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1.
This study employs a benefit-cost analysis framework to estimate market and non-market benefits and costs of controlling future spruce budworm (Choristoneura fumiferana) outbreaks on Crown forest lands in New Brunswick, Canada. We used: (i) an advanced timber supply model to project potential timber volume saved, timber value benefits, and costs of pest control efforts; and (ii) a recent contingent valuation method analysis that evaluated non-market benefits (i.e., changes in recreation opportunities and existence values) of controlling future spruce budworm outbreaks in the Province. A total of six alternative scenarios were evaluated, including two uncontrolled future budworm outbreak severities (moderate vs. severe) and, for each severity, three control program levels (protecting 10%, 20%, or 40% of the susceptible Crown land forest area). The economic criteria used to evaluate each scenario included benefit-cost ratios and net present values. Under severe outbreak conditions, results indicated that the highest benefit-cost ratio (4.04) occurred when protecting 10% (284,000 ha) of the susceptible area, and the highest net present value ($111 M) occurred when protecting 20% (568,000 ha) of the susceptible area. Under moderate outbreak conditions, the highest benefit-cost ratio (3.24) and net present value ($58.7 M) occurred when protecting 10% (284,000 ha) of the susceptible area. Inclusion of non-market values generally increased the benefit-cost ratios and net present values of the control programs, and in some cases, led to higher levels of control being supported. Results of this study highlight the importance of including non-market values into the decision making process of forest pest management.  相似文献   

2.
ABSTRACT: Hydrologic and economic information must be integrated in flood plain management. This study describes an integrated approach which includes consideration of the hydrologic, hydrodynamic, physical, and economic components of the total system. On the basis of these components, a theoretical model is proposed which provides a rational procedure for estimating flood damages from projections of economic development within an area. The utility of the model is demonstrated by applying it to a flood-prone region in Southern Quebec, Canada.  相似文献   

3.
ABSTRACT: This paper presents a new methodology to calculate economic losses from hypothetical, extreme flood events, such as the Probable Maximum Flood. The methodology uses economic data compiled from already-available secondary sources, such as U.S. Census data on magnetic tapes, utilizing microcomputer and other electronic media. Estimates of land elevations are obtained from topographic maps, and flood elevations axe estimated using, for example, a dam breach and flood routing (DAMBRK) model (Fread, 1984). The calculations are performed at a disaggregate spatial scale, by various land use and industrial classification categories. The basic areal units are city blocks (for urbanized areas), enumeration districts, and Census tracts. Depth-damage functions, which provide an estimate of damages as a proportion of the existing value of the structure, are estimated statistically. Computer software (called DAMAGE) is used to combine the economic, flood elevation, and depth-damage information to compute economic losses for different possible flood stages and for different inflow events. Two case studies are presented as illustrations of the method.  相似文献   

4.
ABSTRACT: The distribution of costs and benefits among groups in society of alternative flood management actions is examined in terms of their final incidence or resting place-their influence on real estate values. The alternatives examined include structures, disaster relief, floodproofing, watershed land treatment, floodplain zoning, and flood insurance. The impact of each alternative on the amount of flood disability cost paid by the landowner is examined and variations among alternatives are used to explain the past political success of structures and relief as compared to zoning, floodproofing, and insurance.  相似文献   

5.
ABSTRACT: A retrospective benefit-cost analysis of major water resources projects in the Cumberland River basin was conducted. The U.S. Army Corps of Engineers' projects selected were Dale Hollow, Wolf Creek, Center Hill, and J. Percy Priest Reservoirs. The ex-post performance of the evaluated reservoirs were compared to the ex-ante estimates. Benefits and costs for each project were deflated to their base year and respective average annual values for each of these components were calculated. An ex-post benefit-cost ratio was determined for each project, as well as the combined system. The benefit-cost ratio for each project surpassed unity. The actual ratio as compared to the ex-ante estimate for each project is as follows: Dale Hollow, 1.24 to 1.46; Wolf Creek, 1.40 to 1.53; Center Hill, 1.17 to 2.02; and J. Percy Priest, 1.45 to 1.6. The internal rate of return was also determined for each project. The results obtained for each project are tabulated and discussed with consideration given to factors effecting the economic evaluation of the projects.  相似文献   

6.
ABSTRACT. In the last decade much research has been devoted to applying the systems analysis approach to water resources problems. A popular research goal has been determination of the “best” method of operating a multipurpose reservoir. The goal of this study was to derive the economically optimum flood control diagram for a multipurpose reservoir by systems analysis. The technique employed to optimize the flood control diagram was programmed so that the optimization process could be applied to other multipurpose reservoirs. Two computer programs developed at the U.S. Army Corps of Engineers' Hydrologic Engineering Center were utilized with modifications to simulate the operation of Folsom Reservoir in central California. Economic analyses were incorporated along with an optimization technique into the reservoir operations program; and the resultant program was capable of routing a sequence of monthly reservoir inflows, computing benefits for various flood control diagrams (as dictated by the optimization procedure), and selecting the economically optimum flood control diagram. The univariate gradient technique was the optimization procedure employed. The two computer programs are on file at the Hydrologic Engineering Center in Davis, California.  相似文献   

