No full-text available
To read the full-text of this research,
you can request a copy directly from the author.
Combining flexible regulatory and economic instruments for agriculture water demand control under climate change in Beauce
Abstract
Agricultural water management is becoming a critical issue in many parts of the world and cost-effective water policies are required to control water use. We examine the case study of irrigated agriculture in Beauce, France (9750 km2, Europe's largest cereal producing region). We explore the mechanisms for water abstraction control involving a combination of regulatory and economic instruments. The analysis is conducted with a hydro-economic model that includes a calibrated economic model and a semi-distributed calibrated hydrogeological model. First, we analyse the system currently used to manage groundwater abstraction. It includes a flexible quota system, revised annually as a function of the state of the groundwater, combined with a tax. This dual system performs better than a single instrument because of regional hydrogeological and economic specificities, as well as the fact that it limits costs for farming. We then investigate the impact of alternative combinations of instruments. Our findings show that the most cost-effective and robust way to improve the groundwater state is to increase the economic component (a flexible tax) in association with a flexible quota system.
... Water and land use controls as well as economic instruments are the most common strategies that have been implemented. Examples of these mechanisms are groundwater pumping taxing and pricing (Madani and Dinar, 2013;Mulligan et al., 2014;Stone et al., 2022;, pumping restrictions (Young et al., 2021;Lan et al., 2021;MacEwan et al., 2017;Rodríguez-Flores et al., 2022;, pricing energy (Hrozencik et al., 2022), groundwater markets or water trading mechanisms (Khan and Brown, 2019;Kuwayama and Brozović, 2013;Safari et al., 2023), land fallowing (Van Schmidt et al., 2022) and land management (Bourque et al., 2019;Li et al., 2018;Bryant et al., 2020), implemented individually or utilized in conjunction (Graveline, 2020;Hrozencik et al., 2017). However, most of these studies do not capture the complexity of actually implementing these mechanisms in decision making. ...
... We further test the robustness of the resulting irrigation control policies (Groves et al., 2019;Lempert et al., 2013;Kasprzyk et al., 2013) by assessing how well they perform across a broader sampling of system conditions or states of the world (SOWs). Exploratory modeling-based evaluation of systems' robustness is being used across a broad array complex water management application contexts balancing human demands objectives, economic, sustainability and engineered performance (Graveline, 2020;Huskova, 2016;Miro et al., 2021;Hadjimichael et al., 2020;Shuai et al., 2022;Moallemi et al., 2020;Bertoni et al., 2019;Quinn et al., 2018;Trindade et al., 2019;Shuai et al., 2022). Building off these examples, we identify robust irrigation control policies that consistently achieve performance goals for groundwater depth and economic revenues at the GSA level across a range of challenging SOWs. ...
... HEMs are able to abstract stakeholders decisions (e.g., farmers) and hydrologic dynamics, as well as their feedback, by integrating economic models with hydrologic response functions (Harou et al., 2009). They have played an important role in supporting human and natural systems modeling studies focused on better understanding interdependent economic revenues and aquifer dynamics, as shown by MacEwan et al. (2017), Afshar et al. (2020), Graveline (2020) and Rodríguez-Flores et al. (2022). Additionally, HEMs have proven to be flexible in assisting assessments of the performance of water management policies under different climate scenarios across a range of space and time scales (Partida et al., 2023). ...
Increasing irrigation demand has heavily relied on groundwater use, especially in places with highly variable water supplies that are vulnerable to drought. Groundwater management in agriculture is becoming increasingly challenging given the growing effects from overdraft and groundwater depletion worldwide. However, multiple challenges emerge when seeking to develop sustainable groundwater management in irrigated systems, such as trade-offs between the economic revenues from food production and groundwater resources, as well as the broad array of uncertainties in food-water systems. In this study we explore the applicability of Evolutionary Multi-Objective Direct Policy Search (EMODPS) to identify adaptive irrigation policies that water agencies and farmers can implement including operational decisions related to land use and groundwater use controls as well as groundwater pumping fees. The EMODPS framework yields state-aware, adaptive policies that respond dynamically as system state conditions change, for example with variable surface water (e.g., shifting management strategies across wet versus dry years). For this study, we focus on the Semitropic Water Storage district located in the San Joaquin Valley, California to provide broader insights relevant to ongoing efforts to improve groundwater sustainability in the state. Our findings demonstrate that adaptive irrigation policies can achieve sufficiently flexible groundwater management to acceptably balance revenue and sustainability goals across a wide range of uncertain future scenarios. Among the evaluated policy decisions, pumping restrictions and reductions in inflexible irrigation demands from tree crops are actions that can support dry-year pumping while maximizing groundwater storage recovery during wet years. Policies suggest that an adaptive pumping fee is the most flexible decision to control groundwater pumping and land use.
