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1.
In recent years, important changes have occurred in water resources research. There have been major shifts in attitudes of Congress, state legislatures and the general public toward water and related resource issues. Future water research and development will have to be environmentally oriented. Emphasis is shifting to research productivity. To justify research expenditures, hard facts must be produced which demonstrate payoff. Technology transfer (getting research results into the hands of users in an understandable and usable form) is gaining prominence. Research projects must be designed for total problem solution and technology transfer must be incorporated as a part of project objectives. Research must be planned and conducted to meet users' needs. Guidelines for modern research design and technology transfer are presented.  相似文献   

2.
This paper uses simulations of a model of a company's decision about the maximum bid value and the optimal investment programme for a resource tract to compare the auction and discretionary systems of licence allocation. The modle includes uncertainty about the size of resource stock and the selling price of extracted resource, as well as risk aversion on the part of the company. It is concluded that an auction system provides the government both with better information about a company's perception of the value of a resource tract and with the potential for considerably higher revenue from its licensing.  相似文献   

3.
In this paper, a procedure for analyzing a water resource system with special emphasis on evaluation of acceptable economic risk due to occasional failures to deliver water is proposed. The basic methodology includes the development of a simple mathematical model which describes the physical hydrologic and economic characteristics of a single reservoir irrigation and city water supply system and an evaluation of economic benefits of the system with full and partial deliveries of water. The system is simulated for various combinations of decision variables (system magnitudes) and an optimum design is obtained by response surface technology. Emphasis is placed on the basic model and methodology although, in order to introduce some realism, the procedure is applied to data based on the existing reservoir system on the South Concho River in West Central Texas.  相似文献   

4.
Allocating river recreation use to commercial and private sectors on white water rivers has been highly controversial. How this process is implemented may affect not only the availability of recreation opportunities to individual users, but may also negatively impact the user's desire to escape from the pressures and stresses of everyday life. In a study of users of Idaho's Middle Fork of the Salmon River, an Even-Pool allotment technique was preferred over others by the commercial, private, and rejectee individuals sampled. A lottery technique for rationing private use permits was preferred by private users and rejectees, while commercial users preferred Advance Reservation. No relationship was found between the users' stress release/escape expectations and their preferences for the different allotment and rationing techniques studies. Such results suggest that river managers may have considerable latitude in selecting allocation techniques that do not adversely affect on-site recreation experiences.  相似文献   

5.
REALM (REsource ALlocation Model) is a generalised computer simulation package that models harvesting and bulk distribution of water resources within a water supply system. It is a modeling tool, which can be applied to develop specific water allocation models. Like other water resource simulation software tools, REALM uses mass-balance accounting at nodes, while the movement of water within carriers is subject to capacity constraints. It uses a fast network linear programming algorithm to optimise the water allocation within the network during each simulation time step, in accordance with user-defined operating rules. This paper describes the main features of REALM and provides potential users with an appreciation of its capabilities. In particular, it describes two case studies covering major urban and rural water supply systems. These case studies illustrate REALM's capabilities in the use of stochastically generated data in water supply planning and management, modelling of environmental flows, and assessing security of supply issues.  相似文献   

6.
基于大数据的水环境风险业务化评估与预警研究   总被引:1,自引:1,他引:0       下载免费PDF全文
随着生态环境大数据的不断建设,国家级、流域级和行政区级别的大数据中心相继产生。快速、高效地分析和利用实时产生、类型多样的环境大数据,提取环境大数据在风险评估与预警的价值,具有重要的意义,也充满挑战。本文基于环境大数据的数据特点和不同层次的组织管理特征以及环境风险评估预警的业务化需求,构建基于大数据的流域环境风险评估与预警技术及其业务化系统的体系、分析环境风险智能识别模式、研究环境风险高效模拟预测和评估的方法,并提出一套满足各级管理部门需求,高效利用环境大数据的多中心业务化系统。  相似文献   

