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Nitrogen (N) is a key input to food production. Nearly half of N fertilizer input is not used by crops and is lost into the environment via emission of gases or by polluting water bodies. It is essential to achieve production levels, which enable global food security, without compromising environmental security. The N pollution level expected by 2050 is projected to be 150% higher than in 2010, with the agricultural sector accounting for 60% of this increase. In this paper, we review the status of the pollution from N fertilizers worldwide and make recommendations to address the situation. The analysis reviews the relationship between N fertilizer use, N use efficiency, no-point pollution, the role of farmer management practices, and policy approaches to address diffuse pollution caused by N fertilization. Several studies show a lack of information as one of the main hurdles to achieve changes in habits. The objective of this study is to highlight the gravity of the current global non-point pollution as well as the need for a communication effort to make farmers aware of the relationship between their activity and N pollution and, therefore, the importance of their fertilizer management practices.

Different segments of society have shown interest in understanding the effects of human activities on ecosystems. To this end, the aim of this article is to analyze the scientific literature on the application of the Drivers-Pressures-State-Impact-Response (DPSIR) conceptual model to identify the parameters used to describe the causal interactions that occur between agriculture and aquatic ecosystems at the watershed scale. In this way, descriptive indicators were established for the data of 63 publications collected through Scopus, Web of Science, and Science Direct. The results confirm the great heterogeneity in the interpretation of the pressure, state, and impacts components. Part of this discrepancy can be attributed to the use of different indicators, as the model is flexible and generic. Overall, the DPSIR is a tool used not only in the scientific field, but also has demonstrated its potential to guide public policy formulation, planning, and decision-making in water resource management.

This study describes the evolution of the Spanish irrigated sector and focuses on water abstraction, water consumption, and energy use in the period 1950–2017. The analysis shows evidence of the basins reaching closure state and the impact on energy use from irrigation supply. The response in the context of an increasing water demand with a limited supply has been investment in water-saving and conservation technologies (WSCT) with the transformation of furrow-irrigated areas into those of drip and sprinkler, resulting in an increase in irrigation efficiency. The effect of this policy implies an increase in energy use by a factor of six in the period while the irrigated area triples and its water use doubles in the same period. Water abstraction reaches its peak in the year 2004 and decreases slightly as a consequence of subsidies to WSCT. The impact on energy consumption in pumping and treatment illustrates the water-energy nexus in Spain’s agriculture and the change in the water policy paradigm from supply augmentation towards demand management.

This article evaluates economic use values of groundwater and examines the trade-offs between agricultural and recreational uses of the Fuencaliente Aquifer in southern Spain. This case stu...

This chapter provides a methodology to analyse the allocation of reused water. The tool has been developed for the Guadalquivir River Basin Authority, allowing decision makers to rank the actions on the reutilization of urban water for agriculture. The decision support is based on four groups of attributes: (1) resource supply, (2) environmental impact, (3) technical and economic feasibility and (4) social and institutional impact. A multicriteria decision method is proposed to aggregate all selected indicators. The results allow the River Basin Authority to classify different water requests of reused water, according not only to their technical knowledge, but also to the experience of different experts and stakeholders in water management.

This paper proposes a methodology to compute a cost recovery ratio directly from the System of Environmental-Economic Accounting for Water (SEEA-Water) standard tables. The methodology is applied to the Guadalquivir River Basin in southern Spain. Results illustrate that it allows cost recovery analysis in line with Water Framework Directive Article 9. Wider adoption of the methodology would enhance comparability and knowledge sharing between regions, countries and sectors both in the European Union and worldwide.