... The MAPE and is MAE/μ less than 30 percent for all four variables. Moreover, Theil's inequality statistics for all €0.014 per m 3 for water extraction over 1000 m 3 in France (Graveline, 2020) 10 cents increase in water price; a simulation study of South African agricultural water consumption (Letsoalo et al., 2007) (Mehryar et al., 2019) variables show low bias and unequal variation. Such results indicate an unsystematic error (Sterman, 1984;Theil, 1966). ...
... Lately, however, scholars have started focusing on tax policies seeking to improve and preserve the environment. In France, a recent study shows that flexible tax rates can improve groundwater storage (Graveline, 2020). An experimental study demonstrates that taxation can enhance groundwater resources while increasing the net social benefits (Duke et al., 2020). ...
... A simulation study shows that if the South African government increases the water price by 10 African cents per m 3 , agricultural water consumption can be reduced by 6 percent (Letsoalo et al., 2007). In France, all farmers that withdraw more than 1000 m 3 must pay a fixed tax of €0.014 per m 3 for extra water extraction (Graveline, 2020). ...
Benefiting from historically favorable conditions (e.g. low costs, fertile land, and abundant water), pistachio producers in Rafsanjan, Iran, have flourished, with pistachio orchards and production growing dramatically since the 1970s. Today, however, the enormous increase in water consumption associated with pistachio production has severely depleted groundwater aquifers, causing widespread water shortages in the region. In this article, we develop a comprehensive system dynamics model, combining the agronomic, economic, hydrologic, and behavioral aspects to analyze the long‐term implications of pistachio production. Our research contributes to the literature of agricultural water management in three significant ways: (i) it provides a validated and quantitative model exploring pistachio farming for a region; (ii) it explicitly captures behavioral decision rules associated with orchard growth and production investment; and (iii) it addresses a natural common‐pool‐resources problem with very long‐time horizons. We consider several policies aimed at addressing the problem (e.g. water transfers, drip irrigation, financial subsidies, income tax, water pricing, and land purchasing). Our results suggest that policies that increase the effectiveness and efficiency of production (e.g. water transfer and drip irrigation respectively), albeit preferred by farmers, lead to better‐before‐worse results, depleting groundwater storage in the long term. Insights from the model can help policymakers have a better understanding of the unintended consequences of their policies. © 2021 The Authors. System Dynamics Review published by John Wiley & Sons Ltd on behalf of System Dynamics Society.
... This mostly unconfined aquifer is spread between the Seine (northeast) and the Loire (southwest) rivers and constitutes one of the largest groundwater reservoirs in France with an average water stock of 20 billion m 3 and high inter-annual variations (Le Coz, 2000). The Beauce represents the main cereal-producing region in Europe (Graveline, 2020). Its land use consists essentially in agriculture (74%), 50% of which is irrigated. ...
... Indeed, the region is one of the driest in France with an annual average precipitation of 600 mm (Lejars et al., 2012). This results in an intense irrigated farming of between 120 000 and 240 000 ha that withdraws from the groundwater resource between 150 and 450 million m 3 of water per year (Graveline, 2020). The sensitivity of the water resource to natural recharge and the observation of an overall lowering of the water table level since the early 1990s have led to the implementation of several local water policy measures to control water withdrawals in connection with the French Water Law (Légifrance, 1992), which is now the translation of the European Water Framework Directive (European Commission, 2000). ...
The assessment of water travel time through the vadose zone is known to be critical for a proper estimation of the hydrologic response time of water bodies to changes in land use management and global changes. In this study, the hydraulic properties of fifteen samples displaying contrasted lithologies (soil, powdery limestone, calcareous sand, limestone rock) and extracted from three cored boreholes drilled throughout the vadose zone of a vulnerable limestone aquifer were first determined in the laboratory. Three 23 m-deep vadose zone profiles were then reconstituted with the HYDRUS-1D software for the numerical simulation of water flow and the estimation of the water travel time using unimodal and bimodal approaches. The measured hydraulic properties, meteorological and water table level data were used as input for a virtual bromide tracing experiment undertaken over a period of 55 years (1966-2020). The results showed that the experimental hydraulic properties of the samples were more accurately described with a dual porosity approach, since the latter allowed a precise representation of the bimodal characteristic of most of the samples. The water flow and travel time simulated using unimodal or bimodal models for describing the vadose zone hydraulic properties were largely different. The impact of the vadose zone lateral heterogeneities on the simulated water flow and the estimated travel time was relatively limited compared to the influence of the vadose zone vertical heterogeneities and meteorological conditions. The mean travel time of the first concentration, peak concentration and last concentration of bromide simulated with the bimodal model at the maximum water table level of the aquifer was 13.8, 20.9 and 31.5 years, respectively. Increase in travel time was clearly identified since the late 1970s, and could be a consequence of global warming. These results also pointed out the need for conducting extensive studies at larger scales to take into account possible fast transfers of water that might occur through open fractures and karst networks.
