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31.
Downing TE 《Disasters》1990,14(3):204-229
The geographic and temporal scale of institutional responses to food crises suggests three levels of food information or famine early warning system: a seasonal national food balance, baseline data on household food poverty and estimates of vulnerability to climatic and economic variations, and targeted interventions based on individual entitlements and food deprivation. Stimulating the demand for food information, beyond the need to forecast famines, is a crucial factor in the adoption of improved monitoring systems. Issues in the design of food information systems are illustrated by the experience in Kenya in 1984–85. The government of Kenya responded to the 1984 drought and ensuing food crisis to prevent widespread famine, largely through timely commercial imports of yellow maize. Although qualified by the nature of the drought and Kenya's economic development, this success story emphasises the need to improve food information systems.  相似文献   
32.
ABSTRACT. The article proposes the use of certain water and sewer extension pricing and investment policies. Such policies would complement an urban growth policy designed to guide the location and timing of growth in urbanizing areas. Proposed pricing policies are based upon marginal cost principles. The types of pricing policies discussed include benefit assessments, connection fees, and user charges. Proposed investment policies deal with the division of financing responsiblities between the public and private sectors. Discussion of each proposal explains the economic influence of the proposed policies upon key decision makers in the land development process. The application of proposed pricing and investment policies in the case study communities is mixed. In Knoxville, Tennessee, where pricing and investment policies reflect the proposed policies, no urban growth policy exists. In Lexington, Kentucky, mixed pricing and investment policies do not complement what is a relatively good urban growth policy. In Greensboro, North Carolina, reasonably effective pricing and investment policies complement other policies which provide some guidance to the urban growth pattern. It is hoped that the article will increase the recognition of utility pricing and investment policies as one means of implementing urban growth policy.  相似文献   
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34.
This paper introduces broad concepts of vulnerability, food security and famine. It argues that the concepts and theories driving development and implementation of vulnerability assessment tools are related to their utility. The review concludes that socio-geographic scale is a key issue, and challenge. It analyses three vulnerability assessment (VA) methods, using Ethiopia as a case study. Facing the challenges of vulnerability assessment and early warning requires providing accurate information at the required scale, useful for multiple decision-makers within realistic institutional capacities.  相似文献   
35.
Agent-based integrated assessment modelling: the example of climate change   总被引:1,自引:0,他引:1  
Current approaches to deal with the socio-economic implications of climate change rely heavily on economic models that compare costs and benefits of different measures. We show that the theoretical foundations underpinning current approaches to economic modelling of climate change are inappropriate for the type of questions that are being asked. We argue therefore that another tradition of modelling, social simulation, is more appropriate in dealing with the complex environmental problems we face today.  相似文献   
36.
The intersection of present vulnerability and the prospect of climate change in Africa warrants proactive action now to reduce the risk of large-scale, adverse impacts. The process of planning adaptive strategies requires a systematic evaluation of priorities and constraints, and the involvement of stakeholders. An overview of climate change in Africa and case studies of impacts for agriculture and water underlie discussion of a typology of adaptive responses that may be most effective for different stakeholders. The most effective strategies are likely to be to reduce present vulnerability and to enhance a broad spectrum of capacity in responding to environmental, resource and economic perturbations. In some cases, such as design of water systems, an added risk factor should be considered.  相似文献   
37.
J. A. Downing 《Marine Biology》1989,103(2):231-234
Normative variance functions can be used to accurately predict sampling exigencies, but such empirically derived formulae are continuous functions that can predict levels of sampling precision that cannot logically occur in discrete population samples. General formulae are presented that allow calculation of upper and lower boundary constraints on levels of sampling precision. These boundary constraints would only have a significant influence on sampling design where populations are so sparse that samples consist mainly of presence-absence data. A previously published empirical equation for the prediction of requisite sample number for the estimation of a freshwater benthos population correctly shows that using a small sampler can result in an up to 50-fold reduction in the amount of sediment processed, regardless of these constraints. A previously published empirical equation for the prediction of sampling variance, based on over 3000 sets of replicate samples of marine benthos populations, suggests that the use of small samplers over large ones requires the processing of between one-half and one-twentieth of the sediment for the same level of precision. It is concluded that discussions of sampling optimization should be based on knowledge of real sampling costs.  相似文献   
38.