While many studies have employed stated preferences methods to estimate the value of non-market ecosystem goods and services, contingent valuation (CV) still generates a significant amount of criticism. Besides ethical concerns, two of the key criticisms relate to insensitivity to scope and order effects. We examine the expectation that the presence of order effects in stepwise disclosure procedures affects the degree of scope sensitivity. We use data from a CV exercise asking farmers in Southern Spain to value two different levels of guarantee of water supply for irrigation in a context of water scarcity. We find that despite order effects being present, they do not affect the existence or the degree of sensitivity to scope. We conclude that, in the light of the mixed evidence found in the literature and the results of our study, it does not seem justified to ascribe order effects and their connection with sensitivity to scope to study design alone (e.g. step-wise versus advanced disclosure, top-down versus bottom-up). The nature of the environmental good under valuation also matters. Our study of irrigation water as a common-pool resource suggests that, when clear private benefits also exist, these appear to override any 'good cause dumping effect' that might arise from the public good component.

Biodiesel is a biofuel obtained from vegetable oils or animal fats by transesterification with methanol, so that it offers a very promising alternative respect to diesel fuel, since it is able to provide a suitable substitute for the fossil diesel in unmodified internal combustion engines, pure or in blends. However, a major barrier exists to consolidate this conventional biodiesel, as the more suitable biofuel for the replacement of fossil fuel. This drawback is related to the significant amount of glycerol obtained as a byproduct in the transesterification process, which exceeds at least 10% by weight of oil used as raw material. Thus, future widespread use of biofuels depends on developing new process technologies to produce high quality transportation fuels from biologically derived feedstocks, which avoid this key handicap. These new biofuels, like the biodiesel, need to be also compatible with the fossil fuel as well as with existing transportation infrastructures to be economically feasible. In this respect, various alternative methods are currently under development to convert vegetable oils into a high quality diesel fuel, fully compatible with petroleum derived diesel fuel but avoiding the existing glycerol glut. The present review aims to explore the current state of available technologies and recent information in research, production practices and engineering developed to produce alternative high-quality diesel fuel from vegetable oils, by hydrotreating of triglycerides in conventional oil refineries (green diesel) as well as those novel biofuels that integrate glycerol into their composition ( Gliperol®, DMC-Biod® and Ecodiesel®) and the respective technologies for their productions. These very recent biofuels obtained from oils and fats, seek to achieve greater atom efficiency (ideally 100%) because nor glycerol neither other byproduct is generated, avoiding any purification treatment, so that the overall production process of the biofuel is in large extension simplified.

Deficit irrigation (DI) is an agricultural practice in which the volume of irrigation water applied during the crop cycle is below the irrigation requirements for maximum production, the aim of which is to increase irrigation water productivity. Most research on this technique has focused on agronomic strategies while the economic and environmental consequences have received little attention. This study aims to shed some light on this matter and presents preliminary results regarding the implications of DI with respect to the sustainable use of water resources. The analysis is based on the DPSIR analytical framework (Driving force/Pressure/State/Impact/Response) and the microeconomics of DI. The case study focuses on intensive olive groves in the Guadalquivir river basin in Southern Spain (where olive cultivation accounts for 50% of the total irrigated area). The analysis shows that the widespread use of DI practices, which is the farmers’ response to a decreasing net water supply and falling farm incomes (driving force) in the context of a mature water economy, may help to break the DPSIR chain of causality, provided that there are restrictions on any expansion in irrigated area. They can, thus, play a role in achieving sustainable water use. Conversely, demand and supply (regulator) responses involving raising the price of water would lead to higher pressures on the resource and represent a negative driving force in our DPSIR model.

This paper develops a methodology for the economic analysis of water use proposed by the Water Framework Directive (WFD) based on the System of Environmental-Economic Accounting for Water (SEEA-Water) standard tables. Our proposal satisfies the requirements for the economic characterization set out in Article 5 of the WFD. A case study in the Guadalquivir river basin shows a similar characterization in the baseline scenario to previous studies, including apparent water productivity. The main contribution of our research, however, is the proposal of a methodology that would enhance comparability and knowledge-sharing between regions, countries, and sectors both in the European Union and worldwide.

