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41.
42.
The commercial fishing fleet in New Bedford, Massachusetts, USA, harvests seafood on George’s Bank, home of one of the nation’s most productive fisheries. We calculated the energy return on investment (EROI) and carbon intensity of protein harvest in the New Bedford fisheries from 1968 to 1988. EROI is the ratio of the energy content of the edible fish protein harvested to the quantity of fossil fuel energy used directly in the harvesting process. Carbon intensity is the quantity of carbon dioxide (CO2) released (from the burning of fossil fuels) per calorie of edible fish protein harvested. The results show that the EROI of protein harvest declined from 0.18 to 0.028 from 1968 to 1988, indicating that the energy used to harvest seafood increased from about 6 to 36 kcal of fuel for each kilocalorie of protein harvested. The quantity of CO2 released per calorie of edible fish protein is a linear function of energy use and therefore increased in a similar manner. During this period there was a large increase in fishing effort (caused by the increase in the real price of seafood products, favorable tax treatment for new vessel construction, and low interest loans from the government), and a decline in several important species of fish. The results suggest that fishing pressure could be managed effectively by the regulation of fuel use by the fleet. Despite the increase in the price of many seafood products, fishermen absorbed many of the costs of increasing scarcity in the form of longer working hours and fewer men per vessel.  相似文献   
43.
The use of organic farming technologies has certain advantages in some situations and for certain crops such as maize; however, with other crops such as vegetables and fruits, yields under organic production may be substantially reduced compared with conventional production. In most cases, the use of organic technologies requires higher labor inputs than conventional technologies. Some major advantages of organic production are the conservation of soil and water resources and the effective recycling of livestock wastes when they are available.  相似文献   
44.
Chile ratified the Montreal Protocol in 1990 which sets out an agenda for the reduction and then elimination of ozone depleting substances (ODS); however, by 1998 the country had not yet defined a strategy to encourage greater compliance, so that in the same year the National Environmental Commission decided to examine the policy options available. This paper examines the process followed to develop this strategy. As a first step it was necessary to look at how far the implicit policy of "business as usual" could be stretched without jeopardizing Chile's compliance obligations. A second step included quantifying compliance costs and their impact on different policy instruments and so policy choice. Finally, the attitudes of decision-makers or participants were identified, by interviews with officials of the different public agents involved, in order to weigh their views about policy. A strategy was proposed, based on this information, which the Chilean regulator has used, although not in its entirety. The methodology developed could well be useful for developing-country Protocol signatories building their own appropriate compliance strategy.  相似文献   
45.
减灾事业的发展和综合减灾   总被引:14,自引:1,他引:14  
中国减灾事业的发展史可分3个阶段:第一阶段是新中国成立以前的几千年,减灾活动以赈灾为主,帝王“祭天求恕”,“防灾吏制”,安抚于民。清末民初1800至1949年间计发生巨灾25起,死亡4993万余人,总灾亡则近亿,年均灾亡60万人以上,这段惨痛的灾况记下了十分难得的灾情史,泣血于残野。新中国成立后,在“为人民服务”的思想指导下,为减轻灾害损失,逐步建立了气象、水利、农林、地震、海洋、地质等专业的灾害科技与减灾工程,政府并组织社会兼事抗灾、救灾、应急减灾,国家减灾实力快速增长,已取得突出减灾实效,这个阶段比第一阶段灾亡人数下降了90%以上,但年均灾亡人口仍有1.2万人左右。该阶段的工作特点是以单灾种纵向体系为主,不同灾类的监测、预报水平尚高低不一,这与成灾机理的难易程度和工作条件的强弱有关。21世纪初,随全球增温之势锐升,多类极端灾变遍及各洲,促使许多国家发动全社会人众共同探求“综合减灾”之路;我国政府已迅即开展全社会应急减灾行动,开启了“综合减灾”之先声,这是减灾事业步入第三阶段的先导。综合减灾应该是全社会相关部门和民众的统一行动。目前尚有3个问题需要弄清楚,一是多种自然灾害之间成灾机理相关性的研究,其对象是灾害群与灾害链;二是全社会减灾要素综合运作预案的优选;三是如何核算减灾投入与社会可持续发展之正、负效应关系。  相似文献   
46.