7.
8.
Risk aversion and compliance in markets for pollution control   总被引:1,自引:1,他引:0  
This paper examines the effects of risk aversion on compliance choices in markets for pollution control. A firm's decision to be compliant or not is independent of its manager's risk preference. However, non-compliant firms with risk-averse managers will have lower violations than otherwise identical firms with risk-neutral managers. The violations of non-compliant firms with risk-averse managers are independent of differences in their profit functions and their initial allocations of permits if and only if their managers' utility functions exhibit constant absolute risk aversion. However, firm-level characteristics do impact violation choices when managers have coefficients of absolute risk aversion that are increasing or decreasing in profit levels. Finally, in the equilibrium of a market for emissions rights with widespread non-compliance, risk aversion is associated with higher permit prices, better environmental quality, and lower aggregate violations.  相似文献   

9.
The study used the hypothetical lottery-choice questions to measure risk aversion and a detailed survey collected data on input use, farm production and non-farm activities to specifically assess whether risk aversion, risk perceptions, and socioeconomic factors affect the risk management strategies of farm households in Northern Ghana. Risk aversion significantly increases crop diversification strategies of households but marginally reduces herbicide use by households. Market risk significantly increases the use of improved seed varieties and the application of inorganic fertiliser but reduces diversification into livestock production. Production risk largely increases diversification into livestock production. Farmers’ risk management strategies are affected by socioeconomic variables such as access to extension services, area cultivated, age and gender. Policy effort focused on building pliable on-farm crop related risk management strategies should aim at considering the risk aversion and the perception of market risk whilst those focused on livestock should focus on production risk.  相似文献   

10.
Environmental Quality Perception (EQP) is an important construct used to help to understand the relationship between people and the hospital environment. From a patient-centered care perspective, it is important that hospital design take into account the patients' (and other users') point of view. This paper presents the adaptation and validation of a measure of hospital EQP, the Perceived Hospital Environment Quality Indicators (PHEQIs; Fornara, Bonaiuto, & Bonnes, 2006), and seeks to confirm the factor structure of this construct in a different cultural context. Three scales, two focusing on physical environments and one evaluating the social environment, were completed by 562 users of four orthopedic units in Portuguese hospitals, two older and two recently built or renovated. To assess criterion validity, hospital physical environments were also objectively evaluated by two architects. Using a confirmatory factor analysis the three validation procedures produced acceptable fit indices in the final measurement models. Overall reliability values were satisfactory, as was the evidence for criterion validity. PHEQIs scales and factors correlated with global evaluation of the environment, supporting concurrent criterion validity; and predictive criterion validity was demonstrated given that users of older and newer hospitals differed significantly on the perception of quality of hospital EQP, and that high congruence between users' and experts' evaluations was found. Discriminant construct validity was supported, and some difficulties in showing convergent validity are discussed in terms of item formulation adequacy. Implications for research and practice are described.  相似文献   

11.
ABSTRACT A methodology for predicting the spatial and temporal levels of conservative water quality constituents within a multibasin water resource system is presented. Dissolved solids, sulfates, and chlorides are the constituents used during this investigation; however, any other conservative ion or mineral can be incorporated into the simulation model. The methodology is tested on the proposed Texas Water System. The water quality model, QNET-I, utilizes monthly canal and river flows and reservoir storage levels calculated by the Texas Water Development Board's systems simulation model. Discharge-concentration relationships are developed for each source of water in the system, including significant waste-water discharges. Reservoirs in the system are assumed to be completely mixed with respect to conservative constituents. A mass balance analysis is performed for each node and each month during the simulation period. The output from the water quality simulation is a table of the concentrations of the conservative water quality constituents at each demand point in the system and in each reservoir and canal for every month the system is in operation. The desired quality of the water at the demand locations is used to determine the economic utility of transporting and mixing water from various sources.  相似文献   

12.
ABSTRACT: Interpretation of ground water level changes in a developed aquifer usually relies on reference to some benchmark such as “predevelopment” ground water levels, changes from fall to fall and/or spring to spring, or to determination of maximum stress during the pumping season. The assumption is that ground water levels measured in the monitoring well accurately reflect the state of the ground water resource in terms of quantity in storage and the effects of local pumping. This assumption is questionable based on the patterns shown in continuous hydrographs of water levels in monitoring wells in Nebraska, and wells installed to determine vertical gradients. These hydrographs show clear evidence for vertical ground water gradients and recharge from overlying parts of the aquifer system to deeper zones in which production wells are screened. The classical concept of semi‐perched ground water, as described by Meinzer, is demonstrated by these hydrographs. The presence of semi‐perched ground water (Meinzer definition, there is no intervening unsaturated zone) invalidates the use of measured ground water levels in regional observation programs for detailed numerical management of the resource. Failure to recognize the Meinzer effect has led to faulty management. The best use of data from the observation well network would be for detection of trends and education unless it is clearly understood what is being measured.  相似文献   

