人口增长、经济增长、技术变化与环境变迁——中国现代环境变迁(1952—1990)

本文主要研究人口增长、经济增长、技术变化三大因素对环境质量变化的影响。作者提出环境变迁曲线,与人口转变曲线、工业化过程相联系,并划分了环境变迁四个阶段。根据环境变迁过程以及动因,在国际比较范围内,进一步说明了中国环境变迁的特点。作者认为,强化减少污染型技术因素是改善环境质量的主要途径,与此同时,坚持控制人口增长,以减少环境压力。     

灾害经济学中的减灾投入与成本问题

本文将经济学中的成本概念延伸至灾害学领域,构建出灾害成本的概念,并在该概念基础之上,建立了最优灾害成本经济模型,通过该模型探讨了防灾减灾的合理资金投入.     

建筑业安全问题的经济学分析

基于我国目前建筑业的安全现状和建筑业普遍存在的安全问题，从经济学的角度阐明了建筑业的安全问题是一种外部不经济现象，是企业为了追求利润的最大化而采取的经济活动所产生的后果，而导致这种现象的根本原因是市场或政府失灵，进而提出了改善安全状况的对策措施和建议。     

ECONOMIC ANALYSIS OF WETLAND RESTORATION ALONG THE ILLINOIS RIVER1

Creating and restoring wetland and riparian ecosystems between farms and adjacent streams and rivers in the Upper Mississippi River Basin would reduce nitrogen loads and hypoxia in the Gulf of Mexico and increase local environmental benefits. Economic efficiency and economic impacts of the Hennepin and Hopper Lakes Restoration Project in Illinois were evaluated. The project converted 999 ha of cropland to bottomland forest, backwater lakes, and flood‐plain wetland habitat. Project benefits were estimated by summing the economic values of wetlands estimated in other studies. Project costs were estimated by the loss in the gross value of agricultural production from the conversion of corn and soybean acreage to wetlands. Estimated annual net benefit of wetland restoration in the project area amounted to US$1,827 per ha of restored wetland or US$1.83 million for the project area, indicating that the project is economically efficient. Impacts of the project on the regional economy were estimated (using IMPLAN) in terms of changes in total output, household income, and employment. The project is estimated to increase total output by US$2,028,576, household income by US$1,379,676, and employment by 56 persons, indicating that it has positive net economic impacts on the regional economy.     

REASSEMBLING HETCH HETCHY: WATER SUPPLY WITHOUT O'SHAUGHNESSY DAM1

The Hetch Hetchy System provides San Francisco with most of its water supply. O'Shaughnessy Dam is one component of this system, providing approximately 25 percent of water storage for the Hetch Hetchy System and none of its conveyance. Removing O'Shaughnessy Dam has gained interest for restoring Hetch Hetchy Valley. The water supply feasibility of removing O'Shaughnessy Dam is analyzed by examining alternative water storage and delivery operations for San Francisco using an economic engineering optimization model. This model ignores institutional and political constraints and has perfect hydrologic foresight to explore water supply possibilities through reoperation of other existing reservoirs. The economic benefits of O'Shaughnessy Dam and its alternatives are measured in terms of the quantity of water supplied to San Francisco and agricultural water users, water treatment costs, and hydropower generation. Results suggest there could be little water scarcity if O'Shaughnessy Dam were to be removed, although removal would be costly due to additional water treatment costs and lost hydropower generation.     

灾害经济研究综述

本文在查阅了大量灾害科学方面的专著、期刊、学位论文和其它文献资料的基础上,对灾害经济学的定义、中外灾害经济的研究现状、灾害经济的基本规律和原理、灾害经济的评价方法、灾害经济学研究内容等六个方面进行了综述和基础理论探讨     

开发油气资源对新疆经济的带动作用

在实施西部大开发战略中,新疆丰富的油气资源日益显示具有广阔的开发前景,但这种资源优势究竟有多大,它对新疆经济快速发展的带动作用是否持久等都是值得思考的问题.从资源的自然禀赋和制度经济学角度出发,分析了当前形势下开发油气资源对新疆经济的影响,并提出了相应的对策.     