Economics plays a double role in the field of water management, firstly as a powerful analytical tool supporting water allocation and policy decisions, and secondly in the form of policy instruments (water pricing, markets, etc.). This Special Issue presents a platform for sharing results connecting excellent interdisciplinary research applied to different regional and sectoral problems around the world. The 22 peer-reviewed papers collected in this Special Issue have been grouped into five broad categories: Water valuation and accounting; Economic instruments; Cost effectiveness and cost-benefit analysis; andWater productivity and Governance. They are briefly presented

It is currently a much debated topic the potential economic benefits of biomass use for biodiesel production in arid lands. In this respect, the main focus has been directed to determine which different plant species are highly adapted and capable to produce significant amounts of triglycerides to be used in the biodiesel industry under arid conditions. However, very few studies have addressed the technological changes that will be needed to convert triglycerides into biofuels without making a large consumption of scarce water, as it is demanded by current technology. Beside, with current conventional transesterification technology, the production of glycerine as a byproduct is also a serious problem because of the large water requirements needed for its removal from biodiesel, before it can be used in motor engines. The main methods commonly employed to reduce the viscosity of vegetable oil in order to be used in diesel engines are its high dilution with petrodiesel (

This research examines stakeholders’ perceptions of and preferences for water markets in agriculture, focusing on the likely barriers that might refrain them from participating in such markets. The research was carried out on the Guadalquivir River Basin and involved semi-quantitative methods, combining a structured survey and focus group discussions. A very simple questionnaire was administered to each irrigation stakeholder (i.e., managers, water right holders and non-holders). The main result is that stakeholders will only keep selling water seasonally as the rights remain linked to the land. Nonetheless, some relevant differences among stakeholders were found. Managers seem to be more interested in selling water than farmers. Another important discrepancy was found between water rights holders and non-holders. Access to a water rights system, types of existing infrastructure, and legal and administrative aspects are also important factors influencing the acceptability of water trading in the study area. These results might be helpful to policymakers who are currently evaluating the potential for water markets in Europe and have little observable market data to work with.

The objective of this research is to gain knowledge in the process of basin closure of a Mediterranean European river. The paper analyses the evolution of water demand and interactions between users and water resources, focusing on irrigation as the main actor of change. The Guadalquivir River Basin has been managed through a centralized and hierarchical system for almost 80 years, which facilitated the evolution of a large and profitable agricultural sector that in turn has driven the basin towards closure, defined as those basins with a relatively small amount of uncommitted run-off. We distinguish the following elements in the evolution towards closure: (a) decreasing farm income; (b) increase in irrigated area and factor intensification as a response to this; (c) expansion of irrigation to formerly rainfed crops (i.e. olive groves); (d) new demand from other sectors; (e) increase in environmental flow control; (f) reduction in water allocation; (g) increase in water costs; (h) introduction of water sa...

This paper considers farmer's stated responses to CAP scenarios, identifies the extent to which these plans would be influenced by the introduction of CAP abolishment from 2014 and considers the implications in terms of likely changes (i.e. increases or decreases in the deployment of chemicals and water resources on the farm). The analysis uses data from a large sample survey of household farmers across 11 case studies in 9 EU countries. Intended responses of farmers to the CAP scenarios are analysed by means of logistic regressions. The results indicate that CAP abolishment would not stimulate strong agricultural changes in resource use, rather it appears to be reinforcing many existing trends, namely towards decreasing chemical use and steadying water use. However, CAP abolishment would impact unevenly on the farm community and different farming situations are associated with different types of reaction. In addition, significant regional differences have been found according to the model regression. Indeed, in the case of New Member States, farmers show a greater preference to decrease chemicals and water use if the current CAP support was abolished. On the basis of the results presented in this paper some policy implications emerge.