13.
Water availability risk is a local issue best understood with watershed‐scale quantification of both withdrawal and consumptive demands in the context of available supply. Collectively, all water use sectors must identify, understand, and respond to this risk. A highly visual and computationally robust decision support tool, Water Prism, quantitatively explores mitigation responses to water risk on both a facility‐level and basin‐aggregated basis. Water Prism examines a basin water balance for a 40‐ to 60‐year planning horizon, distinguishes among water use sectors, and accounts for ecosystem water needs. The 2012 Texas State Water Plan was used to apply Water Prism to the Big Cypress‐Sulphur Basin (Texas). The case study showed Water Prism to be an accurate and convenient tool to provide fine‐scale understanding of water use in the context of available supply, evaluate multi‐sector combinations of conservation strategies, and quantify the effects of future demands and water availability. Analyses demonstrated water availability risks for rivers and reservoirs can vary within a basin and must be calculated independently, simulation of water balance conditions can help illuminate potential impacts of increasing demands, and scenario simulations can be used to evaluate relative conservation efficacy of different water resource management strategies for each sector. Based on case study findings, Water Prism can serve as a useful assessment tool for regional water planners.  相似文献   

14.
A chance-constrained linear programming model, which utilizes multiple linear decision rules and is useful for river basin planning, is used to evaluate the effects of risk and reliability on optimal reservoir design. Streamflow forecasts or predictions can be explicitly included in the linear program. The risk associated with the predictions is included in the model through the use of cumulative distribution functions (CDF) of streamflows which are conditioned on the predictions. A multiple-purpose reservoir on the Gunpowder River in Maryland is used to illustrate the effectiveness of the model. In order to provide the decision makers with complete and useful information, trade-off curves relating minimum reservoir capacity (a surrogate for dam costs), water supply and flood control targets, and the reliability of achieving the targets are developed. The trade-off curves may enhance the decision maker's ability to select the best dam capacity, considering technological and financial constraints as well as the trade-offs between targets, risks, and costs.  相似文献   

15.
ABSTRACT: An inverse‐simulation approach is used to determine optimal strategies for developing public water‐supply systems in a shallow, coastal aquifer on the outermost arm of the Cape Cod peninsula in Massachusetts. Typically a forward simulation (or “trial and error”) approach is used to find best pumping strategies, but the chances of finding success with this tact diminish as the number of potential options grows large. Well locations and pumping rates are optimized with respect to: (1) providing sufficient water to areas of water‐quality impairment, (2) minimizing impacts to nearby surface waters, (3) preventing saltwater contamination due to overpumping, and (4) minimizing financial cost of well development. Potential well sites and water‐supply scenarios are separated into “politically‐based” and “resource‐based” categories to gain insight into the degree that pre‐existing political boundaries hinder best management practices. The approach provides a promising tool in transboundary water‐resources settings because it allows stakeholders to find solutions that best meet everyone's goals, as opposed to pursuing options that will create conflict, or are less than optimal.  相似文献   

16.
A multicriteria analysis system was developed for producing risk maps of agricultural pollution due to alternative cultivation systems in the Watershed of the Lagoon of Venice (WLV) in Italy. Results of a field-scale simulation model for agricultural diffuse pollution were used to compile a matrix of environmental impacts, in terms of pollution indices. The most widespread combinations of typical environments (as defined by combinations of soil and climate variables) and alternative land uses (types of crops and cultivation systems) were described in the impact matrix. Land use in terms of crop distribution was based on census data. Two alternative cultivation systems were defined on the basis of the recent changes to the European Common Agricultural Policy: ordinary and eco-compatible. The effects of alternative scenarios were evaluated in terms of pollution risks for water resources. The evaluation procedure was built into the framework of a geographical information system to take into account the spatial features of pollution phenomena, vulnerability of the land and risk for water resources. The results demonstrated the great potential of eco-compatible practices for reducing the risks for surface and groundwater (−15 and −50%, respectively).  相似文献   

