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1.
Irrigation water pricing: differential impacts on irrigated farms   总被引:10,自引:0,他引:10  
European water policy, as set out in the Water Framework Directive (WFD), requires all EU Member States to implement volumetric water pricing at rates that roughly cover the total costs of providing water services. The objective of this paper is to develop a methodology that, for the different types of farm in an irrigable area, will enable us to analyse the differential impact that a pricing policy for irrigation water would have. For this purpose, Multi-Attribute Utility Theory (MAUT) mathematical programming models were used. The methodology is implemented on a representative area in the Duero Valley in Spain. Our results show the usefulness of differential analysis in evaluating the impact of a water pricing policy. This allows significant differences in the evolution of agricultural incomes to be observed, as well as the recovery of costs by the State, demand for agricultural employment and the consumption of agrochemicals resulting from rising prices of irrigation water in various groups of farmers within a given irrigated area.  相似文献   

2.
Evaluation of drought management in irrigated areas   总被引:4,自引:0,他引:4  
This paper focuses on the economic consequences of droughts for the irrigation sector. We develop a dynamic‐recursive mathematical programming farm model that assumes imperfect mobility of capital and labour as well as rational expectations about future water availability. The model is calibrated to 12 representative farms belonging to three irrigation communities of the Guadalquivir Basin (south Spain) and used to simulate the 1991–1997 period, which included 3 years of intense drought. Results indicate that the drought imposed significant costs on farmers, but show also that water managers partly exacerbated these costs by allocating excessive amounts of water to irrigators in the abundant years. The model is also used to evaluate the benefits of a perfect water supply forecast and to simulate the economic gains of a voluntary water banking scheme. Results show that the benefits resulting from the perfect forecast of water supply 1 year ahead would represent a relative gain of 5%. However, a voluntary banking system would allow farmers to increase their benefits by 32–82% depending on the supply system.  相似文献   

3.
Irrigation water productivity in Cambodian rice systems   总被引:1,自引:0,他引:1  
Knowledge of the marginal productivity of water is crucial for decisions about its allocation between uses, which is particularly important in the context of increasing competition for water. Using primary, plot‐level panel data, this article estimates the marginal productivity of water from supplementary irrigation in lowland rice systems in Cambodia, taking into account farmer and plot heterogeneity as well as self‐selection of supplementary irrigation. Our estimates indicate a range of elasticities for rice output with respect to water inputs of between 0.057 and 0.069 for wet season production, substantially lower than previous estimates based on either aggregate or trial data. We discuss the policy implications of these results, in particular with respect to the utility of demand management policies and the challenges they pose to the decentralization of water management to Farmer Water Users Groups.  相似文献   

4.
The overall goal of our article is to better understand which matters for water savings, farmer income and poverty in China's irrigation systems: incentives to managers or participation of farmers. To pursue this goal, the article has three objectives. First, we track the evolution of water management reform, examining the practice of providing incentives to managers, and increasing the participation of farmers. Second, we identify the impact of water management reform on crop water use. Specifically, we want to measure whether or not incentives to managers and farmer participation in water management institutions affect the performance of the irrigation system. Because we also are interested in the potential results of water management reform, the article explores how changes in incentives and farmer participation affect farmer income and poverty. Based on a random sample of 51 villages and 189 farmers in four large irrigation districts in Ningxia and Henan provinces, both in China's Yellow River Basin, our results show that the two major forms of water management reform, water users' associations (WUAs) and contracting, have begun to systematically replace traditional forms of collective management. Our analysis demonstrates, however, that it is not the nominal implementation of the reform that matters, but rather it is the creation of new management institutions that offer water managers monetary incentives that lead to water savings. In contrast to the original design of China's reform policies, participation of farmers has not played a role in saving water. Importantly, given China's concerns about national food production and poverty alleviation, the reductions in water, at least in our sample sites, do not lead to reductions in income and do not increase the incidence of poverty.  相似文献   