This paper analyzes the impact of droughts on agricultural water productivity in the period 2004–2012 in the Guadalquivir River Basin using the System of Environmental-Economic Accounting forWater (SEEA-Water). Relevant events in this period include two meteorological droughts (2005 and 2012), the implementation of the Drought Management Plan by the basin's water authority (2006, 2007 and 2008), and the effects of irrigated area modernization (water-saving investment). Results show that SEEA-Water can be used to study the productivity of water and the economic impact of the different droughts. Furthermore, the results reflect the fact that irrigated agriculture (which makes up 65% of the gross value added, or GVA, of the total primary sector) has considerably higher water productivity than rain-fed agriculture. Additionally, this paper separately examines blue water productivity and total water productivity within irrigated agriculture, finding an average productivity of 1.33 EUR/m3 and 0.48 EUR/m3, respectively.

This research paper analyzes the economics of deficit irrigation based on the use of subjective estimates of the crop yield–water relationship to determine water supply in irrigated olive groves. Interviewed farmers were asked to give three estimates for the yield-water relationship as a function of water supply (full irrigation, usual deficit irrigation and extreme deficit irrigation). Those responses are contrasted with the actual irrigation dose and the results appear to support the hypothesis that a majority of farmers use deficit irrigation as a strategy that maximizes the value of limited water input rather than the conventional microeconomic behavior of maximizing the return to land Secretaría General de Ciencia, Tecnología e Innovación MINECOAGL2014 - 533417 - R

The European Water Framework Directive (WFD) requires the good ecological status of surface water bodies, which implies the improvement of both their physicochemical condition, as well as their flow and continuity. The WFD prescribes the assessment of environmental and resource costs and benefits associated with implementing these improvements. The recent literature focuses almost exclusively on the assessment of the economic values related to quality aspects. However, in much of southern Europe, fulfilling the WFD goals will greatly depend on maintaining sufficient water flow, as well. This study aims to fill this gap by assessing the non-market value of allocating enough water to the environment to ensure environmental services are sustained when water is scarce. The non-market value of guaranteeing water supply for secondary household uses is also estimated. Using the Guadalquivir River Basin in Spain as a case study, a choice experiment is applied with scenarios characterized by varying water flow levels and accompanying environmental impacts, and a different frequency of household water restrictions. The results show that the population derives significant benefits not only from the direct use of water, but that also holds non-use values related to the ecological status, although the latter has a considerably lower impact on consumer surplus. Additionally, we conclude that the costs of implementing the water saving measures currently included in the Program of Measures seem to be proportionate to its benefits in this case.

The EU Water Framework Directive represents a major change in the management of water resources and sets ambitious ecological objectives for all European waters. In the Directive, the economic assessment of the non-market environmental benefits of water quality improvements plays a crucial role. Studies valuing these benefits are now appearing in the literature, applying stated preference valuation techniques. However, these techniques are often criticized for providing only narrow mono-criterion information to the decision-making process. The research presented here builds on a recent line of investigation that combines monetary stated preference tools, in this case a choice experiment, with multi-criteria analysis, in this case the Analytical Hierarchy Process (AHP). We argue that the AHP can contribute to a better understanding and interpretation of the choice experiment results by exploring the criteria involved in respondents' trade-off between the attributes. The AHP provides relevant insights for the application of use-based water quality ladders in the valuation of environmental benefits in the context of the WFD. Results also show the importance of the spatial dimension of preferences for water quality.

This paper reports results from the European project WADI which evaluates the sustainability of the European irrigation sector under different policy scenarios. Results presented are based on the generation of farm level water demand curves through multicriteria mathematical programming models. The results are compared across regions and matched against a review of water pricing policies that were in place in various European Union member states and accession countries prior to the entering into force of the Water Framework Directive (WFD). The results emphasise the variability of behaviour of irrigated systems and the need for a more clear understanding of policy objectives before implementing any policy instrument. Once the objectives are clarified, economic models can contribute to understanding the appropriateness of different management strategies and to the effectiveness of different policy instruments.

