基于动态随机前沿生产函数的工业用水边际效益研究

将水资源作为生产要素,通过基于面向输出的C2GS2模型DEA相对有效性评价,建立有效生产前沿,分析产出的技术效率和生产要素的使用效率.利用具有积性误差的Hicks中性技术进步Cobb-Douglas生产函数,通过有效生产前沿时间序列数据COLS回归,建立动态随机前沿生产函数.利用序列数据建立序列与截面水资源边际效益模型...     

基于动态随机前沿生产函数的水资源边际效益研究

将水资源作为生产要素,通过基于面向输出的C^2GS^2模型DEA相对有效性评价,建立有效生产前沿,分析产出的技术效率和生产要素的使用效率。利用具有积性误差的Hicks中性技术进步Cobb--Douglas生产函数,通过有效生产前沿时间序列数据COLS回归,建立动态随机前沿生产函数。利用序列数据建立序列与截面水资源边际效益模型、缺水损失模型及序列节水边际成本模型。     

Residential Water Use: Efficiency, Affordability, and Price Elasticity

In practice, water pricing is the main economic instrument used to discourage the wasteful use of residential water. Owing to considerations of affordability, residential water is systematically underpriced because water is essential for life. Such a low price results in water being used inefficiently. This paper proposes a system that supplements the existing price system with a cap-and-trade measure to reconcile conflicts among the goals of residential water use. It forces all people (independent of income) to be faced with reasonable price signals and to use water efficiently. The poor could, however, gain from trade and afford water. By taking advantage of the agent-based model, a simulation of this system applied to Taipei, Taiwan shows that those with lower income per capita are better off under this system even though the equilibrium price of residential water is higher. The simulated average price elasticity of market demand is ?0.449.     

Eco-Efficiency Assessment of Water Systems in China

With the transformation of water conservancy from traditional to eco-hydraulic aiming at sustainable development, the study on eco-efficiency of the water system has attracted a great deal of attention. This study aims to develop a methodology for evaluating the eco-efficiency of water systems of 31 administrative regions in China. Considering the multiple attributes of water systems and a piecewise linear technological frontier, the Rough Set Theory (RST) and Data Envelopment Analysis model (DEA) are combined to analyze the eco-efficiency of water systems. An input-and-output index system is established based on RST. The eco-efficiency for the water system of 31 administrative regions in China is calculated by DEA, and the characteristics of its spatial differences are discussed. The results show that there is a significant difference in the eco-efficiency of water systems: (1) On the whole, the efficiency value of north China is slightly higher than the south; (2) In the eight sub-regions of China, the north coastal area gains the highest efficiency score and the middle reaches of the Yangtze River obtains the lowest value; (3) There are 11 out of 31 regions at the best practice frontier. The spatial difference in eco-efficiency of the water system is a common phenomenon, which reflects the direct or indirect influence by economical, political, legislative, historical, cultural factors and other social development. Based on the above findings, some suggestions are made to improve the eco-efficiency of the water systems in China.     

The Assessment of Irrigation Efficiency in Buyuk Menderes Basin

While extending irrigated areas to augment agricultural production, irrigation efficiency should be increased not only to improve the agricultural production but also to obtain the sustainable use of valuable and limited water resources. Through the use of Data Envelopment Analysis (DEA), which is a linear programming technique to determine the relative efficiency of a decision-making unit, it is possible to decide whether the use of water in an irrigation district is efficient or not. In this study, an input oriented DEA model is constituted to focus on the efficient use of inputs, and the method is applied to the irrigation districts having similar types of agriculture in the Buyuk Menderes Basin, Turkey. This paper aims to determine the efficient irrigation district(s), in other words where the application of water is the most profitable, considering two inputs; water volume supplied and the total irrigated area, and one output, the total value of agricultural production. The weight restrictions consistent with decision makers’ value judgements are added as constraints into the DEA models to prevent excessive weight flexibility assigned to inputs and outputs. The results have provided the efficiency scores of the irrigation districts and numerically delineated desired features of the irrigation districts for maximum efficiency. The analyses for three study years have inferred the robustness of the results. It is concluded that DEA is a practical tool for detecting local inefficiencies and proposing possible improvements for irrigation districts that could offer the greatest potential for growth.     