5.
Groundwater resources (GW) account for nearly 30% of the world's sustainable water supplies. Yet, this resource, which is fraught with externalities, has largely been left unregulated. The economic literature on GW is predominantly of a partial equilibrium type. We analyze GW regulation in a general equilibrium setting, focusing on the stabilization value of GW under natural (drought) and economic (rural–urban water transfer) shocks. A general equilibrium approach allows evaluating direct and indirect effects of GW regulation on agriculture and nonagriculture sectors and extends the scope for water policy. The analysis is applied to Morocco by extending an existing computable general equilibrium (CGE) model to include ground and surface water (SW) resources. We study effects of (i) an increase in GW extraction cost (e.g., as a result of prolonged extraction beyond natural recharge that lowers the aquifer's water table), (ii) a transfer of SW from rural (irrigation) to urban (domestic) use, and (iii) a reduction of water availability due to severe drought. We estimate the value of GW and assess the direct (partial equilibrium) and indirect (general equilibrium) impacts. We find that GW plays a critical role in mitigating the negative effects of these types of shocks.  相似文献   

6.
Groundwater depletion is a serious problem in Mexico. Several policy alternatives are currently being considered in order to improve the efficiency of irrigation water use so that extraction of groundwater is diminished. An understanding and quantification of different sources of inefficiency in groundwater extraction is critical for policy design. Survey data from a geographically extensive sample of irrigators is used to gauge the importance of common pool problems on input‐specific irrigation inefficiency. Results show that mechanisms of electricity cost sharing implemented in many wells have a sizable impact on inefficiency of irrigation application. Moreover, irrigation is very inelastic to its own unitary cost. Therefore, results suggest that policies aimed at eliminating electricity cost‐sharing mechanisms would be significantly more effective than electricity price‐based policies in reducing irrigation application. Results also show that well sharing does not affect groundwater pumping significantly, suggesting either a limited effect of individual pumping on water level or absence of strategic pumping by farmers sharing the wells.  相似文献   

7.
This paper investigates the factors influencing the decline in collective management of local commons and the impact of this decline on agricultural production and household consumption. The analysis is based on a village and household data set collected in 1999 in Tamil Nadu, India, where tank irrigation systems are managed collectively for rice cultivation by informal water users' organizations. Our statistical analyses find that one major reason for the decline in collective tank irrigation management is the dissemination of private well irrigation systems. Once the decline has occurred, our analyses predict that the gap in rice yields between farmers who have access to private wells and those who must rely solely on tanks will widen, with only the latter group suffering lower yields. Our analyses also find that the same pattern holds for levels of income and consumption because the affected farmers cannot sufficiently compensate for the loss of their rice income by diversifying their income sources to agricultural labor or nonagricultural work. In this way, the decline in collective management results in greater inequality and poverty.  相似文献   

8.
Irrigation water is essential for agriculture in the arid Drâa River basin in Morocco but climate change leads to increasingly unreliable water supply in the area. This article analyzes impacts of changing water inflow distributions on irrigation and farm income extending a conjunctive river basin model toward a stochastic modeling approach. Regional climate scenarios are used to derive a maximum likelihood density estimate of current and future water supplies. Based on these distributions, Monte Carlo simulations are performed to obtain stochastic model results on surface and groundwater irrigation as well as economic indicators for six oases along the river. The probability of farmers to receive revenues below the subsistence level is around 2% under current conditions, but this is likely to rise to rates of 6% to 15% depending on the underlying climate change scenario. The composition of water sources for irrigation will shift to more groundwater use. The river basin model is able to represent complex spatial interactions between oases as well as a partial complementarity between groundwater and surface water irrigation due to salinity management effects. Interestingly, the value of groundwater is not necessarily increasing under future climatic conditions as salinity problems are aggravated with expanded groundwater use.  相似文献   

9.
Irrigation with saline water has a positive impact on some quality indices of processing tomatoes, but with concomitant reductions in output quantity. This article studies the impact of the trade‐off between these two factors on optimal water management under waterlogging and costly drainage‐disposal conditions. The focus is on the content of total soluble solids as a quality measure affecting prices paid by California processors to tomato growers. A function relating quality to water and salinity applications and a quality hedonic‐price function are estimated and introduced into a static, field‐level mathematical programming model. The model calculates optimal water management under environmental regulations associated with drainage disposal in California. Findings indicate that only when the quality effect is taken into account does blending fresh surface‐water with saline drain‐water become an optimal strategy. Management and policy implications on the regional scale are discussed.  相似文献   