... The coefficient is published annually, at the beginning of the year, so groundwater users know in advance the maximum volume of groundwater they can extract that year and can plan their farming activities accordingly. This flexible system has been shown to be economically more beneficial to farmers than a fixed quota system (Graveline, 2020). ...
... Another way to introduce temporal and spatial flexibility in groundwater allocation reductions is to combine a top-down regulatory command and control approach with an economic instrument such as an environmental tax. Graveline (2020) shows that introducing a flexible environmental tax for water use, in association with a flexible allocation cap, is more cost-effective and robust than using a single instrument for groundwater management. This is because the environmental tax reduces the water demand of farms for whom the marginal net benefit of water use is less than the tax. ...
Globally, the agriculture sector is the largest user of groundwater, and to manage declining groundwater resources, reducing groundwater extraction by the agriculture sector is an active policy objective in many jurisdictions. Estimating the cost to agriculture in terms of lost gross margin due to the implementation of exogenously determined water extraction restrictions has been an active research area. This research contributes to the literature on groundwater management by developing a hydro-economic farm optimization model that allows us to internalize the environmental externalities associated with groundwater extraction and compare outcomes with various levels of uniform proportional cuts to agricultural groundwater extraction rights. Our case studies are three sub-areas within Western Australia’s most important groundwater system: the Gnangara Groundwater System. We find evidence that: (i) once environmental externalities are accounted for, the optimal water use by horticulture falls by between 26% and 38% across the three sub-areas; and (ii) compared to a uniform proportional cut policy, spatially and temporally flexible policy mechanisms achieve higher environmental gain with a lower cost to horticulture.
... Empirical analyses of groundwater policies allow the conclusion that their effectiveness and efficiency depends (inter alia) on spatial and temporal flexibility, and on integrating the affected economic agents. For instance, Graveline (2019) found that combining a flexible tax with a flexible quota system can improve the groundwater state in an irrigated agricultural region. She suggested a stepwise introduction and the adjustment of market-based instruments to regional hydrological and economic specificities. ...
... Regulatory and market-based policy instruments have been suggested for effectively managing groundwater resources and climate change adaptation externalities (see, e.g., Graveline 2019;Koundouri 2004;Rey et al. 2019). While we analyze interactions between regional restrictions on groundwater extraction for irrigation and land and water use to inform policy and decision making under climate change scenarios, we do not compare between or evaluate specific groundwater policies. ...
Region-specific groundwater policies are required to regulate groundwater extraction for agricultural irrigation and reduce climate change adaption externalities. We examine the semi-arid Seewinkel region in Austria and explore interactions between climatic, agronomic, hydrological, and socio-economic conditions and processes to provide policy advice. The assessment is conducted with a spatially explicit integrated modeling framework to analyze impacts on land and irrigation water use, land management, and net benefits of agricultural production. The model results show that with imposed groundwater restrictions for irrigation, land use shifts from irrigated vineyards to mostly rainfed cropland with declining regional net benefits of agricultural production. The direction of change is similar for a DRY, SIMILAR, and WET climate scenario, while the magnitude differs. We estimate that an increase of the marginal value of groundwater extraction for irrigation by 0.1 €/m³ results in an average decrease in groundwater extraction volumes by 17.2 Mm³ in DRY, 6.3 Mm³ in SIMILAR, and 6.4 Mm³ in WET. Furthermore, regional net benefits of agricultural production decrease by 3.4 M€ in DRY and SIMILAR, and by 1.6 M€ in WET, on average. Our assessment highlights that efficient groundwater policies can help to sustain groundwater availability in semi-arid regions, particularly under climate change.
... Robust decision making is a method that uses results from several simulation runs (using alternative models and/or scenarios through scenario-discovery techniques) to connect policy makers with model(s) capable of exploring uncertainty, so to identify robust adaptation options as those that "perform well compared to alternatives" (Marchau et al., 2019) and "hedge against uncertainty" (Graveline, 2019). Robust decision making process typically follows an iterative process between researchers and stakeholders/policy makers in five steps (Marchau et al., 2019). ...
