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31.
Norman K. Whittlesey Kenneth C. Gibbs Walter R. Butcher 《Journal of the American Water Resources Association》1978,14(3):663-678
ABSTRACT: Increased irrigation as a means of achieving economic development can impose significant social costs on the state or region of growth. The growth in population induced by additional irrigation will require new roads, water and sewage facilities, schools, fire and police protection, etc. Also the increased energy demands due to irrigation and growth in economic activity must be met. Capital investments required to service these needs of new development can become very large. This study attempts to measure such social overhead costs or irrigation development for some specific irrigation project areas of Eastern Washington. It is shown that investment costs in overhead items can reach $2,000 per acre irrigated or $70,000 per job created. Alternatively, the annual costs can equal $180 per acre or $6,700 per worker. These costs must be paid locally through increased taxes, utility rates, or costs for services. 相似文献
32.
G. J. Kelnhofer 《Journal of the American Water Resources Association》1978,14(6):1423-1428
ABSTRACT: There are many factors, other than economic efficiency, which must be considered in judging the merits of proposed investments in the inland navigation system. No satisfactory formula exists for deciding the net worth of public investments in water resources projects. Such a measure would not be accepted because these investments can serve conflicting goals. Political, rather than technical, judgments are required to resolve these goal conflicts. 相似文献
33.
Current political conditions, primarily budgetary uncertainty, and the related reluctance to make funding commitments for
future generations, have raised questions about the costs of conservation and environmental protection that have not previously
been asked. As Federal investments are scrutinized and budgets become ever more constrained, the costs associated with environmental
requirements could begin to be of greater importance and to influence decisions on Federal projects. In response to concerns
about the U.S. Army Corps of Engineers (Corps) spending under the Endangered Species Act (P.L. 93-205) (ESA), a limited investigation
was performed to determine the accuracy of reported Corps expenditures. The investigation showed that, for particular groups
of species, actual conservation costs for threatened and endangered species may be twice the amounts previously reported in
the annual ESA expenditure reporting to the U.S. Fish and Wildlife Service. In light of this finding, the Corps has sought
a means to provide more accurate and consistent reporting of expenditures for addressing threatened and endangered species.
A Species Costs Template (template) has been developed to identify the types and magnitude of costs related to the ESA and
to counteract the impediments (legal, institutional, and practical) to underreporting costs. The template will be used by
the Corps for reporting ESA costs beginning with Fiscal Year 2005 (FY05) (reported in January 2006). Five broad categories
of expenditures (effects determination costs, ESA protection and conservation costs, equipment costs, opportunity costs, and
other species costs) are identified by the template. 相似文献
34.
An Interpretive Study of Yosemite National Park Visitors’ Perspectives Toward Alternative Transportation in Yosemite Valley 总被引:1,自引:0,他引:1
White DD 《Environmental management》2007,39(1):50-62
The National Park Service (NPS) is increasingly focusing on alternative transportation systems in national parks to address
environmental and social problems arising from a historical reliance on personal automobiles as the primary means of visitor
access. Despite the potential advantages, alternative transportation may require a reorientation in the way that Americans
have experienced national parks since the advent of auto-tourism in the early twentieth century. Little research exists, however,
on visitor perspectives towards alternative transportation or the rationale underlying their perspectives. It remains unclear
how transportation systems affect visitors’ experiences of the park landscape or the factors influencing their travel behavior
in the parks. This report presents an interpretive study of visitor perspectives toward transportation management in the Yosemite
Valley area of Yosemite National Park, California. Qualitative analysis of 160 semi-structured interviews identified individual
psychological factors as well as situational influences that affect visitors’ behavior and perspectives. Individual psychological
factors include perceived freedom, environmental values and beliefs, prior experience with Yosemite National Park and other
national parks, prior experience with alternative transportation in national parks, and sensitivity to subjective perceptions
of crowding. Situational factors included convenience, access, and flexibility of travel modes, as well as type of visit,
type of group, and park use level. Interpretive communication designed to encourage voluntary visitor use of alternative transportation
should focus on these psychological and situational factors. Although challenges remain, the results of this study suggest
approaches for shaping the way Americans visit and experience their national parks to encourage environmental sustainability. 相似文献
35.