OPTIMAL PROFITS UNDER ENVIRONMENTAL CONSTRAINTS: IMPLICATIONS OF NUTRIENT AND SEDIMENT STANDARDS1

To reduce nonpoint source pollution from nutrient, chemical, and sediment runoff, a number of environmental policy standards have been proposed. Such standards could be used to reduce nonpoint source pollution from nutrient, chemical, and sediment runoff to impaired water bodies. State governments can use voluntary approaches to meet nonpoint source pollution reduction goals. However, the practices that lower net returns will not be voluntarily adopted by farmers. Crop rotations and tillage practices may help producers to comply with the environmental standards while minimizing losses in farm profits. This study compares runoff from crop rotation practices and conventional continuous row cropping systems in Mississippi. The results are compared for different tillage systems in order to examine robustness of results. Nutrient runoff and sediment runoff are simulated using the Erosion Productivity Impact Calculator (EPIC). Sensitivity analysis of the sediment and nitrate reductions at 15 percent, 25 percent, and 35 percent are conducted. Under these scenarios, net returns are optimized under environmental constraints, and the marginal cost of sediment reduction ranges from US$1.61 to US$9.63 per ton depending on soil conditions, while the corresponding nitrate and phosphorus reductions costs range from US$1.21 to US$7.08 per kg and from US$0.09 to US$31.91, respectively. The empirical results from this study indicate that a nitrate reduction policy is relatively less costly than a sediment reduction policy. The results also demonstrate the importance of geophysical conditions and policy costs, which vary across regions.     

Scrap tires to crumb rubber: feasibility analysis for processing facilities

Crumb rubber can be produced from scrap tires in a wide range of particle sizes and quality levels. Ideally, the revenue stream includes tipping fees paid to receive the raw materials; sales of variously-sized crumb products to different end-user markets; and potential sales of scrap metal and fiber contained within the tires. General demand has been increasing, and submarkets for crumb products are growing in size and variety. However, the optimistic expectations of potential investors and government agencies contrast sharply with the experiences of many current and former producers. Production planning and operation is complex, real-dollar crumb prices have fallen, and many producers recount difficulties finding stable markets and competing against newer, state-subsidized competitors. This paper examines the engineering economics of crumb rubber facilities. Following a literature review and interviews with producers, a financial model of a nominal processing operation was created to aid the analysis of different market, crumb size, and production scenarios. The profitability of a crumb facility appears to be particularly sensitive to crumb rubber prices, operating costs, and raw material availability. Better analysis of market and production impacts on financial viability for proposed processing facilities would aid overall market efficiency.     

ECONOMIC DECISION MAKING IN THE USE OF MEMBRANE DESALINATION FOR BRACKISH SUPPLIES1

ABSTRACT: An analysis is undertaken to determine the conditions under which membrane desalination becomes an economically preferable alternative for treating brackish water supplies. While membrane desalination is more expensive than conventional treatment, it affords benefits beyond those of conventional processes by reducing salinity related damages. An important and largely unexplored issue regards how the added cost of desalination compares to its benefits in terms of damages avoided. A comparative analysis is undertaken over a range of scenarios with the objective of identifying the treatment technology the leads to the lowest “total economic cost,” a term described by the sum of costs related to supply, treatment, and salinity related damages. Using data from a representative region, desalination yields the lowest total economic cost for source waters that exceed “threshold” salinity concentrations below 1,000 mg/l total dissolved solids (TDS). In instances where standard conventional processes require upgrades to maintain compliance with pending regulations (e.g., disinfection byproducts), the cost gap between membrane and conventional processes is reduced and the threshold concentration lowered. Given the inherent uncertainty in both treatment cost and damage estimates, a sensitivity analysis is conducted to determine which factors have the greatest impact on the treatment decision. Results suggest that considering salinity related damages when selecting a treatment technology makes membrane desalination of brackish waters economically attractive under a wider range of circumstances.