... We started by using constrained optimization methods through the utilization of the Minimization of Maximum regret algorithm (MinMax regret). Min-Max regret measures regret as "the distance between the indicator for an instrument and the best indicator in a given scenario" (Graveline, 2019). ...
The Piedmont Region in NW Italy has recently deployed an ambitious and pioneering agricultural water pricing reform aimed at integrating and effectively enforcing EU's Water Framework Directive principles of cost recovery, polluter-pays and affordability. This paper develops a multi-model ensemble framework encompassing 5 mathematical programming models (2 Positive Mathematical Programming models, 2 Positive Multi-Attribute Utility Programming models and 1 Weighted Goal Programming model) that represent the observed behavior of socioeconomic agents to: 1) simulate the impacts of the Piedmontese water pricing reform on land use allocation and management, water conservation, profit and water tariff revenue; 2) sample modeling uncertainty through the ensemble spread; and 3) explore potential tipping points through use of scenario-discovery techniques. Our research suggests that the key challenge to the reform lies in the management of rice fields, an extensive (17% of the agricultural area), water-demanding and relatively low-added-value crop that nonetheless delivers significant ecosystem services (e.g. water retention) of historical and cultural relevance to the region. The ensemble experiment suggests that rice agriculture rapidly dwindles in the price range 0.012–0.074 EUR/m3 depending on the model. Before reaching this tipping point, agricultural water pricing can reduce withdrawals up to 1.7%–9.5%, while reducing profit between 4.9% and 5.6% and achieving a 57- to 65-fold increase in water tariff revenue.
... For example, flexible quotas function as dynamic tools that adapt to changing circumstances, introducing elasticity into traditionally rigid mechanisms such as water concessions (Lange et al., 2023). This approach involves annually reviewing water allocations to ensure they do not exceed the capacity of the available water sources (Graveline, 2020). While these share similarities with existing demand regulations, lack of enforcement hampers their effective implementation. ...
Study region: The Guachal River Basin (GRB), a headwater of the Cauca River in Colombia's Tropical Andes. Study focus: Droughts develop gradually, without clear time-space boundaries, affecting extensive geographical areas. When droughts occur, they exacerbate existing water scarcity, aggravating the negative impacts on vulnerable populations and ecosystems. The drivers of these phenomena are complex, ranging from natural to anthropogenic, and their impacts are cumulative and not structural. This research investigates the socio-natural dynamics of drought and water scarcity in the GRB. We explore these dynamics through secondary data review and stakeholder interviews, capturing perceptions and manifestations of droughts beyond official reported data. The Drivers-Response-Impacts framework is employed to unravel these complexities and offer insights to improve drought and water management. New hydrological insights for the region: Our research reveals that water scarcity in the GRB primarily results from land use changes and water overconsumption by the local elite, who have transitioned to sugarcane farming. ENSO-driven droughts further exacerbate water shortages in the GRB. Policy responses to drought and water scarcity are often ineffective and reactive, addressing only immediate symptoms rather than long-term drivers, such as the role of the elite in perpetuating scarcity. We explore several strategies to enhance water management: exploring new drought indicators, creating comprehensive drought damage inventories, implementing adaptable demand control mechanisms targeting high-volume users, and enhancing stakeholder participation in decision-making processes.
... studies quantified uncertainties in either human or water systems). While integrated human-water system models (including DSSs) abound in the literature (Baccour et al., 2022;Graveline, 2020;Gil-García et al., 2023;Li et al., 2020;Martínez-Dalmau et al., 2023;Pande and Sivapalan, 2017;Ward, 2021) and examples of model intercomparison experiments (e.g. HEPEX, 2024) and sensitivity analyses do exist (Puy et al., 2022;Saltelli, 2019), particularly in wa-ter systems, in practice water resource modelling (including DSSs for planning and management) ignores uncertainties within and across water and/or human systems (OECD, 2021). ...