Policy Options to Improve Water Allocation Efficiency: Analysis on Egypt and Morocco

Abstract

Because of political risk, economic feasibility, and cultural concerns, it has been a great challenge for economists to provide palatable remedies to governments to promote water allocation efficiency. Considering the limitation of water pricing to irrigation water, this research addresses questions of which strategic policy alternatives to water pricing might improve irrigation water allocation efficiency. An empirical framework is provided to compare irrigation policies for allocating scarce water to agricultural production in Egypt and Morocco. Partial-equilibrium agricultural sector models specific to Egypt and Morocco were employed for policy tests. Consumer and producer surplus from agricultural based commodities is maximized subject to various resources, technical, and policy constraints. Positive Mathematical Programming (PMP) was used to calibrate the model. Water pricing policy, water complementary input factor tax policy, and output tax policy are tested using these two agricultural sector models. Results suggest that effective policy depends on the social, economic, and environmental contexts of specific regions. For countries like Egypt where most agricultural land is irrigated, taxes on Nitrogen (N) fertilizer and energy and output tax on water-intensive and low profit crop production may be more effective than others. For the Moroccan case, taxation on crop inputs and outputs not only affect water use in the public irrigation sector, but also private irrigation sector and rain-fed as a whole. Water pricing and output tax policies are better suited and effective than water complementary input factor taxation. Findings from Morocco might be generalized to other countries with similar irrigation characteristics and diversity in irrigated (public and private) and rain-fed land. The results for both countries demonstrate that some of the strategic irrigation policies can work towards directing cropping decisions to less water intensive crops and also generating revenues for governments in situations where governments choose not to price water.     

基于SFA的工业用水节水潜力分析

构建基于随机前沿生产函数的工业用水节水潜力计算模型,认为节水潜力是技术充分有效、不存在任何效率损失情形下的工业最小用水量与实际用水量的差,是用水户在现有的生产技术、用水结构、水资源管理制度、用水意识、投资能力等因素综合作用下能达到的目标。以徐州市为例进行计算分析,指出徐州工业技术效率呈现上升趋势,总体节水潜力为当前用水量的22.52%。     

Rational Pricing of Water as an Instrument of Improving Water Use Efficiency in the Agricultural Sector: A Case Study in Gujarat,India

The agricultural sector in India accounts for over 85% of the total water used for various purposes in the country. However, the efficiency of water use in agriculture is very low, approximately 40% for surface irrigation and 60% for groundwater irrigation. Part of the reason for the low efficiency is the highly subsidized price of irrigation water that encourages the excessive application of water to crops. This paper is based on a case study conducted in the command area of a public irrigation canal in the state of Gujarat, India. It attempts to explore the role of the rational pricing of canal irrigation water in motivating farmers to use water judiciously and thereby enhance the water use efficiency in irrigated agriculture. The paper contends that farmers are sensitive to an increase in irrigation water charges, but unless the administered price is increased to the level that would prevail in a free market, it will not have its intended effect on irrigators.     

Impacts of Combined Technical and Economic Measures on Water Saving in Agriculture under Water Availability Uncertainty

In Emilia Romagna region (northern Italy), the Water Protection Plan (WPP) — a tool designed to reach the objectives of the Water Framework Directive — established different measures to achieve a good quantitative status of water bodies. The objective of this study is to evaluate the combined economic, agronomic and environmental impacts of four measures of the WPP on the “Renana” reclamation and irrigation scheme, and to quantify the water conservation in agriculture under the uncertainty of water availability. To this purpose, a mathematical stochastic model able to represent uncertainty in water availability was designed and implemented. Some data were collected from farms, and local sources were used as well to test the model. Each analyzed measure was simulated in a single scenario, and subsequently combined with other measures. The performed simulations are the following: application of volumetric water pricing (Scenario WFD1), awarding incentives for farmers to improve on-farm irrigation efficiency (Scenario WFD2a), combination of WFD1 and WFD2a (Scenario WFD2b), reduction of water abstraction in case of water shortage (Scenario WFD3a), combination of WFD1 and WFD3a (Scenario WFD3b), increasing distribution efficiency in the channel system (Scenario WFD4a) and combination of WFD1 and WFD4a (Scenario WFD4b). Results have shown that scenarios WFD2a and WFD4a generate a higher income for farmers and produce a positive ecological impact (water use and soil cover) but tend to increase total water use. Scenarios WFD1 and WFD3a have the opposite effects since they reduce farmers’ income but decrease water use as well. Only WFD1 could be favorable for the Board governing the scheme (RIB) in terms of economic returns. Finally, results have shown that combined scenarios WFD2b and WFD4b, respectively, could modify the trade-off between economic and environmental objectives and could be more effective since they significantly reduce water consumption and minimize losses in farmers’ income.     