7.
HEC1F is a computer program for making short- to medium-term forecasts of uncontrolled flood runoff. The program employs unit hydrographs and hydrologic routing to simulate runoff from a subdivided basin. Estimates of future rainfall can be accommodated. Runoff parameters for gaged headwater subbasins can be estimated (optimized) in real time. Blending of calculated with observed hydrographs can be performed. HEC1F is a component of an on-line software system that includes capability for data acquisition and processing, precipitation analysis, streamflow forecasting, reservoir system analysis, and graphical display of data and simulation results. The conceptual framework for HEC1F is described, and application of the program is illustrated.  相似文献   

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10.
ABSTRACT: Bayesian and non-Bayesian flood levee design methods that account for the uncertainty due to limited record length are compared using a case study. The first method, Bayesian decision theory (BDT), imbeds the uncertainty in the parameters of the yearly peak stage into a loss function. The optimum design of the flood levee, called Bayes design, corresponds to the minimum expected loss, called Bayes risk. The second method, induced safety algorithm (ISA), computes a margin of safety to be added to either an existing levee or a levee designed by classical benefit-cost analysis. The design decision is shown to fluctuate as different record lengths are considered. For short record lengths, BDT, which takes small sample bias into account, appears to yield a more conservative design than ISA. On the other hand, ISA, which is simple to implement, seems to be preferable to BDT for longer record lengths.  相似文献   

11.
A ground water development project in the northern part of Thailand was appraised by means of benefit-cost analysis. This is the first project in Thailand to develop ground water for irrigation purposes and it is also the first project which made use of an underground PVC pipe water distribution system. Results indicate that the project is economically feasible. In comparing different water distribution systems, it is also found that distribution by means of underground PVC pipes is more economical compared to an open ditch system if the life of the latter is relatively short and the rates of inflation are high.  相似文献   

12.
Information about the net benefits of land degradation treatment is required at the relevant management level, such as regional, local or site-specific, to assist decision makers in the allocation of funds to soil conservation. In this paper, estimates of regional opportunity costs of erosion and costs of treatment are used to derive benefit-cost ratios to assess the profitability of gully erosion treatment for localities in the wheat-sheep zone of New South Wales. These results are then used to develop site-specific models which predict benefit-cost ratios of treatment from land attributes including gully length, slope, soil type and land use. These predictive models form the basis of a rapid appraisal method to aid soil conservation decisions.  相似文献   

13.
ABSTRACT: In conventional flood damage reduction studies, flood damage is usually estimated with a damage function according to the depth of inundation. However, this method may not reflect the conditions of each family residing in the floodplain because it ignores not only the distribution of flood damage but also the effect of building characteristics and residents' preparedness. This paper uses data from a questionnaire based survey (N= 3,036) conducted 17 months after the Tokai Flood of 2000 that caused disastrous losses to household properties. It provides a conceptual “doughnut structure” model of flood damage to houses and house contents and a mathematical basis for models to explore the determinants of flood damage. Besides the inundation depth, house type significantly affects both the house structural and content damage probabilities, while house ownership and house structure affect house damage probability but not house content damage probability at a given depth. Inundation depth, residing period, and household income significantly affect both house and content damage values. In addition, house ownership has a significant impact on the house damage value, while house structure has an impact on content damage value.  相似文献   

14.
ABSTRACT: The project described in this report was undertaken by the Louisiana State Planning Office to establish the extent of backwater flooding in Louisiana in April 1975. Band 7 Landsat imagery, enlarged to a scale of 1:250,000 was used to visually identify flooded areas. Inundated areas were delineated on overlays keyed to 1:250,000 U.S. Geological Survey topographic quadrangles. Tabular data identifying acres flooded, according to land use type, were derived by merging the flood map overlays with computerized 1972 land use data. Approximately 1.12 million acres of the state were inundated by flood waters. The total acreage and land use types affected by flooding were determined within 72 hours from the time the flood areas were imaged. Flooded maps were prepared for 26 parishes. Field observations were made by Louisiana Cooperative Extension Service county agents in order to determine the accuracy of parish flood maps and flood acreage figures by land use type. Results indicated that this was a fast, accurate, and relatively inexpensive method of compiling flood data for disaster planning and postflood analysis.  相似文献   

15.
ABSTRACT: The accurate and reliable determination of floodplains, floodway boundaries, and flood water elevations are integral requirements of Flood Insurance Studies. These studies are intended to be used for determining the flood insurance rates. Therefore, the accuracy of the water surface profiles are important. To ensure the high degree of accuracy, the HUD Flood Insurance Administration has developed standards which must be met in the analysis of water surface profiles. A somewhat less accurate study is required for the preparation of Flood Emergency Plans. As part of the flood insurance studies of eight locations in the State of North Dakota, various flood hazard and floodplain information reports were reviewed. The hydrologic and hydraulic analyses, especially the computation of the 100-year water surface profiles, were completed using both simplified and complex hydraulic computation methods. Significant differences were found (1 to 3 feet) between the profiles computed by the SCS simplified method and those computed by HEC-2 computer program. However, the floodplain boundaries determined by both methods were found to be similar. Approximate methods are recommended for rapid determination of the floodplain, floodway boundaries, and inundation area mapping, while sophisticated computer programs (HEC-2) are recommended to be used for developing areas where the 100-year flood elevation has a significant impact on the cost of land development.  相似文献   

