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491.
广东自然灾害成因及其对经济的影响 总被引:8,自引:0,他引:8
本文从地理位置、地形特征、地质构造、水文特征、天气气候特征、人类活动、经济结构与布局,以及社会环境等8个方面分析了广东自然灾害形成的环境条件及类型,并分析研究了成灾特点和对广东经济发展的影响。结果表明,广东自然灾害的形成及其成灾频度和强度,既决定于自然环境的变异,也受制于人类活动和社会经济环境,并具有区域性、周期性、群发性、连锁性、阶段性和社会性等特点,自然灾害对于广东经济发展的严重影响有日益加剧的趋势。 相似文献
492.
灾害经济损失的空间特征指标及其计算 总被引:4,自引:0,他引:4
本文将灾害的经济损失划分为财产损失、救灾费用和效益损失;将每种经济损失按其空间特征划分为内部经济损失和外部经济损失;提出了各种内部经济损失、外部经济损失的计算内容和计算方法;还对几个概念性问题进行了讨论. 相似文献
493.
494.
Keith Hayton 《Journal of Environmental Planning and Management》1989,32(2):115-120
In the past much of the training effort of public agencies was not aimed at specific job vacancies or at areas of skill shortages. In contrast, targeted training aims to provide identified disadvantaged groups with training to enable them to compete for identified job vacancies. This paper looks at the success of targeted training through three examples, at how its effectiveness can be improved, and the role of local government in initiating and developing such training. 相似文献
495.
The paper is concerned with the impact of small business advice agencies on their clients. The work of two agencies (an Enterprise Agency and a local authority Development Unit) operating in the same geographical area (Swale in Kent) is evaluated using a survey of clients as evidence. It is concluded that both agencies are meeting real and distinctive needs among start‐up and established small businesses in the area, and have established effective systems for the delivery of their services. Quality of staff is confirmed as a key factor influencing client satisfaction with the agencies. The impact of the agencies on busines efficiency is ambiguous; it is suggested that major beneficiaries of the work of the agencies are the banks. 相似文献
496.
Sean Montgomery 《Journal of Environmental Planning and Management》1986,29(2):74-79
Saudi Arabia has undergone revolutionary change to its economy since 1973, followed more recently by serious economic problems. The largely peripheral effects of urban planning upon the transformation of Jeddah from medieval town to international city are considered. The main urban problems and opportunities facing the city are identified, and the paper concludes with a question against the relevance of ‘Western’ notions of planning to another culture undergoing dynamic urban change. 相似文献
497.
Alan Richardson 《Journal of Environmental Planning and Management》1985,28(2):60-65
Traditional economic planning policies do not, largely, benefit residents of run‐down inner city neighbourhoods. Planners have therefore begun to look at other ways to improve the economic well‐being of unemployed people in such areas. One such initiative has been the location of Community Employment Development Officers in economically depressed areas by Cleveland County Council — one of Britain's unemployment blackspots. Their remit is to encourage and initiate action to create jobs and this paper looks at the experiment, drawing out some of the lessons. 相似文献
498.
D'Souza F 《Disasters》1986,10(1):35-52
This paper is the result of a social and economic survey of four villages in the Gediz region of South West Anatolia, Turkey, which was undertaken in two phases, October/November 1982 and March/April 1984. The specific aims of this survey were to define what was perceived as recovery in the local social, cultural and economic context and to measure recovery in communities which had suffered different degrees of distress and loss following the earthquake and, consequently, had received different amounts and kinds of assistance from the government. Essentially, therefore, the survey sought to answer the question – how far did the government programme of assistance promote recovery and over what period of time? The implications of such an inquiry concern what constitutes appropriate assistance following earthquake in rural communities. It is hoped that studies of this kind can help to guide decision making of both national governments and international humanitarian organizations on the role of material aid in the process of recovery. This is particularly urgent in view of the fact that preliminary investigations of other small rural and under-developed communities struck by earthquake suggest that material aid may actually preclude recovery in the longer term. 相似文献
499.
Reliability of Absolute and Relative Predictions of Population Persistence Based on Time Series 总被引:4,自引:0,他引:4
Abstract: Conventional population viability analysis (PVA) is often impractical because data are scarce for many threatened species. For this reason, simple count-based models are being advocated. The simplest of these models requires nothing more than a time series of abundance estimates, from which variance and autocorrelation in growth rate are estimated and predictions of population persistence are generated. What remains unclear, however, is how many years of data are needed to generate reliable estimates of these parameters and hence reliable predictions of persistence. By analyzing published and simulated time series, we show that several decades of data are needed. Predictions based on short time series were very unreliable mainly because limited data yielded biased, unreliable estimates of variance in growth rate, especially when growth rate was strongly autocorrelated. More optimistically, our results suggest that count-based PVA is sometimes useful for relative risk assessment (i.e., for ranking populations by extinction risk), even when time series are only a decade long. However, some conditions consistently lead to backward rankings. We explored the limited conditions under which simple count-based PVA may be useful for relative risk assessment. 相似文献
500.
Effects of Road Fencing on Population Persistence 总被引:6,自引:0,他引:6
Abstract: Roads affect animal populations in three adverse ways. They act as barriers to movement, enhance mortality due to collisions with vehicles, and reduce the amount and quality of habitat. Putting fences along roads removes the problem of road mortality but increases the barrier effect. We studied this trade-off through a stochastic, spatially explicit, individual-based model of population dynamics. We investigated the conditions under which fences reduce the impact of roads on population persistence. Our results showed that a fence may or may not reduce the effect of the road on population persistence, depending on the degree of road avoidance by the animal and the probability that an animal that enters the road is killed by a vehicle. Our model predicted a lower value of traffic mortality below which a fence was always harmful and an upper value of traffic mortality above which a fence was always beneficial. Between these two values the suitability of fences depended on the degree of road avoidance. Fences were more likely to be beneficial the lower the degree of road avoidance and the higher the probability of an animal being killed on the road. We recommend the use of fences when traffic is so high that animals almost never succeed in their attempts to cross the road or the population of the species of concern is declining and high traffic mortality is known to contribute to the decline. We discourage the use of fences when population size is stable or increasing or if the animals need access to resources on both sides of the road, unless fences are used in combination with wildlife crossing structures. In many cases, the use of fences may be beneficial as an interim measure until more permanent measures are implemented. 相似文献