Water Use Efficiency and Productivity of the Irrigation Districts in Southern Alberta

The data envelopment analysis (DEA) model was used to estimate the technical efficiency (TE) scores, the Malmquist total factor productivity (TFP) indices, and their implicit input shadow shares for 12 irrigation districts in Southern Alberta using data for the period 2008–12. The main purpose was to establish benchmarks so that future increases in conservation, efficiency and total factor productivity of water use (major goals of Alberta’s Water for Life strategy) can be assessed. Results of an input-oriented DEA model indicated that the irrigation districts were, on average, 84.3 % technically efficient in their input use, primarily the net water diverted. The output-oriented model indicated that the irrigation districts, alternatively, could expand their total irrigated areas by 58.3 % with the current level of input use. Over the period 2008–12, the year-to-year mean Malmquist TFP for the irrigation districts of Southern Alberta was estimated to be 0.98 %. Net water diverted was identified as the most important contributing input (76 %) to the TFP change. The second and third contributing factors were pivot irrigation technology (6 %) and precipitation (5 %).     

Groundwater Demand Management in the Great Lakes Basin—Directions for New Policies

Demand-side management should be used to maximize the efficiency of groundwater use. Implementation of conservation measures would decrease the volume of water use and also exert less pressure on the water distribution system as well as the wastewater treatment system. Allocation of ground water in the Great Lakes basin must conform to priorities established at the community level. Groundwater pricing should reflect the full costs arising from ground water use. A differential pricing structure would help conserve water in the residential and industrial sectors. A user-friendly database on ground water use, quality and quantity for the entire Great Lakes basin is also essential. New policies for sustainable groundwater allocation, regulating water prices for water conservation, conservation education, pollution prevention, recycling and reuse of water as well as effective information management provide new directions for managing the groundwater demand in the Great Lakes basin.     

Incorporating Water Demand Management into a Cooperative Water Allocation Framework

The impact of a water demand management plan on a water system and its users is investigated within a comprehensive cooperative water allocation framework. In particular, a demand management plan is incorporated into a two-step multi-period fair water allocation model. A modified cooperative game is designed for the sharing of additional net benefits under the scenario having water demand management. The results indicate that cooperation among water users can yield more net benefits, and a water demand management plan is able to lead to a further increase of the aggregated net benefits by means of water transfers from less productive users to more productive ones. By utilizing the modified cooperative game, fair sharing of additional net benefits ensures that every water user can expect to receive more net benefits and thereby water users are motivated by incentives to implement a water demand management plan which in turn improves water use efficiency. The results demonstrate that the demand management plan can be of great assistance in some arid and semi-arid regions.     

Estimating the Potential Impacts of Irrigation Water Pricing Using Multicriteria Decision Making Modelling. An Application to Northern Greece

A great challenge of the current European water policy is the implementation of volumetric water pricing in the agricultural sector, especially of Mediterranean countries, where irrigation is a necessary precondition of agricultural production and farmers’ income, but also the major consumer of water. The overall aim of the present work is to develop a methodology that will be suitable for the estimation of the potential environmental, economic and social impacts of irrigation water pricing. For this purpose, Multi-Attribute Utility Theory is implemented in order to simulate agricultural decision making at various water pricing scenarios. Water demand functions are then elicited, by means of the best crop and water allocation (farmers’ decisions) in each scenario. The European Water Framework Directive recommends that any issue concerning water resources management (including water pricing policies) should be developed at the river basin level. In this framework, a cluster analysis is performed to partition the river basin area (namely, Loudias River Basin, located in Northern Greece) into a small number of homogeneous sub-regions. The differential impact of water pricing in each region is then analyzed, and finally, an average water demand function is formulated for the whole river basin.     

Stochastic Goal Programming Model for Optimal Blending of Desalinated Water with Groundwater

A stochastic goal programming (GP) model is developed in orderto determine the daily production of desalination plants to meet the requirements of water blending stations (WBS) for major cities in the Eastern Province of the Kingdom of SaudiArabia. The WBS is assumed to be a control point in the systemwhere water is blended to satisfy the desired water quality, downstream of the control point. The desalinated water is blended with brackish groundwater extracted from several groundwater wells. The objective of the model is to minimize the goal deviations from the following priority levels: demand for blended water, control of salinity levels, depletion of groundwater and maximize the use of brackish water, demand forbrackish water at WBS, and production of desalinated water. Anessential element of the model is the input data; unfortunately,available data are not accurate due to the inherent uncertaintyassociated with it. This uncertainty will generate uncertainty in the model output, which affects reliability and confidence associated with the decisions. Thus, reliable planning should consider uncertainties associated with model input parameters.The developed stochastic model shows how Goal Programming (GP)modeling can be used to plan the water resources in the EasternProvince of Saudi Arabia, assuming that both supply and demandare uncertain.     