As part of the Paris climate agreement, countries have submitted (Intended) Nationally Determined Contributions (NDCs), which includes greenhouse gas reduction proposals beyond 2020. In this paper, we apply the IMAGE integrated assessment model to estimate the annual abatement costs of achieving the NDC reduction targets, and the additional costs if countries would take targets in line with keeping global warming well below 2 °C and “pursue efforts” towards 1.5 °C. We have found that abatement costs are very sensitive to socio-economic assumptions: under Shared Socioeconomic Pathway 3 (SSP3) assumptions of slow economic growth, rapidly growing population, and high inequality, global abatement costs of achieving the unconditional NDCs are estimated at USD135 billion by 2030, which is more than twice the level as under the more sustainable socio-economic assumptions of SSP1. Furthermore, we project that the additional costs of full implementation of the conditional NDCs are substantial, ranging from 40 to 55 billion USD, depending on socio-economic assumptions. Of the ten major emitting economies, Brazil, Canada and the USA are projected to have the highest cots as share of GDP to implement the conditional NDCs, while the costs for Japan, China, Russia, and India are relatively low. Allowing for emission trading could decrease global costs substantially, by more than half for the unconditional NDCs and almost by half for the conditional NDCs. Finally, the required effort in terms of abatement costs of achieving 2030 emission levels consistent with 2 °C pathways would be at least three times higher than the costs of achieving the conditional NDCs – even though reductions need to be twice as much. For 1.5 °C, the costs would be 5–6 times as high. 相似文献
36.
依据废渣特性的理论分析,通过对废渣成分以及采用废渣配料前后生料、熟料的成分分析及性能测试,调整生料配比和改变水泥窑操作工艺,通过生产实践数据分析,说明了利用钢渣和粉煤灰作为铁质和铝质校正材料生产普通硅酸盐水泥熟料,不仅可以提高水泥熟料产量和质量,而且可以有效地降低熟料生产成本和产品综合能耗。促进了企业节能减排和资源综合利用的可持续发展。 相似文献
37.
公共资源与最优产权选择 总被引:1,自引:1,他引:0
公共资源是指在产权界定过程中,资源所有者被迫放弃或者没有进行产权界定的资源部分,而产权界定本质上是划分公共资源归属权的过程。根据组织对公共资源控制权的性质,将其分为两类——组织间公共资源和组织内公共资源,并据此将产权界定、生产和交易纳入同一个分析框架中。通过分析,认为随着公共资源范围的变化,不同产权形成一个相互联系和转化的系列,即从资源非稀缺条件下的纯公共产权到资源全为废弃物的纯公共产权系列;不可交易的所有权是产权系列中的特殊形式,私人产权和俱乐部产权是这一系列中的过渡形式;组织内和组织间的均衡博弈结构决定最优产权的具体选择形式。 相似文献
38.
Patrick C. Mann John L. Mikesell 《Journal of the American Water Resources Association》1979,15(5):1301-1307
ABSTRACT: Several factors theoretically affect the cost behavior of water systems. These factors include scale, consumer density, and per capita usage. This analysis examines the several possible influences on the unit costs of water service. The statistical analyses indicate that among the factors of scale, per capita use, and consumer density, only the first two factors are important influences on water system costs. Water consumers appear to benefit from being served by large systems and being located in service areas characterized by relatively high per capita consumption. There is little statistical evidence indicating that more dense areas can be provided water service at lower costs than less dense areas. 相似文献
39.
Energy intake and expenditure on natural foraging trips were estimated for the seed-harvester ants, Pogonomyrmex maricopa and P. rugosus. During seed collection, P. maricopa foraged individually, whereas P. rugosus employed a trunk-trail foraging system. Energy gain per trip and per minute were not significantly different between species. There was also no interspecific difference in energy cost per trip, but energy cost per minute was lower for P. maricopa foragers because they spent on average 7 min longer searching for a load on each trip. Including both unsuccessful and successful foraging trips, average energy gain per trip was more than 100 times the energy cost per trip for both species. Based on this result, we suggest that time cost incurred during individual foraging trips is much more important than energy cost in terms of maximizing net resource intake over time. In addition, because energy costs are so small relative to gains, we propose that energy costs associated with foraging may be safely ignored in future tests of foraging theory with seed-harvesting ant species. 相似文献
40.
Although set-up costs are prevalent and substantial in natural resource extraction, it is known that a Walrasian competitive equilibrium cannot exist in simple extraction models with set-up costs. This paper demonstrates that this result is sensitive to the assumption of unlimited extraction capacity and derives sufficient conditions for existence. An equilibrium exists if extraction is limited such that each firm earns sufficient surplus to cover its set-up costs or if firms choose extraction capacity subject to non-increasing returns. The resulting competitive equilibrium price either grows at the rate of interest when total extraction is below industry capacity or is constant when industry capacity is fully utilized. In the equilibrium, identical deposits are opened simultaneously, and set-up costs for new deposits are incurred when the industry has excess capacity rather than when capacity is fully utilized. 相似文献