This paper develops an actionable interdisciplinary model that quantifies and assesses uncertainties in water resource allocation under climate change. To achieve this objective, we develop an innovative socio-ecological grand ensemble that combines climate, hydrological, and microeconomic ensemble experiments with a widely used decision support system for water resource planning and management. Each system is populated with multiple models (multi-model), which we use to evaluate the impacts of multiple climate scenarios and policies (multi-scenario, multi-forcing) across systems so as to identify plausible futures where water management policies meet or miss their objectives and to explore potential tipping points. The application of the methods is exemplified by a study conducted in the Douro River basin (DRB), an agricultural basin located in central Spain. Our results show how marginal climate changes can trigger non-linear water allocation changes in the decision support systems (DSSs) and/or non-linear adaptive responses of irrigators to water shortages. For example, while some irrigators barely experience economic losses (average profit and employment fall by < 0.5 %) under mild water allocation reductions of 5 % or lower, profit and employment fall by up to 12 % (∼ 24 ×) when water allocation is reduced by 10 % or less (∼ 2×). This substantiates the relevance of informing the potential natural and socio-economic impacts of adaptation strategies and related uncertainties for identifying robust decisions.
... Fleksibilna kvota predstavlja regulatorni instrument i ona se koristi u kombinaciji sa ekonomskim instrumentima u vidu poreza na vodu. Ovaj porez se naplaćuje svim poljoprivredncima koji koriste više od 1000 m 3 vode za navodnjavanje, a njegov cilj je sprečavanje ili sanacija štete nanete životnoj sredini (Graveline, 2020). Kombinacija oba instrumenta se pokazala uspešna u zaštiti životne sredine, zato što porez deluje kao podsticaj za racionalno korišćenje vode, a fleksibilna kvota značajno smanjuje troškove poljoprivrednika u odnosu na fiksnu. ...
Ever since the industrial revolution, environmental pollution and the exploitation of natural resources have been growing exponentially. Water pollution stands out among today's numerous global environmental problems due to its topicality and crucial impact on human life. The three most important sectors of water consumption today are agriculture, industry, and domestic consumption. Agriculture is by far the largest consumer of water - accounting for almost two-thirds of the world's demand. The constant increase in world population and growth of living standards on a global scale are the main factors, along with processes such as extensive urban development, that cause an increase in the global need for water. This trend is most visible in developing countries where water pollution is widespread due to the rapid development of industry and agriculture, which increases the problem of an adequate supply for the population. At the same time, these countries are experiencing a demographic explosion and are experiencing significant economic progress. Many economic instruments and policies of pollution control that have their origins in the economic theory, whose main function is the internalization of externalities, have found their successful application in this field as well, although they have not been given the attention they deserve for some time. In practice, those instruments and policies that are based on incentives, or market-based, such as various types of taxes, fees, and subsidies, have proven to be particularly effective. Various problems in water management in Europe required individual countries to find the most appropriate pollution control policies. This paper analyzes the characteristics and scope of certain economic instruments and positive examples of European countries that have implemented them in their legal frameworks in an attempt to improve water protection. Their specific experiences, in addition to indicating how far behind the best European practice we are, represent very useful guidelines for the adequate application of economic instruments in the Republic of Serbia. The existing laws in this area are outdated, as the main instruments are used in a system of fines and different standards that have no potential to encourage a change in the awareness of end users and, as such, they do not represent a good basis for improving sustainable water management.
... There is a large number of publications on economic instruments [11,13,16,[36][37][38][39][40], their performance [17,41], their association with harmful subsidies [42][43][44], and their implementation in relation to environmental components [45][46][47], such as biodiversity and ecosystem services [19,48], and their use on diverse economic sectors [49,50]. Likewise, there are various publications on the financing programs of the EU, specifically regarding their use, evaluation, and implementation since they were created [25,49,[51][52][53]. ...
Economic instruments are political tools created to promote environmental stewardship by influencing consumption and production patterns, fostering technological innovation, and improving the environment; however, if current failures in their formulation or implementation persist, they can negatively impact the environment and society. This research aims to analyze the strengths, weaknesses, opportunities, and threats (SWOT) of economic instruments by extracting these aspects from the forest policy documents of the EU, Austria, and the Czech Republic using the qualitative content analysis method. It has been found that the EU channels its resources from economic instruments through various financing programs that make distribution more effective and align with the environmental objectives of the EU. Additionally, the SWOT analysis indicates that the economic instruments applied in the EU present significant differences in the application and management of forests and the performance of the financial instruments according to the national strategies and action plans used. These identified challenges, limitations, and improvement areas allow for generating suggestions that policymakers can apply concerning the use, implementation, dissemination, and access processes of financing mechanisms for sustainable forest management in the European Union.
... In the fourth stage (tradeoff analysis), analysts and parties to the decision identify the strategy that performs better in terms of robustness, i.e. the strategy that provides "better tradeoffs than the existing alternatives" (Marchau et al., 2019). This can be done following i) automated constrained optimization procedure, such as minimization of maximum regret (MinMax regret) or identification of the best worst-case output value (Maximin) (Graveline, 2019); ii) expert judgment, which complements results from exploratory modeling with heuristic methods to decide on the strategy to adopt (Lempert and Groves, 2010); or iii) a combination of both approaches that uses automated procedures to guide experts judgments, as was done in this research. ...