Farmers from four irrigation districts in Texas and California were questioned about water conservation practices they are now using, those they plan to adopt, and potential incentives that government might offer to induce still further water conservation on their part. While responses differed somewhat from place to place and among individual farmers, the general results were: a) farmers reported that “water conservation” is not new to them, it is something they practice regularly; b) recent innovations such as laser controlled land leveling devices have permitted some substantial water use reductions in recent years; and c) even greater incentive mechanisms that government could provide and that farmers would accept as useful incentives, such as long term low interest loans for water saving equipment, would probably not be able to reduce water use in agriculture much further than 15 percent below current levels. It is recommended nonetheless that Federal agencies and local water districts and individuals should nonetheless pursue water conservation training and education programs, demonstrations of conjunctive use and water banking opportunities for water saving, and increased loan programs for installation of water saving equipment.  相似文献   
47.
ABSTRACT: The Illinois v. Milwaukee Federal District Court decision is the most far reaching application yet of the federal common law of nuisance to interstate water pollution conflicts. Although a Federal Appelate Court recently rescinded part of the district court decision, Milwaukee must still upgrade its metropolitan sewage system to a level beyond that required by federal and state regulations. The improvements must be completed with or without federal aid. The case points out the apparent inability of the Clean Water Act, the most comprehensive federal legislation affecting the nation's water quality, to deal with certain interstate water quality conflicts. The Milwaukee decision could set a precedent for similar settlements elsewhere which may in turn affect the U.S. Environmental Protection Agency's water quality clean up program. A more integrated, ecosystem conscious approach to management of shared water resources (e.g., the Great Lakes) would help reduce the need for court decisions like Illinois v. Milwaukee.  相似文献   
48.
ABSTRACT: The density and distribution of land uses has important consequences for the planning of sewerage systems and for the costs of these systems. This paper examines these consequences using a simplified service area model. The model determines the area to be served by a central waste treatment plant, where alternative on-lot disposal systems are also available. The model is applied to various urban area configurations, which are summarized by their total populations and by their population density distributions. Both minimum regional cost and minimum local cost service area configurations are determined. In addition, the sensitivity of the model to the parameters of the cost and population density functions is assessed. It is found that the model is most sensitive to the parameters of the collection cost function.  相似文献   
49.
This paper discusses why estimates of the benefits of reduced air pollution differ in accordance with the approach used. Estimates based on bottom-up studies of the damage costs related to air pollution usually turn out much lower than estimates based on assessments of the utility of reduced air pollution, obtained for instance by willingness to pay assessments. This is usually explained by the fact that the willingness to pay approach includes the utility aspect of non-market values, and for this reason, it is often preferred to the damage cost approach. This is, however, not the whole story. The paper shows why alternative approaches should not be considered as being in conflict, but rather as means to get supplementary information necessary to put a value on environmental quality. Information from bottom-up assessments of damage costs and from studies of the willingness to pay is used in a macroeconomic model to carry out an evaluation of the social costs of energy saving measures in Hungary.  相似文献   
50.
发展中国家灾害经济的特点、成因及对策   总被引:10,自引:3,他引:7  
何爱平 《灾害学》2000,15(2):91-96
发展中国家人口众多,经济技术落后,酱稀缺,抗灾能力低,防灾意识不强,加多不合理经济活动对环境的过度干预以及发达国家转嫁环境灾害和社会危机,致使发展中国家产生灾害的潜在因素日益增加,灾害的成灾损失越来越严重,灾害对经济发展的影响与经济因素对灾害的影响都在日益加深,形成恶性循环。本文从经济学角度提出了防灾减灾就采取的主要对策。  相似文献   
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