西方灾害经济学模型述评

对西方灾害经济学研究应用的模型技术进行了概略的综述,包括投入产出和线性规划相结合的模型、投入产出和生产函数相结合的模型、一般均衡模型、系统动力学模型以及社会核算矩阵模型五种,并对这些模型的优缺点进行了简要的评析．     

ON THE CAPACITY-EXPANSION OF DESALINATION PLANTS AND STORAGE TANKS1

ABSTRACT A mathematical programming model is structured to find the optimal time and capacity expansion path of desalination plants and storage tanks for a hypothetical community which depends on desalination as its sole, or major, water supply source. The objective is to determine the least costly combination of sues and times of installation (of both desalting plants and storage tanks) which can meet a rising water demand over a finite planning horizon. The optimality criterion used in the model is based on two major economic elements: the economies of scale inherent in such facilities and the time-value of money represented by the interest rate, the former favoring large capacities and the latter small capacities. The model is applied using three population growth patterns and two interest rates. The water demand components for every year in the planning period are computed using empirical formulas which are based on population and other basic data. The model is solved for each of the above cases with the aid of a computer program based on the method of feasible conjugate directions. The results clearly reflect the balance between the economies of scale and the time-value of money under every demand growth function.     

Impact of Animal Welfare on Costs and Viability of Pig Production in the UK

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.     

COST‐EFFECTIVE POINT‐NONPOINT TRADING: AN APPLICATION TO THE SUSQUEHANNA RIVER BASIN1

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.     

乡镇企业环境问题的经济学分析及环境保护手段的选择

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。     

Birth of a megaproject: Political economy of flood control in bangladesh

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.     

The economic effects of stratospheric ozone depletion on U.S. agriculture: a preliminary assessment

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.     

THE OPTIMAL STEADY-STATE IN GROUNDWATER MANAGEMENT1

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.     

职业卫生管理中制度与文化建设的探讨

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。     

Finding Water for Growth: New Sources,New Tools,New Challenges1

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.