This study was conducted to determine the main sources of dissolved organic carbon (DOC) and disinfection byproduct (DBP) precursors to the McKenzie River, Oregon (USA). Water samples collected from the mainstem, tributaries, and reservoir outflows were analyzed for DOC concentration and DBP formation potentials (trihalomethanes [THMFPs] and haloacetic acids [HAAFPs]). In addition, optical properties (absorbance and fluorescence) of dissolved organic matter (DOM) were measured to provide insight into DOM composition and assess whether optical properties are useful proxies for DOC and DBP precursor concentrations. Optical properties indicative of composition suggest that DOM in the McKenzie River mainstem was primarily allochthonous--derived from soils and plant material in the upstream watershed. Downstream tributaries had higher DOC concentrations than mainstem sites (1.6 +/- 0.4 vs. 0.7 +/- 0.3 mg L(-1)) but comprised < 5% ofmainstem flows and had minimal effect on overall DBP precursor loads. Water exiting two large upstream reservoirs also had higher DOC concentrations than the mainstem site upstream of the reservoirs, but optical data did not support in situ algal production as a source of the added DOC during the study. Results suggest that the first major rain event in the fall contributes DOM with high DBP precursor content. Although there was interference in the absorbance spectra in downstream tributary samples, fluorescence data were strongly correlated to DOC concentration (R2 = 0.98), THMFP (R2 = 0.98), and HAAFP (R2 = 0.96). These results highlight the value of using optical measurements for identifying the concentration and sources of DBP precursors in watersheds, which will help drinking water utilities improve source water monitoring and management programs.  相似文献   
39.
The body of information presented in this paper is directed to those individuals concerned with cost-effective enforcement of environmental standards. Its aim is twofold. One is to determine some of the differing impacts upon firm behavior of legal enforcement, of economic incentive enforcement, and of mixed legal-economic enforcement. A second objective is to initiate identification of enforcement systems which are most likely to minimize resource costs to firms and enforcement agencies of meeting environmental standards. A computerized model is used to simulate enforcement of the new source particu-late matter discharge standard for coal-fired power plants. Under current legal enforcement it is found that most plants will violate the standard, that small plants will control to higher removal levels than large plants and that firms will install relatively costly pollution control technology. Three enforcement alternatives are considered for overcoming these shortcomings: more stringent legal enforcement, economic incentive enforcement using effluent taxes, and a mixed system which uses device certification tests and effluent taxes. It is found that each of the alternatives can lead to the standard being met and tc more-or-less equal sharing in control burden across plant size. But it is only the two systems which use effluent taxes that give incentive for choosing least costly control technology. It is concluded that the two enforcement systems which use effluent taxes probably would encourage adoption of least cost control technology. This is likely to be a desirable outcome since it may lead to minimum resource costs to power plants and pollution control agencies of meeting fty ash standards. The general applicability of this conclusion to other enforcement situations is discussed.  相似文献   
40.
Over the past few decades, four distinct and largely independent research and policy communities--disaster risk reduction, climate change adaptation, environmental management and poverty reduction--have been actively engaged in reducing socio-economic vulnerability to natural hazards. However, despite the significant efforts of these communities, the vulnerability of many individuals and communities to natural hazards continues to increase considerably. In particular, it is hydro-meteorological hazards that affect an increasing number of people and cause increasingly large economic losses. Arising from the realisation that these four communities have been largely working in isolation and enjoyed only limited success in reducing vulnerability, there is an emerging perceived need to strengthen significantly collaboration and to facilitate learning and information exchange between them. This article examines key communalities and differences between the climate change adaptation and disaster risk reduction communities, and proposes three exercises that would help to structure a multi-community dialogue and learning process.  相似文献   
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