[EN] This research analyses the subjective crop yield-water relationship and proposes a method to determine water supply in irrigated olives. The probability density for water response functions (PDF) is elicited from a series of interviews carried out on a wide group of farmers. The elicitation technique is based upon the triangular distribution (highest possible, most frequent and lowest possible) and estimates of yield related to water supply (low, ‘normal’ and full irrigation). The model presented illustrates the possibility of implementing simple decision models to support farmers to manage water considering the objectives of maximizing profit and minimizing risk, [ES] La investigación analiza la función subjetiva de producción de agua (respuesta producción-riego). Se han obtenido funciones de densidad de probabilidad de respuesta al riego basadas en la función triangular (rendimiento ‘más probable’, ‘pesimista’ y ‘optimista’) correspondientes a diferentes dosis de riego (‘completo’, ‘medio’ y ‘bajo’). A partir de esta información se plantea un modelo de decisión de tipo normativo para determinar la dosis óptima de riego en olivar intensivo que incluye rentabilidad esperada y riesgo entendido como la probabilidad de no alcanzar un umbral prefijado de ingresos, This research has been financed by Secretaría General de Ciencia, Tecnología e Innovación (MINECO). We thank our colleagues L. Mateos and F. Orgaz who provided insight and expertise that greatly assisted the research, and we also thank to the anonymous reviewers whose comments improved the earlier version of the manuscript.

A multiperiod model based upon a multicriteria objective function has been developed for a representative area of the Guadalquivir Valley, dividing the irrigated area into homogeneous types of farming as identified by cluster analysis. The model was applied to different future scenarios with a time horizon of 10 years and several different farming environments. A set of eight sustainability indicators has been evaluated for the model. The results show that the evolution of crops over time is closely related to the political environment regarding the Common Agricultural Policy (CAP) and the application of the Water Framework Directive (WFD). Methodological innovation has included the successful simultaneous introduction of MCDM and multiperiod programming techniques applied to agriculture and scenario development.

Irrigated agriculture is directly influenced by various EU policies, especially the CAP andmore recently the Water Framework Directive (WFD). The demand for water by agricultureis largely determined by CAP policy. On the other hand, the objective of the WFD is toregulate the supply (cost, quality, quantity) of water to agriculture. This work examinesthe relationships between these two policy instruments and applies a scenario analysis to acase study in central Spain using a multi-criteria model of farmer behaviour. The resultsshow that the two instruments must be co-ordinated in order to meet socio-economic goals(farmers’ income and labour demand) and environmental protection (water-use efficiency).

The single objective—profit maximization—has been the classical and neoclassic model for farmer’s decision making. Nowadays, it is recognized that other and conflictual objectives are important concerns to the process, making the multi-criteria methodologies more suitable to the agricultural reality. This chapter aims to identify and find the objectives and priorities of the Azorean dairy farmer’s decision making. The proposed methodology is based on multi-criteria models, by simulation of the dairy farmers’ behavior through data of the Farm Accountancy Data Network. This allows to define a surrogate utility function for a dairy farm typology, regarding the different grazing systems. Five main objectives were previously considered: profit maximization, risk minimization, labor seasonality minimization, leisure maximization, and also deviations to the goal of total labor minimization. The results show that in any group of Azorean dairy farms, the decision making process seems to be influenced by three conflictual objectives: profit maximization, labor seasonality, and risk minimization. Also, the farms’ objectives depend on the intensity of grazing systems and by other socioeconomic factors. That is, farmers’ behavior is not always explained by profit (exception in the low intensity grazing systems), which is unusual under the traditional paradigm. Some explanations may be appointed for this situation and one is related to the dairy farms income that can be enough to maintain the farm and family income. If the economic objectives are satisfied, then the farmers can have other priorities.