17.
A large number of mathematical models have been developed to support land resource allocation decisions and land management needs; however, few of them can address various uncertainties that exist in relation to many factors presented in such decisions (e.g., land resource availabilities, land demands, land-use patterns, and social demands, as well as ecological requirements). In this study, a multi-objective interval-stochastic land resource allocation model (MOISLAM) was developed for tackling uncertainty that presents as discrete intervals and/or probability distributions. The developed model improves upon the existing multi-objective programming and inexact optimization approaches. The MOISLAM not only considers economic factors, but also involves food security and eco-environmental constraints; it can, therefore, effectively reflect various interrelations among different aspects in a land resource management system. Moreover, the model can also help examine the reliability of satisfying (or the risk of violating) system constraints under uncertainty. In this study, the MOISLAM was applied to a real case of long-term urban land resource allocation planning in Suzhou, in the Yangtze River Delta of China. Interval solutions associated with different risk levels of constraint violation were obtained. The results are considered useful for generating a range of decision alternatives under various system conditions, and thus helping decision makers to identify a desirable land resource allocation strategy under uncertainty.  相似文献   

18.
This article examines the unfolding of integrated water resource management (IWRM) reforms in southwest Burkina Faso, where water resources are subject to conflicting claims by a diversity of users. We first describe the establishment a local water user committee, showing how choices regarding composition and operations grant varying levels of recognition to different stakeholders. We then discuss the implications for key dimensions of decentralized governance, namely representation and accountability. In particular we focus on: (a) how the interplay of political agendas and policy disconnects shapes the committee's viability and credibility and (b) how tensions between techno‐scientific and local knowledge affect participation and transparency. We argue that in contexts defined by contentious politics and neo‐patrimonial practices, representativeness is better ensured by the direct inclusion of user groups rather than elected officials. Though limited discretionary power, information access, and technical capabilities of committee members inhibit accountability, rural producers uphold their claims through social mobilization and reliance on local knowledge. Recognizing the opportunities offered by the country's recent democratic turn, we formulate recommendations aimed at addressing structural drivers and enabling citizen agency in decentralized water governance. At the same time, further research is needed on local people's understandings of representation and accountability, to ensure that they are involved in institutional design and practices in ways that affirm what they value and what they know.  相似文献   

19.
建设化工区需对企业进行合理规划布局,且化工区风险预警和防范具有优先性问题,需要对企业进行有效的风险分级。现有研究中的区域风险源分级方法上存在较大的不足。根据化工区风险源的特点,基于环境风险评价和灰色系统的基本理论,探索性的将灰色聚类分析方法应用于化工区风险源分级中。建立了一套适合化工园区的指标,对各个企业进行聚类分析,划分风险等级。以大连市某化工区为例,筛选8个指标,并选取了6个化工企业进行灰色聚类分析。将它们归为4个不同的风险级别。该方法不仅能较全面地反映化工区各个风险源的风险级别,对风险源的规划、布局和管理起到较好的决策支持作用,而且能指导预警和防范体系的建立,合理分配有限的资源。  相似文献   

20.
The Resource Management Act (RMA) legislates the management of most natural resources in New Zealand. The RMA invokes ecosystem-based management by requiring that regulation be based on managing the effects of resource according to “the life supporting capacity” of the environment. The management of water resources under the RMA is carried out at the regional level by regional councils. Regional councils can develop regional water plans to establish objectives and criteria for water management. Regional water planning under the RMA has been problematic, and regional plan objectives developed under the RMA have been criticized as too broad and not sufficiently quantified. As a consequence, many resource users are unconvinced of the need for the regulatory criteria promulgated by plans, whereas other groups are concerned that the environment is inadequately protected. This article proposes that a lack of ecologically relevant management units has prevented regional water plans from fulfilling their intended function under the RMA. Then it introduces the use of River Environment Classification as a means of defining units for assessment and management, and provides three case studies that demonstrate its potential to support regional water management planning. The discussion shows that the specificity of regional assessments can be increased if ecologic variation is stratified into distinctive units (i.e., units within which variation in the characteristics of interest is reduced) as part of the assessment process. The increased specificity of the assessments increases the possibility that regional objectives and criteria for water management can be derived that are quantitative and justifiable and that provide certainty for stakeholders. The authors conclude that greater choice and meaning can be generated in regional planning processes if regional variation in ecologic characteristics is stratified using a classification, and if classes are used as units for assessment and management.  相似文献   

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