of several fundamental design choices for point‐nonpoint trading programs. The Susquehanna River Basin (SRB) in Pennsylvania as an example, although many of the insights should generally apply to other regions as well. 相似文献
493.
邱伟娟 《中国环境管理干部学院学报》2004,14(2):55-59
乡镇企业的发展一方面给我国农村劳动力提供了大量的就业机会,加快了我国的城市化进程,为我国的经济做出了重要的贡献;另一方面,由于生产要素、利益驱动等众多因素的影响,乡镇企业给资源和环境造成了巨大的耗竭和破坏。本文主要从经济学的角度来探究乡镇企业发展带来的环境问题的根源,进而选择一套适合我国乡镇企业特点的环境保护手段。 相似文献
494.
James K. Boyce 《Environmental management》1990,14(4):419-428
A major flood control initiative has been launched in Bangladesh under the coordination of the World Bank. The bank's five-year
Action Plan is intended to initiate a long-term investment program, the specifics of which remain to be determined. Long-term
proposals under consideration include the construction of massive embankments along the great rivers of the Bangladesh delta.
The wisdom of such a “structural solution” to Bangladesh's flood problems can be questioned on economic, environmental, and
technical grounds. Regrettably, the decision-making process has not encouraged wide debate on these questions. 相似文献
495.
The adverse effects of stratospheric ozone depletion on human health and welfare is a major environmental concern. One potential welfare effect is reduction in plant productivity, including agricultural crops, due to increased UV-B radiation and tropospheric ozone formation. This paper evaluates the economic effects of potential changes in crop yields due to hypothetical depletions in stratospheric ozone over regions of the U.S.A. Results suggest that increases in tropospheric ozone due to a 15 per cent stratospheric ozone depletion may cause economic losses of around 0·9 billion dollars. Combined effects of both tropospheric ozone and UV-B radiation range from 1·3 to 2·5 billion dollars. These estimates are preliminary, given the high degree of uncertainty in key plant science and aerometric data. 相似文献
496.
Bruce W. Vigon 《Journal of the American Water Resources Association》1985,21(2):179-184
Nonpoint source pollution remains as the primary reason for the designation of many of the Nation's streams as “water quality limited.” This means that even with the application of technology-based effluent limitations on point sources, ambient water quality standards will not be met. This paper explores several of the reasons why nonpoint sources are so difficult to come to grips with. These reasons include: (1) the inability to expand the definition of nonpoint sources to encompass nonengineering attributes, (2) the relatively primitive state of characterizing nonpoint sources, (3) the lack of prior success in conducting programs to study and alleviate nonpoint problems, and (4) an uncertain approach to providing incentives for control practices. 相似文献
497.
Keith C. Knapp Eli Feinerman 《Journal of the American Water Resources Association》1985,21(6):967-975
Groundwater use is likely to be inefficient in the absence of regulation and hence there is substantial interest in optimal groundwater withdrawals over time. Under an optimal regime withdrawals, pumping lifts, and profits converge to steady-state levels. In this paper we show that optimal steady-state lifts, withdrawals, and marginal user costs can be readily calculated for multi-cell models of confined aquifers. Applications to the design of economically efficient groundwater management policies are discussed, comparisons to previous work and to the safe yield concept are made, and an illustrative example is given. 相似文献
498.
笔者借助中国职业卫生管理现状的数据,结合12年跨国公司的管理实践,运用新制度经济学的理论和引入国际职业卫生管理绩效随时间演变模型的方法,针对国内职业卫生管理存在的问题和采取的对策进行探讨与研究。结果表明,目前中国职业卫生管理现状处于初级阶段,制度和文化的建设是当前职业卫生问题的最深层原因。职业卫生管理中的制度及文化建设,对职业卫生管理绩效水平起着决定性的作用,是解决问题的最首要、最根本的手段。研究成果:文化是统帅,制度是载体,是实现理念转变的具体手段。总结并提出职业卫生文化及制度建设对策的4个要素:理念的树立与融合;全员全程参与;突出能力管理概念;量化诚信的绩效监察制度。 相似文献
499.
500.
Ellen Hanak 《Journal of the American Water Resources Association》2007,43(4):1024-1035
Abstract: Rapidly growing regions such as the western United States face difficult challenges in mobilizing new water supplies to meet new demands. Environmental concerns have curtailed the scope for large new surface storage projects, and widespread basin overdraft has limited ground water’s potential as a source of expansion. Drawing on the California experience, this article explores modern water planning approaches, which focus on a portfolio of options including nontraditional sources (recycling, desalination, underground storage) and more efficient use of existing supplies (conservation and water marketing). It reviews the advantages and drawbacks of the elements of the portfolio, provides examples of innovative planning approaches, and assesses the role for supportive government policies. 相似文献