Linear programming (LP) has been widely used to solve company resource allocation problems. The technique’s ability to predict how companies will adjust to changes in a variety of exogenous factors is well known, and when used at company level, it enables us to avoid aggregation problems. The decision-maker’s objective in this type of research is to maximize profit estimated as gross margin. We apply the LP model to three farms in three different irrigation units that, we believe, provide a representative sample of Spanish irrigated agriculture. In focusing on the goals of this research we stress that water pricing as a single instrument for control of water use is not a valid means of significantly reducing agricultural water consumption. This is because consumption does not fall until prices reach such a level that farm income and agricultural employment are negatively affected. If water pricing is selected as a policy tool, among the consequences for agricultural sector will be that: farm income will decrease by around 40% before water demand decreases significantly. The impact of this reduction on rural areas that are dependent on irrigated agriculture will be catastrophic. Secondly there will be a reduction in the number of crops available for farming, with the consequence of a smaller number of alternatives and greater technical and economic vulnerability of the agricultural sector. Finally when water consumption decreases as a consequence of substitution of crops with higher demands for water (cotton, sugar beet, onions, corn) there will be a significant loss of employment both directly on farms and indirectly on processing facilities. These conclusions are drawn from our analysis of three irrigation units in Spain, but we believe that they offer a realistic estimate of policy impacts on the irrigated sector of Spanish agriculture. Even if price increases are not a suitable policy because of the high negative impact, we suggest that a price (around 2 PTAs/m 3 ) might be of interest in order to make farmers aware of the scarcity of

Irrigated agriculture has been analysed in Spain in recent years because of its high water consumption and its apparent ineAciency. Several possibilities for water policy have been debated, in particular the pricing of irrigation water. This paper aims to contribute to this discussion by simulating the impact that a policy based upon the price of water could have on agricultural production, analysing the economic, social and environmental implications of such a water policy. This research introduces a methodology for deriving water-demand functions in contexts in which farmers’ behaviour is not explained by the maximisation of gross margin but by a utility function with several conflicting criteria. This methodology utilises a weighted-goal programming approach to estimate a surrogate utility function for the farmer’s decision process; this in turn is used to estimate the value of water demand in irrigated crop production using utility-derived demand functions. The empirical results of this study stress that water pricing as a single instrument for controlling water use is not a satisfactory tool for significantly reducing water consumption in agriculture. The reason for this is that consumption is not reduced significantly until prices reach such a level that farm income and agricultural employment are negatively aAected. The results also show that the estimated water-demand curve is diAerent when a multicriteria utility function rather than the classical profit maximisation hypothesis is employed. # 2000 Elsevier Science Ltd. All rights reserved.

This study aims to uncover the factors that influence farmers’ attitudes towards water allocation trading. In the study, we simulate two water availability scenarios, an average year and a drought year, in a contingent valuation experiment with 241 farmers. A survey was held in the spring of 2012 in the Guadalquivir and Almanzora River Basins. First, we estimated a multinomial logit model to determine the factors that influence farmers to decide to participate in our hypothetical market. We then analysed the structural and socio-economic factors determining the monetary value of traded water using Heckman’s two-step model. Our results indicate that those farmers who are more innovative and have had agricultural training show a higher willingness to participate in water trading. Additionally, low water-supply guarantee and appropriate information about seasonal water availability increase the probability of participation. Higher willingness to pay (WTP) for water is found in horticulture and among farmers who grow citrus and other permanent crops; lower water selling value (WTA) is found in farms with extensive annual crops and traditional olive groves. However, monetary values (WTP/WTA) are strongly dependent on the current cost of irrigation water services. While findings of this research seem to support the idea of diffusion innovation theory, the existence of ethical concerns that might influence farmers’ acceptance of irrigation water markets needs further analysis

This research measures the Azores dairy farms’ technical efficiency by applying a non-parametric efficiency analysis to a panel data of 122 dairy farms from the Azores, Portugal, for 1996. The analysis used DEA with constant and variable returns to scale models, with an input-oriented model approach. Two outputs (milk production and subsidies) and three inputs (agricultural area, number of dairy cows and variable and fixed cost) were considered relevant. The results suggest that the average technical efficiency is very low (66.4%) compared with published research data, and only a few (7%) dairy farms were found to be efficient.

