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281.
MICHAEL R. BOSWELL ROBERT E. DEYLE RICHARD A. SMITH E. JAY BAKER 《Environmental management》1999,23(3):359-372
/ A method is presented for estimating probable public costs resulting from damage caused by hurricanes, measured as local government expenditures approved for reimbursement under the Stafford Act Section 406 Public Assistance Program. The method employs a multivariate model developed through multiple regression analysis of an array of independent variables that measure meteorological, socioeconomic, and physical conditions related to the landfall of hurricanes within a local government jurisdiction. From the regression analysis we chose a log-log (base 10) model that explains 74% of the variance in the expenditure data using population and wind speed as predictors. We illustrate application of the method for a local jurisdiction-Lee County, Florida, USA. The results show that potential public costs range from $4.7 million for a category 1 hurricane with winds of 137 kilometers per hour (85 miles per hour) to $130 million for a category 5 hurricane with winds of 265 kilometers per hour (165 miles per hour). Based on these figures, we estimate expected annual public costs of $2.3 million. These cost estimates: (1) provide useful guidance for anticipating the magnitude of the federal, state, and local expenditures that would be required for the array of possible hurricanes that could affect that jurisdiction; (2) allow policy makers to assess the implications of alternative federal and state policies for providing public assistance to jurisdictions that experience hurricane damage; and (3) provide information needed to develop a contingency fund or other financial mechanism for assuring that the community has sufficient funds available to meet its obligations. KEY WORDS: Hurricane; Public costs; Local government; Disaster recovery; Disaster response; Florida; Stafford Act 相似文献
282.
283.
我国城市污水处理的有效措施 总被引:16,自引:0,他引:16
我国水环境污染和水资源短缺,促进了污水处理厂的建设,而污水处理工艺在很大程度上决定了污水处理厂的投资、基建费用、用地和运行管理费用。文章介绍了我国有污水处理厂的工艺、投资和运行费用。结合我国的基本国情,提出了建立经济有效的处理工艺的措施。 相似文献
284.
Summary. Induction of secondary metabolites to herbivore damage is a widespread phenomenon among plants and serves to enhance resistance
by reducing suitability or increasing toxicity of foliage. Post-damage responses of primary metabolites are less well known;
reductions in primary metabolites may increase resistance by decreasing palatability or nutritional suitability for herbivores
or by potentiating toxicity of secondary metabolites. In this study, we examined response to simulated herbivory in Pastinaca sativa, the wild parsnip, in both primary and secondary metabolites. We found that induction of secondary metabolites in response
to damage is largely restricted to a single class of compounds, the furanocoumarins. These prooxidant compounds are known
to be toxic to a wide variety of insect herbivores. The only primary metabolite that responded to damage was total soluble
protein, which increased significantly 24 h after damage. After 24 h, the correlation between total furanocoumarins and total
sugars was significant and negative (r = − 0.697). This correlation likely reflects an independent response of sugar to damage,
rather than a diversion of resources into furanocoumarin production, inasmuch as this correlation at 3 h, after furanocoumarin
induction had taken place, was not significant. In other secondary metabolite pathways, damage produced a significant decline
in farnesene and a C-16 unsaturated fatty acid, 7,10,13-hexadecatrienoic acid, each of which may potentiate the furanocoumarin
defense response. Farnesene may enhance photooxidative activation of the furanocoumarins and 7,10,13-hexadecatrienoic acid
may serve as a precursor to jasmonic acid, a key hormone in regulating induction responses. With few key exceptions, quantities
of both primary and secondary metabolites in wild parsnip foliage are unaffected by damage. Those that are affected may well
play a role in resistance of parsnips to herbivores.
Received 1 July 1998; accepted 28 September 1998. 相似文献
285.
In the context of global climate change,the internalization of negative externality,which is brought about by the traditional mode of economic growth,has become an inevitable choice.In order to achieve the internalization,it is necessary to make innovations on the market mechanism and system,find the value of environmental capital,establish a new mode of economic growth based on environmental capital,and then transform the environmental capital,an exogenous factor of economic growth,into an endogenous factor.Of this,the key of market mechanism and system innovation is the financial innovation that is based on environmental capital and negative externality;the government defines the initial property right of environmental resources and establishes environment energy trading market,so as to guide enterprises to trade environmental resources(represented by carbon emission permit trading) based on the Clean Development Mechanism,and to vigorously develop environmental finance and carbon finance. 相似文献
286.