16.
ABSTRACT: The main purpose of this study is to evaluate the management practice effects on Ming-Hu and Ming-Tan reservoir watersheds during the past 15 years. It is difficult to economically evaluate a watershed project consisting of a number of multisectoral and long term management practices and regulations. However, the reservoirs’ hydropower operations and their associated benefits and costs are highlighted in this study. The estimated management practice value (net present value) of 351 million NT (New Taiwan) dollars and a benefit-cost ratio of 1.189 are obtained for the Ming-Hu subwatershed. Because the Ming-Tan hydropower station only began commercial operation in 1992 the estimated management practice value is negative 103 million NT dollars (net present value) and the benefit-cost ratio is 0.653 in the Ming-Tan subwatershed. If the analysis period is contained to the year 2010, the benefit-cost ratio of Ming-Tan reservoir subwatershed becomes 1.103. Ming-Hu and Ming-Tan subwatersheds together share the benefit-cost ratio of 1.182 and the net present value of 1,589 million NT dollars. The results of the analyses indicate that the Taiwan Power Company, the watershed management agency, has implemented economically efficient watershed practices and regulations in Ming-Hu and Ming-Tan reservoir watersheds and the watershed management practices are worthwhile and should be sustained.  相似文献   

17.
Results of the establishment of a Local Flood Relations program in 1953 by TVA are discussed. In 16 years TVA has produced local floodplain information reports for 126 communities. As of September 1, 1969, 66 valley communities had adopted floodplain provisions in their zoning ordinances or subdivision regulations, or both. The local-state-Federal team approach to floodplain management is viable and any other appears to be doomed to failure. A floodplain management program can be expected to succeed as a collaborative effort at all levels of government, each playing the part and assuming the responsibilities best fitted to it. Most of us now accept that our flood problems will not be solved by engineering works alone or even in combination with upstream land management. The solution requires a linking of broad community planning with traditional engineering works. This means that the local, state, and Federal objectives and policies must be effectively coordinated. This method has been developed and satisfactorily applied in the Tennessee Valley during the past decade. The need for more effective means for coping with mounting local flood losses was recognized by the Tennessee Valley Authority and led to the establishment of its Local Flood Relations program in 1953. Since a working relationship with the people of the Valley and their state and local institutions had been carefully nurtured by TVA for over twenty years, it was only natural that the new program would also be a cooperative one.  相似文献   

18.
Oregons land-use planning program is often cited as an exemplary approach to forest and farmland conservation, but analyses of its effectiveness are limited. This article examines Oregons land-use planning program using detailed spatial data describing building densities in western Oregon. An empirical model describes changes in building densities on forest and agricultural lands from 1974 to 1994, as a function of a gravity index of lands commuting distance to cities of various sizes, topographic characteristics, and zoning adopted under Oregons land-use planning program. The effectiveness of Oregons land-use planning program is evaluated based on the statistical significance of zoning variables and by computing estimated areas of forest and agricultural lands falling into undeveloped, low-density developed, and developed building density categories, with and without land-use zoning in effect. Results suggest that Oregons land-use planning program has provided a measurable degree of protection to forest and agricultural lands since its implementation.  相似文献   

19.
Flooding and the susceptibility to flood damage inherent in all land uses constitute the flood hazard. Resolution of the hazard while properly recognizing flood plain environmental attributes within the context of overall community or area needs is the essence of comprehensive flood plain management. The traditional approach–flood control–has effected modification of only the flooding component of the hazard whether it be coastal or inland. Until recently Federal programs have overlooked the possibilities of modifying the susceptibility component, for which the major responsibility lies with non-Federal interests. Beginning with actions in the TVA area, the latter is now being strongly encouraged through Federal programs and actions notably the Flood Plain Management Services and Survey Programs of the Corps of Engineers, those stemming from Executive Order 11296, and those required for eligibility under the National Flood Insurance Act of 1968. Flood plain management objectives must be stated in planning, e.g., economic efficiency, reduction in threat to life and health, environmental improvement, and regional development, to permit proper evaluation of the optional means and approaches for achieving them.  相似文献   

20.
肖国权  张钊 《四川环境》1993,12(4):64-66
本文对大巴山区农业生产中用化学药剂防治状况及存在的主要问题进行了分析研究。在此基础上,提出开展农药区划和区域性宏观调控,建立农药污染监测管理机制,进一步提高综合防治技术水平和专业化防治程度,加强防止污染微观技术的研究与推广控制策略和措施,以实现对化学药剂防治与农业生态环境保护。把农业环境保护工作纳入农业发展和国家农业环境保护的总体规划。  相似文献   

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