10.
This research investigates optimal price risk management strategies for fed cattle producers engaged in grid pricing. Stochastic simulation is used to determine optimal hedge ratios for fed cattle priced on a live weight basis or on a series of grids that vary in terms of premium/discount structure as well as base price. Results indicate that the optimal hedging strategy is greatly affected by the base price used in a particular grid. This has significant implications for pricing efficiency in the cattle market. Base prices that are linked more closely with downstream markets offer the potential to improve pricing efficiency; however, the risk associated with these prices is difficult to manage effectively with existing futures instruments.  相似文献   

11.
The dynamics of biomass growth implies that the yield of irrigated crops depends, in addition to the total amount of water applied, on irrigation scheduling during the growing period. Advanced irrigation technologies relax constraints on irrigation rates and timing, allowing us to better adjust irrigation scheduling to the varying needs of the plants along the growing period. Irrigation production functions, then, should include capital (or expenditures on irrigation equipment) in addition to aggregate water. We derive such functions and study their water-capital substitution properties. Implications for water demand and adoption of irrigation technologies are investigated. A numerical example illustrates these properties.  相似文献   

12.
The reform of water pricing policies may represent an effective instrument for enhancing the efficient use of water resource. However, policy makers fear that a change in the pricing methods may cause income loss for some farmers, and that this income inequality may generate public discontent and policy inertia. The aim of this paper was to compare some pricing methods in order to measure their effects on income distribution. The analysis focuses on the income distribution among different types of farms, and the income distribution between different social groups (landowners, capitalists and workers) in the short term. A linear programing model based on expected utility theory is used to take into account the effect of commodity prices and rainfall variability, which are among the most relevant factors affecting farmers’ income. According to the findings, water pricing schemes do not affect the income distribution among farm types, although a significant impact emerges on the distribution among social groups, and in particular on the wages of temporary workers.  相似文献   

13.
Water shortage has been a significant issue for several decades in the Texas High Plains. Agriculture has been identified as the main activity contributing to this shortage. To address this issue, many efforts have been focused on the possible adoption of sophisticated irrigation systems with high levels of water application efficiency. In this study, the entry and exit thresholds for the low‐energy precision application (LEPA) system are analyzed simultaneously in cotton farming in the Texas High Plains using a real options approach. The results show that the LEPA system is profitable only when cotton price is set above $1.59/kg. The exit (entry) threshold is consistently low (high) over a range of values for parameter changes including investment cost, exit cost, variable cost, risk‐adjusted discount rate, and volatility rate, so it is unlikely that farmers with irrigation systems in place would leave them easily. This implies that to attain the goal of saving water, Lubbock County needs to focus on convincing current farmers to replace old irrigation systems with new ones.  相似文献   

14.
This paper presents a bio‐economic model of Andit Tid, a severely degraded crop‐livestock farming system with high population density and good market access in the highlands of Ethiopia. Land degradation, population growth, stagnant technology, and drought threaten food security in the area. Drought or weather risk appears to have increased in recent years. The bio‐economic model is used to analyse the combined effects of land degradation, population growth, market imperfections and increased risk of drought on household production, welfare and food security. We find that the indirect effects of drought on household welfare through the impact on crop and livestock prices are larger than the direct production effects of drought. Provision and adoption of credit for fertiliser, although risky in itself, may lead to increased grain production and improved household welfare and food security. Provision of credit may have a negative effect on conservation incentives but this effect may be mitigated by linking a conservation requirement to the provision of credit for fertiliser.  相似文献   

15.
Increasing water scarcity combined with an increasing demand for food and water for irrigation call for a careful revision of water use in agriculture. Currently, less than 60% of all the water used for irrigation is effectively used by crops. Based on the new version of the GTAP‐W model we analyze the effect of potential water savings and the welfare implications of improvements in irrigation efficiency worldwide. The results show that a water policy directed to improve irrigation efficiency led to global and regional water savings, but it is not beneficial for all regions. The final effect on regional welfare will depend on the interaction of several different causes. For instance, higher irrigation efficiency changes opportunity costs and reverses comparative advantages, modifying regional trade patterns and welfare. For water‐stressed regions the effects on welfare are mostly positive. For nonwater scarce regions the results are more mixed and mostly negative. The results show that exports of virtual water are not exclusive of water abundant regions.  相似文献   

