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141.
Rusidan Lubis Michael V. Martin B. Starr McMullen 《Journal of the American Water Resources Association》1987,23(4):673-680
ABSTRACT: Grain transportation is a major economic activity on the multiple use Snake-Columbia River System. Congress is currently considering increased transportation user fees aimed at recapturing federal expenditures for waterway operations and maintenance. Three types of fee structure and four levels of cost recovery are evaluated using a network program model. In each case traffic is diverted away from the river to other Puget Sound ports via truck and rail transport modes. Grain shippers in the region will be adversely affected by a higher transport bill. The Lower Columbia River port economic activities will be negatively affected; however, competitive uses of the river, recreation, and hydroelectric generation will likely benefit modestly. 相似文献
142.
Josiah Akinsanmi Gregory M. Perry 《Journal of the American Water Resources Association》2002,38(1):101-110
ABSTRACT: Traditional focus on reducing one environmental externality may cause another externality to increase. This article examines the environmental and economic costs of abating soil loss and (or) nitrate leaching through alternative optimal production systems in the nonirrigated farming systems of Northeastern Oregon. Models estimating soil loss and nitrate‐nitrogen leaching rates associated with current production processes, are linked to a Multi‐Objective Programming (MOP) model. The results show that site specific conditions influence the level of abatement expenditures and optimal production strategies to reduce soil loss and leaching rates. Moreover, while existing production strategies are effective in reducing soil loss at little cost, no strategies could be identified to reduce nitrate leaching rate on some soils. 相似文献
143.
Michael C. Appleby Neil Cutler John Gazzard Peter Goddard John A. Milne Colin Morgan Andrew Redfern 《Journal of Agricultural and Environmental Ethics》2003,16(4):395-408
This paper is the report of a meetingthat gathered many of the UK's most senioranimal scientists with representatives of thefarming industry, consumer groups, animalwelfare groups, and environmentalists. Therewas strong consensus that the current economicstructure of agriculture cannot adequatelyaddress major issues of concern to society:farm incomes, food security and safety, theneeds of developing countries, animal welfare,and the environment. This economic structure isbased primarily on competition betweenproducers and between retailers, driving foodprices down, combined with externalization ofmany costs. These issues must be addressed by acombination of legislation, restructuring ofthe market, and use of public funds. Themeeting included workshops that made otherrecommendations for research and education. Themost urgent requirement is recognition thatchange is needed and development of a visionfor what that change must achieve. 相似文献
144.
Alan R. Collins Scott Steinback 《Journal of the American Water Resources Association》1993,29(2):199-209
ABSTRACT: About one-third of all West Virginians obtain domestic water from private water wells. In this research, mail and telephone surveys were used to investigate household responses to bacteria, mineral, and organic chemical contamination of domestic water supplies. Of households who were informed of contamination and acknowledged the problem, over 85 percent took action to avoid exposure to water contamination problems. The most common action was to clean and/or repair the water system (55.9 percent of valid surveys). Approximately 45 percent of households made investments of either a water treatment system, a new water source, or correction of contamination source. The average, annual economic cost of rural household actions was $320 for bacteria, $357 for minerals, and $1,090 for organic contamination. These economic costs represent a lower bound estimate for rural household willingness-to-pay (WTP) for a reduction in domestic water contamination from government action. On average, investment actions had lower annual economic costs than noninvestment actions of boiling and hauling water so that households who undertook investment actions in response to water contamination would have a lower WTP for government action to reduce water contamination. When effectiveness of water treatment systems was evaluated, treatment systems which require minimal household maintenance were found to reduce exposure to water contamination to safe levels as households intended when they installed the system. Treatment systems which were commonly ineffective included those which required continual maintenance (e.g., chiorinators) or were not designed to solve the contaminant problem for which they were purchased (e.g., filter systems for bacteria). 相似文献
145.
146.
Andrew B. Rosenberg David A. Newburn Charles A. Towe 《Journal of the American Water Resources Association》2023,59(2):376-395
Stream restoration is one of the most widely used interventions to mitigate urban stormwater impacts and improve water quality. Government agencies have typically focused urban stream restoration efforts on public lands that they already own, even though a substantial portion of stream miles in highly urbanized areas occur on privately owned land. Yet, limited research exists to distinguish household willingness to pay (WTP) for stream restoration occurring on private versus public land. In this study, we use a choice experiment to analyze how household WTP for stream restoration attributes vary by land ownership and distance to the restoration project. Our empirical results indicate that streambank stabilization approaches have positive WTP estimates that are substantially larger in magnitude than those related to riparian vegetation management for clearing or planting trees. In general, estimated total household WTP for each of the four restoration design scenarios on public land is higher than when the same restoration design is located on private land. Nonetheless, estimated household WTP for each restoration design scenario on private land is substantial, retaining the majority of the value found on public land in all cases. 相似文献
147.
当前,生态产品价值实现探索实践中面临生态系统服务度量难、核算难、货币化难、交易难等基础性难题,导致生态产品价值核算体系不统一、生态产品市场交易机制不完善、各类生态产品交易平台不规范、绿色金融滞后、绿色发展市场化激励机制不足等问题。本文从最关键的生态产品价值理论出发,梳理生态产品价值实现困境的根源和理论基础,并尝试提出可能的多元核算方法与热力学、景感学、经济学相结合的实践解决路径,形成不同单位的统一核算标的物。通过探索利用区块链、大数据等科技赋能生态产品价值实现,提出构建生态资产加密数字货币化的可能性,并进一步形成不同生态产品的价格形成机制、成本监审制度和价格调整机制,完善生态产品市场交易机制,建立统一的生态产品交易平台,促进绿色金融发展,推动自然资源管理能力现代化。 相似文献
148.
149.
以曼么村为例 ,从环境经济学的观点出发 ,对热带森林 -砂仁生态系统的可持续性从经济及环境、生态等方面进行了分析。发现种植砂仁后 ,砂仁的经济效益的递增率不如资源环境成本的递增率快。生态环境的破坏 ,大大降低了砂仁的产量 ,从而更使得种植砂仁的经济效益停滞不前。由砂仁的外延式生产转为内涵式生产 ,采用轮作的经营方式 ,能很好地实现砂仁的持续种植 相似文献
150.
Ereney Hadjigeorgalis 《Journal of the American Water Resources Association》2008,44(3):594-605
Abstract: Managing drought in agriculture has taken on growing importance as population growth and environmental concerns place increasing pressures on agricultural water use. One alternative for agricultural water resource management in areas of recurrent drought is allocation through market mechanisms. While past research has aimed to explain why farmers are reluctant to participate in already established water markets, this research seeks to identify the appropriate market mechanism given farmers’ preexisting attitudes toward water markets. Statistical analysis of survey data from 166 farmer interviews in the Rio Grande Basin indicate that farmers are significantly more likely to participate in short‐term water mechanisms, such as spot water markets and water banks than in permanent transfer mechanisms, particularly those that fully separate water rights from land. In sharp contrast to expectations, the choice of market mechanism did not differ significantly between farmers based on their a priori intention to buy, sell or both buy and sell in these markets. Choice of market mechanism also did not differ among farmer types although small, lifestyle or hobby farmers clearly preferred spot water markets to other types of short‐term mechanisms. Evaluating these attitudes a priori may help to design more suitable water market mechanisms for the basin. 相似文献