The contribution of this paper is twofold: 1) it develops a replicable socio-hydrology-inspired model that elicits agents' preferences while accounting for the two-way feedbacks between complex human and water systems; and 2) it integrates the resultant socio-hydrology model into robustness-based frameworks to inform the adoption of policies that show a satisfactory performance under most plausible futures. The socio-hydrology model is used to produce a database representing multiple plausible futures that quantifies uncertainty regarding scenario assumptions under alternative adaptation strategies. Using a robust decision-making framework, the mechanistic outputs from the database of plausible futures are combined with heuristic methods through experts' knowledge and opinion to co-design scenarios, identify vulnerabilities and quantify tradeoffs of proposed strategies, and subjectively propose new scenarios and choose the preferred adaptation strategy. Methods are illustrated with an application to the Cega Catchment in central Spain, one of the few major catchments in central Spain that remains non-regulated, and where the construction of a major dam has been projected. Following a robust decision-making process informed by our socio-hydrology model and involving all key parties to the decision, the status quo strategy (no dam construction) was revealed preferred.
... The thickness and the topography of the Beauce limestone aquifer ranges from 10 to 200 m and from 70 m up to 190 m [105]. The Beauce represents the main cereal-producing region in Europe [106] and its land use consists essentially in agriculture (74%), 50% of which is irrigated [107]. Over the past decades, this intensive agricultural activity have led to the implementation of governmental policies and regulatory measures whose actions aim at controlling water withdrawals [108,109] and preserving groundwater quality, particularly towards pesticides and nitrates contaminations [110,111]. ...
The structure and dynamics of the Vadose Zone (VZ) play a major role in the groundwater recharge process and in the transport of contaminants. By monitoring the mass and heat transfer processes within the VZ, it will be possible to predict the contaminants travel time and implement suitable solutions to preserve the groundwater resources. Several environmental monitoring solutions have been developed in recent years to better understand the complex hydrogeological processes that occur along the VZ. The use of Fiber Optic (FO) sensors is a promising technology for environmental monitoring. Compared to conventional sensors, the FO sensors allow measuring and monitoring different parameters, while offering interesting specificities. To improve our knowledge on the reactive processes occurring during mass and heat transfers within the VZ of the Beauce aquifer, the Observatory of transfers in the VZ is being developed near Orléans (France). Three types of distributed FO sensors (DTS, DSS and DAS) have been installed at the O-ZNS experimental site in July 2020. This chapter presents the state of the art on the use of FO sensors for environmental monitoring. The installation of these sensors at the O-ZNS site is then discussed along with the future developments and targeted results.
... Modeling efforts have explored the dynamics and feedbacks of food-water systems using hydro-economic modeling approaches (Harou et al. 2009), factoring the particular characteristics of water and agricultural production systems. Various studies have used modular and response functions coupling taxonomies to represent the coevolution of agricultural production systems with surface water systems (Giuliani et al. 2016;Forni et al. 2016;Maneta et al. 2020) and groundwater systems (Graveline 2019;Afshar et al. 2020;MacEwan et al. 2017), to assess impacts of exogenous changes and water policies. ...
Assessing impacts on coupled food-water systems that may emerge from water policies, changes in economic drivers and crop productivity requires an understanding of dominant uncertainties. This paper assesses how a candidate groundwater pumping restriction and crop prices, crop yields, surface water price, electricity price, and parametric uncertainties shape economic and groundwater performance metrics from a coupled hydro-economic model (HEM) through a diagnostic global sensitivity analysis (GSA). The HEM used in this study integrates a groundwater depth response, modeled by an Artificial Neural Network (ANN), into a calibrated Positive Mathematical Programming (PMP) agricultural production model. Results show that in addition to a groundwater pumping restriction, performance metrics are highly sensitive to prices and yields of perennial tree crops. These sensitivities become salient during dry years when there is a higher reliance on groundwater. Furthermore, results indicate that performing a GSA for two different water baseline conditions used to calibrate the production model, dry and wet, result in different sensitivity indices magnitudes and factor prioritization. Diagnostic GSA results are used to understand key factors that affect the performance of a groundwater pumping restriction policy. This research is applied to the Wheeler Ridge-Maricopa Water Storage District located in Kern County, California, region reliant on groundwater and vulnerable to surface water shortages.