Urban Household Water Demand in Beijing by 2020: An Agent-Based Model

Beijing is faced with severe water scarcity due to rapid socio-economic development and population expansion, and a guideline for water regulation has been released to control the volume of national water use. To cope with water shortage and meet regulation goal, it has great significance to study the variations of water demand. In this paper, an agent-based model named HWDP is developed for the prediction of urban household water demand in Beijing. The model involves stochastic behaviors and feedbacks caused by two agent roles which are government agent and household agent. The government agent adopts economic and propagandist means to make household agent optimize its water consumption. Additionally, the consumption is also affected by the basic water demand deduced from extended linear expenditure system. The results indicate that the total water demand of urban households in Beijing will increase to 317.5 million cubic meters by 2020, while the water price keeps growing at a low level. However, it would drop to 294.9 million cubic meters with high growth of water price and low increment in per capita disposable income. Finally, some policy recommendations on water regulation are made.     

Efficiency Assessment of Water and Sewerage Companies: a Disaggregated Approach Accounting for Service Quality

This paper evaluates the efficiency of water and sewerage companies (WaSCs) by applying the weighted Russell directional distance model. This is a non-radial data envelopment analysis (DEA) model that allowed us to obtain an individual efficiency score for each input and output considered in the assessment. This study provides a pioneering approach to evaluating the efficiency of WaSCs, since previous studies on this topic were based on radial DEA models that only provide a global efficiency score. Moreover, three variables representing the lack of service quality were introduced into the model as undesirable outputs. An empirical application was carried out for the 25 largest Chilean WaSCs for 2013. The results illustrated that around one-third of the WaSCs in Chile are totally efficient. The inefficiency scores for each variable evidenced that one of the main challenges of the water industry in Chile is to reduce the percentage of unbilled water and that this issue is especially marked for medium WaSCs. As part of the second-stage analysis, some differences in performance between private and concessionary WaSCs were found, although the results were inconclusive. Several policy implications to help water companies’ managers and water regulators make informed decisions were drawn from our empirical analysis.     

北京市水资源利用相对效率的时空差异分析

以北京市为例,采用改进的数据包络分析方法（DEA）计算了2001-2009年北京市18区(县)的水资源利用的相对效率,利用探索性空间数据分析方法（ESDA）和局部空间自相关性分析方法,研究了北京市18区（县）的水资源利用相对效率的空间分布格局。结果表明：北京市各区、县水资源利用相对效率有所提高;空间分布呈随机性;没有显著的空间分布特征,即趋同或异质现象。与北京市经济发展的空间分布格局对比得出,北京市各区（县）的用水效率与其经济发展水平存在着一定的相关性。     

Optimization and coordination of South-to-North Water Diversion supply chain with strategic customer behavior

The South-to-North Water Diversion (SNWD) Project is a significant engineering project meant to solve water shortage problems in North China. Faced with market operations management of the water diversion system, this study defined the supply chain system for the SNWD Project, considering the actual project conditions, built a decentralized decision model and a centralized decision model with strategic customer behavior (SCB) using a floating pricing mechanism (FPM), and constructed a coordination mechanism via a revenue-sharing contract. The results suggest the following: (1) owing to water shortage supplements and the excess water sale policy provided by the FPM, the optimal ordering quantity of water resources is less than that without the FPM, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without the FPM; (2) wholesale pricing and supplementary wholesale pricing with SCB are higher than those without SCB, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without SCB; and (3) considering SCB and introducing the FPM help increase the optimal profits of the whole supply chain, supplier, and external distributor, and improve the efficiency of water resources usage.     

城市供水定价模式的比较分析及其启示

中国城市供水定价的目标是保证正常需求,抑制过量需求。对目前国际上比较流行的两种城市供水定价模式进行比较分析,指出分类分级定价模式符合中国实际,价格上限定价模式具有成本约束的优点,并提出中国城市供水定价改革的相关建议。     

基于水资源绿色核算的北京市水价

依据绿色国民经济核算原理，对经济社会用水造成的水资源质量和数量的变化进行环境经济综合核算，分析经济社会用水引起的国民经济全成本。以生产函数、投入产出模型与最优化方法为核心的宏观经济模型为基础，以现有社会劳动力、资本及经济社会用水总量为约束条件，以生态国内生产总值(EDP)最大为目标函数，建立北京市2000年水资源绿色核算的投入占用产出水价模型，对北京市2000年的经济社会用水理论水价进行深入探讨。研究结果表明，2000年北京市理论水价远大于实际计收的水价，实际水价未完全发挥出水资源供求信息的作用，水价的市场调节作用不明显。