人力资本积累与地区经济增长的联动关系分析 总被引:1,自引:0,他引:1
胡永远 《中国人口.资源与环境》2011,21(12)
人力资本积累与地区经济增长差距的关系问题,是国内外理论界关注的焦点之一.为什么中国的地区经济增长在经济转型期20世纪80年代呈现收敛而90年代后发散?人力资本究竟是怎样作用于经济增长的?已有的经验研究没有考虑人力资本积累自身的收敛性,因而没有考虑到人力资本积累与地区经济增长的联立互动关系.本文采用三阶段最小二乘法(3SLS)估计了中国地区经济增长与人力资本增长的联立模型,结果表明,人力资本积累存在自身收敛性,人力资本增长率与地区经济增长率存在同向变化特征;同时,人力资本水平对地区经济增长存在直接发散和间接收敛双重效应,欠发达地区较高的人力资本增长率是导致20世纪80年代地区经济增长收敛的一个重要因素.因此,加大欠发达地区的人力资本投入,促进人力资本积累,对于缩小地区间经济增长差异具有十分重要的意义. 相似文献
287.
汤吉军 《中国人口.资源与环境》2009,19(6)
本文区分了确定性和不确定性条件下生态环境资源的定价与补偿机制的关系.在不确定性条件下,生态环境资源有不可逆性,往往会产生沉淀成本,由此产生期权价值,难以依靠传统的边际成本定价实现生态环境资源补偿,往往造成资源投资补偿不足.如果生态环境资源具有完全可逆性,那么就不会存在资源破坏和环境恶化问题.正是由于生态资源环境具有显著的不可逆性,沉淀成本普遍存在,特别是在未来不确定性的条件下,需要考虑期权价值对生态环境资源定价的影响,从而发现资源定价的根本原则在于生态环境资源价格中需要包括期权价值,特别是资源消耗导致未来资源消耗的减少.否则,由于期权价值没有进入生态环境资源价格里,很容易造成过度或掠夺开采生态资源.因此,合理的生态环境资源定价是建立生态环境资源补偿机制最根本的制度保障,也是市场完善的重要体现. 相似文献
288.
This paper analyzes livelihood change and livelihood sustainability of households in the upland part of the Lembang subwatershed,
West Sumatra, in response to changes in the natural resource management context during the last decade. Using the sustainable
livelihood framework (SLF), we measured livelihood changes at two separate points in time, 1996 and 2006, and assessed their
environmental, economic, social, and institutional sustainability. We found that people with a low income had less access
to capital assets than people from middle- and high-income groups. Our analysis revealed, however, that access to capital
assets increased over time, and that poor households experienced economic improvement, indicating an overall increase in economic
sustainability. Environmental sustainability, however, is threatened by intensive agricultural practices such as high agrochemical
input and intensive soil tillage on steep slopes, leading to pollution and soil erosion. Social sustainability is also a matter
of concern: while social exclusion has been reduced, income inequity has increased. Institutional sustainability is likely
to remain uncertain, as local institutions for natural resource management are still weak, despite the fact that decentralization
has been implemented during the last 8 years. External facilitation is needed to improve the livelihood of upland people while,
at the same time, enhancing the sustainability of watershed management. Strengthening local institutions, conserving natural
resources, and promoting environmentally sound agricultural practices are the three most important policies to be promoted
within the watershed. 相似文献
289.
This paper examines almost 30 years of disputation concerning the disposal of the world's largest stockpile of the toxic organochlorine, hexachlorbenzene. It describes the study of a chemicals company in its attempt to manage the disposal of the toxic waste in a collaborative fashion with government, environmentalists and the local community. The study describes the new processes and structures specifically designed to address the decision-making and the issues of stakeholder perception and identity construction which have influenced the outcomes. Decision-making in such disputes is often theorized from the perspective of the emergence of highly individualized and reflexive risk communities and changing modes and expectations of corporate responsibility as a result of detraditionalization. We argue that the stakeholder interaction in this study reflects competing discourses in which corporate actors prioritize the building and maintaining of identity and symbolic capital rather than an active collaboration to solve the ongoing issue of the waste. As well, issues of access to expert knowledge highlight the relationship between conditions of uncertainty, technoscientific expertise and identity. The events of the study highlight the challenges faced by contemporary technoscientific corporations such as chemicals companies as they must deliver on requirements of transparency and openness, while maintaining technoscientific capacity and strong internal identity. We conclude that the study demonstrates the co-existence of social processes of individualization and detraditionalization with quasi-traditions which maintain authority, thus challenging the radical distinctions made in the literature between modernity and late or reflexive modernity. 相似文献
290.
This article develops a dynamic model of efficient use of exhaustible marine sand resources in the context of marine mining externalities. The classical Hotelling extraction model is applied to sand mining in Ongjin, Korea and extended to include the estimated marginal external costs that mining imposes on marine fisheries. The socially efficient sand extraction plan is compared with the extraction paths suggested by scientific research. If marginal environmental costs are correctly estimated, the developed efficient extraction plan considering the resource rent may increase the social welfare and reduce the conflicts among the marine sand resource users. The empirical results are interpreted with an emphasis on guidelines for coastal resource management policy. 相似文献