... In most arid and semi-arid regions, groundwater levels fall due to droughts and over-exploitation, causing an accumulated negative water balance and subsequent land subsidence. One of the approaches to deal with groundwater over-exploitation is to impose penalties for the violation of water rights (Montginoul et al. 2016;Graveline 2020). Iran's groundwater resources are subject to farmers' over-exploitation. ...
One strategy to deal with unauthorized groundwater withdrawals (which is mainly done by farmers) is to impose penalty policy by the government. Since farmers' over-exploitation is subject to social, economic, cultural, and agricultural condition of the region, feedback assessment of penalty patterns based on a socio-economic simulation is indispensable. This study presents an agent-based framework to study the interaction of agricultural, environment, and regulator agents within an agricultural system. The behavior of agricultural sector was simulated in two levels: i) agricultural sub-agents and ii) agricultural group-agents. For agricultural sub-agents, individual benefit was maximized under behavioral and physical constraints simulated by Fuzzy Inference System (FIS) and mathematical programing. For agricultural agents, a linked linear optimization and Non-dominated Sorting Genetic Algorithm (NSGA-II) was adopted to identify best solution from the agricultural sector view point. The proposed framework was implemented in Najaf Abad hydrological unit situated in Isfahan province, Iran, considering fixed and stepwise penalty approaches. Sensitivity analysis on the amount of base penalty in the fixed penalty scenario indicated that under 0.12 United States $ per cubic meter penalty enforcement, the annual over-exploitation reduced from the current 79 Million Cubic Meter (MCM) to zero. Furthermore, the results indicated that if the width of the step increased from 1 to 9 MCM/yr, the over-exploitation also increased by about 18 MCM/yr.
... Much HEA has been conducted for European watersheds (Alamanos et al., 2019;Alamanos et al., 2021;Blanco-Gutierrez et al., 2013;Carolus et al., 2020;Escriva-Bou et al., 2017;Graveline, 2020;Heinz et al., 2007;Herivaux et al., 2013;Hervas-Gamez and Delgado-Ramos, 2020;Koch and Grunewald, 2009;Molina et al., 2013;Pena-Haro et al., 2009;Pulido-Velazquez et al., 2008;Ruperez-Moreno et al., 2017;Udias et al., 2016). Some of Europe's best known contributions have come from Spain that has a long history of climate stress and intense competition for water (Blanco-Gutierrez et al., 2013;Crespo et al., 2019;Essenfelder et al., 2018;Kahil et al., 2015;Kahil et al., 2016;Lopez-Nicolas et al., 2018;Perez-Blanco et al., 2021;Ruperez-Moreno et al., 2017;Varela-Ortega et al., 2016;Varela-Ortega et al., 2011). ...
Climate water stress internationally challenges the goal of achieving food, energy, and water security. This challenge is elevated by population and income growth. Increased climate water stress levels reduce water supplies in many river basins and elevate competition for water among sectors. Organized information is needed to guide river basin managers and stakeholders who must plan for a changing climate through innovative water allocation policies, trade-off analysis, vulnerability assessment, capacity adaptation, and infrastructure planning. Several hydroeconomic models have been developed and applied assessing water use in different sectors, counties, cultures, and time periods. However, none to date has presented an optimization framework by which historical water use and economic benefit patterns can be replicated while presenting capacity to adapt to future climate water stresses to inform the design of policies not yet been implemented. This paper's unique contribution is to address this gap by designing and presenting results of a hydroeconomic model for which optimized base conditions exactly match observed data water use and economic welfare for several urban and agricultural uses at several locations in a large European river basin for which water use supports a population of more than 3.2 million. We develop a state-of-the arts empirical dynamic hydroeconomic optimization model to discover land and water use patterns that optimize sustained farm and city income under various levels of climate-water stress. Findings using innovative model calibration methods allow for the discovery of efficient water allocation plans as well as providing insight into marginal behavioral responses to climate water stress and water policies. Results identify that water trade policy under climate water stress provides more economically efficient water use patterns, reallocating water from lower valued uses to higher valued uses such as urban water. The Ebro River Basin in Spain is used as an example to investigate water use adaptation patterns under various levels of climate water stress. That basin's issues and challenges can be of relevance to other river basins internationally.
... In most arid and semi-arid regions, groundwater levels fall due to droughts and over-exploitation, causing an accumulated negative water balance and subsequent land subsidence. One of the approaches to deal with groundwater over-exploitation is to impose penalties for the violation of water rights (Montginoul et al. 2016;Graveline 2020). Iran's groundwater resources are subject to farmers' over-exploitation. ...