16.
We examine factors affecting the success and failure of collective action toward the management of local commons. Using cross‐section survey data on the activities of irrigators' associations in the Philippines, regression analysis is conducted to identify factors underlying the success and failure in farmers' organizing collective action for the maintenance and operation of irrigation systems. We find that collective action is difficult to organize where (a) water supply is uniformly abundant; (b) water supply is greatly different between upper and lower streams in lateral; (c) the size of the association is large; (d) population density is low; (e) the share of nonfarm households is high; and (f) the history of irrigated farming is short. Our findings suggest that these difficulties can be overcome with adequate supports of state agencies to promote community‐level cooperation.  相似文献   

17.
Irrigators’ policy preferences for water reallocation programs usually take the form of proportional data, where one option will be relatively more or less favored than another in the composition of a government's total budget apportionment to address water reform. This study applies a zero‐one inflated beta regression to model Murray–Darling Basin irrigators’ preferences for market‐based water policy programs. Market‐based arrangements are more likely to provide efficient solutions to water reallocation problems, particularly where future uncertainty and appropriate pricing induce irrigator preferences for such programs. Our modeling of drivers of irrigator preferences for government expenditure on market‐based programs identified different determinants of zero (a corner solution) and proportional outcomes for the reallocation of Murray–Darling Basin water. In addition, the proportional modeling identifies some variables (namely, state regional influences, the type of farm production and recent debt, low income, or water allocation stressors) that increase engagement with market‐based programs. Interestingly, while price variables are important and statistically significant, they appear to be less relevant to program engagement than other influences.  相似文献   

18.
Drought and future water scarcity in the Murray–Darling Basin (MDB) will continue to restructure the irrigation industry in the coming decades. There has been little work conducted in Australia that has modelled farm exit or exit intention. ABARES farm survey data were used to model irrigators’ farm exit intentions across the southern MDB from 2006 to 2013. In particular, we examined the hypotheses that drought and water scarcity positively impacted on farm exit intentions and that it is the poorest performing farms that intend to exit in times of drought. Results revealed that water scarcity impacts varied considerably. There was only weak evidence to suggest that irrigators’ exit intentions were higher in times of drought, but there was stronger evidence to support the influence of a lagged water scarcity impact on farm exit intentions during periods of nondrought (e.g. intending to exit at times when the property market was less depressed). There was also strong evidence that poorer performing farms (measured by rates of return and higher debt over a certain level) were more likely to have exit intentions in drought periods, but not necessarily so in nondrought periods. Older age is the most consistent predictor of farm exit intentions across all industries, though it was most significant in drought periods.  相似文献   

19.
Spot water markets and risk in water supply   总被引:1,自引:0,他引:1  
Water availability patterns in semiarid regions are typically extremely variable. Even in basins with a highly developed infrastructure, users are subject to unreliable water supplies, incurring substantial economic losses during periods of scarcity. More flexible instruments, such as voluntary exchanges of water among users, can help users to reduce risk exposure. This article looks at the effects of spot water markets on the economic risk caused by water availability variations. Our theoretical and empirical risk analyses are based on the random profits of water users. Profit probability density functions are formally and graphically characterized for both water sellers and buyers under several possible market outcomes. We conclude from this analysis that, where water supply is stochastic, water markets unambiguously reduce both parties' risk exposure. The empirical study is conducted on an irrigation district in the Guadalquivir Valley (Southern Spain), where there is a high probability of periods of extreme water scarcity. Water demand functions for the district representative irrigators and a spatial equilibrium model are used to simulate market exchanges and equilibrium. This programming model is combined with statistical simulation techniques. We show that the profit probability distribution of a representative irrigator is modified if water exchanges are authorized, leading to risk reductions. Results also indicate that if the market were extended to several districts and users that are subject to varying hydrological risk exposure, extremely low‐profit events would be less likely to occur. In sum, we show that exchanging water in annual spot markets can reduce farmers' economic vulnerability caused by water supply variability across irrigation seasons. These results support the water policy reform carried out in Spain in 1999 to allow for voluntary water exchanges among right holders.  相似文献   

20.
Many water management problems have arisen in past Asian irrigation projects. They have been characterized as a vicious cycle involving the lack of maintenance, poor irrigation service, low rates of fee collection, inadequate institutional arrangements, and lack of user participation. This article argues that we have generally agreed on a strategy to address these problems and asks whether or not the strategy is being implemented effectively. A review of the irrigation record of six countries in Asia (including India and China) shows that they have implemented several of the key irrigation management reforms but that high transaction costs have delayed reform.  相似文献   

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