The improvement in the water quality resulting from the implementation of the EU Water Framework Directive is expected to generate substantial non-market benefits. A wide spread estimation of these benefits across Europe will require the application of benefit transfer. We use a spatially explicit valuation design to account for the spatial heterogeneity of preferences to help generate lower transfer errors. A map-based choice experiment is applied in the Guadalquivir River Basin (Spain), accounting simultaneously for the spatial distribution of water quality improvements and beneficiaries. Our results show that accounting for the spatial heterogeneity of preferences generally produces lower transfer errors. © 2012 Elsevier Ltd.

The article proposes a multi-criteria approach for dealing with risk when modelling an agricultural system through the simultaneous use of risk and game-theoretic programming. The use of multi-criteria techniques enables the decision maker to study the trade-offs and conflicts between profitability (expected returns) and risk (measured either by Partial Absolute Deviation (PAD) or minimum gain). The research for this paper suggests that, in practice, solutions generated by risk and game-theoretic programming are quite similar. A by-product of this research has been to clarify the relationships between stochastic efficiency and target MOTAD, and game-theoretic efficient sets.

This paper presents an application of MOPGP to wildlife management. The case study is the development of a game management operational plan for deer in Southern Spain. As there are two species, ecologic and economic conflicts are in conflict. The solution procedures start with a Multiobjective analysis of the efficient set, and is complemented by using Lexicographical Goal Programming to obtain a “satisfactory” operational plan. This research proves that management models can be improved by using multicriteria approaches, especially when a satisfactory combination of methods is employed.

Irrigated agriculture has come under close scrutiny in Europe recently because of its high share of total water consumption and its apparent inefficiency. Several water policies have been advocated, in particular the use of economic instruments such as water markets. This paper simulates the impact of a policy based upon water markets on agricultural production in the internal river basins of Catalonia (Spain). This zone presents certain particularities that make it very interesting to study: competition between sectors for the resource (agriculture-urban consumption-recreational uses), recent periods of resource insufficiency and conflicts between irrigators as a result of the measures taken by the hydraulic administration in drought situations. The results show that these markets would guarantee an optimal reassignment of the resource in situations of supply restrictions, and although compared to the situation without markets they would not mean higher economic profits for the irrigators, they could prevent conflicts between them. Nevertheless, doubts exist about their acceptance by irrigators. Últimamente se ha puesto en duda el papel económico del regadío en Europa, debido al elevado consumo de agua que representa, así como a su aparente baja eficiencia de uso. Al mismo tiempo, las políticas tradicionales de gestión de aguas están en entredicho, surgiendo nuevos planteamientos, destacando entre ellos el uso de instrumentos económicos como los mercados de aguas. Este artículo analiza el impacto sobre la producción agrícola de la instauración de mercados de aguas en un área de riego comunitario ubicada en las cuencas internas de Cataluña (España). Esta zona presenta ciertas particularidades que hacen que su estudio sea especialmente interesante: se trata de un área con una elevada competencia intersectorial por el uso del recurso (agricultura-consumo urbano-usos recreativos), recientes periodos de insuficiencia en el suministro y conflictos entre regantes como resultado de las medidas tomadas por la administración hidráulica en caso de sequía. Los resultados obtenidos muestran que los mercados garantizan una reasignación óptima del recurso en situaciones de restricción del suministro, y aunque globalmente no generan una ganancia económica muy elevada respecto a la situación sin mercado, sí podrían evitar conflictos entre regantes. Sin embargo, existen dudas sobre su aceptación práctica por parte de dichos regantes.

The analysis of the decision-making process in agricultural enterprises is approached with the development of a methodology based upon two stages: firstly we enlarge our knowledge of the system under study by performing grouping operation - cluster analysis - of the farm enterprises. The result of this stage is to classify farms according to crop pattern, which is the basis for the second stage of analysis: the system is studied by solving a weighted goal programming to approach the weights given by different farmers to the objectives of the decision process. This methodology is applied to two nearby but different irrigation units in Southern Spain, and we found that there was an important degree of heterogeneity in production plans explained by differences in objective weights.