One strategy to deal with unauthorized groundwater withdrawals by farmers is to impose penalties. Because farmers’ over-exploitation is subject to social, economic, cultural, and agricultural characteristics of the region, feedback assessments of a penalty policy using socio-economic simulation is indispensable. This study presents an agent-based framework to study the interaction among agricultural, environmental, and regulator agents within an agricultural system. The behavior of the agricultural sector was simulated at two levels: agricultural sub-agents, and agricultural group-agents. For agricultural sub-agents, individual benefit was maximized under behavioral and physical constraints simulated by a fuzzy inference system (FIS) and mathematical programing. A coupled linear optimization and nondominated sorting genetic algorithm (NSGA-II) were adopted to identify the best solution, from the agricultural sector’s viewpoint. The proposed framework was implemented in the Najaf Abad hydrological unit, situated in Isfahan province, central Iran, considering fixed and stepwise penalty approaches. Sensitivity analysis of the amount of base penalty in the fixed penalty scenario indicated that, under a $0.12 per cubic meter penalty, the annual over-exploitation declined from the current 79 million cubic meters (MCM) to zero. Furthermore, the results indicated that if the width of the step increased from 1 to 9 MCM/year, the over-exploitation increased by about 18 MCM/year.
... Well-managed irrigation emerges as a viable and indispensable resource to ensure high yields and diversification of agricultural production (Borghetti et al., 2017;Saath & Fachinello, 2018;Fontenelle, 2019;Chen et al., 2020), reducing risks of food insecurity. However, when irrigation is performed without proper technical criteria, the pressure on natural resources increases, causing environmental and socioeconomic impacts, which makes the activity unsustainable (Gibson et al., 2018;Graveline, 2020;Li et al., 2020a). ...
When performed without technical criteria, the rapid expansion of irrigated agricultural frontiers can result in overexploitation of water, causing worrying impacts on the balance of agroecosystems. This study proposes a model applied to the state of Bahia, to estimate the water demand of areas irrigated by a central pivot, in order to contribute to information that will subsidize the inspection and planning of water resources in the promotion of sustainable agriculture. The irrigated areas were identified and measured by photointerpretation using orbital images from the Landsat-8 satellite. With a historical series of data, the reference evapotranspiration was calculated and monthly water balance was elaborated. The data obtained were spatialized by kriging, and with punctual values of water deficit (mm), the water demand of the irrigated perimeter of the equipment was estimated. The results were described considering strategic planning units, proposed from municipalities, hydrographic basins and biomes. A total of 4075 pivots were quantified, covering an irrigated area of 265,896.30 ha and with an average annual consumption of 1,333,473,208.02 m³ of water. Areas of high demand were identified, especially in the western region of Bahia, which includes the hydrographic basin of the São Francisco River and the Cerrado biome, concentrating 80.85% and 75.47% of the state water demand for pivots, respectively. Considering possible points of water vulnerability and continuity of this expansion, the results provide the primary information needed to encourage the adoption of public policies aimed at the management of water resources. The study method proposes guidelines that condition the application in any region of interest in the world.
Graphical abstract
... Several very recent works in 2020 alone from many places internationally have looked at climate adaptation challenges (Alamanos et al., 2020;Baah-Kumi and Ward, 2020;Burek et al., 2020;Carolus et al., 2020;Dawoud, 2020;Do et al., 2020;Exposito et al., 2020;Goncalves et al., 2020;Graveline, 2020;Konapala and Mishra, 2020;Maneta et al., 2020;Meng et al., 2020;Pakhtigian et al., 2020;Sabbaghi et al., 2020;Slater et al., 2020;Tran et al., 2020;Turner et al., 2020). ...
Successful climate adaptation needs to sustain food, water, and energy security in the face of elevated carbon emissions. Hydroeconomic analysis (HEA) offers considerable potential to inform climate adaptation plans where water is an important element of economic activity. This paper's contribution is to identify how HEA can inform climate adaptation plans by minimizing economic costs of responding to climate induced changes in water supplies. It describes what HEA is, why it is important, how researchers implement it, who has made significant contributions, and places where it has informed policy debates. It also describes future directions for the use of HEA to guide climate adaptation.
... For example, increased pumping during drought years could result in acute aquifer depletion, exacerbating issues such as reduction of baseflow to hydrologically connected freshwater (Condon & Maxwell, 2019;Palazzo & Brozović, 2014;Perkin et al., 2017) that is sensitive to the distribution and timing of groundwater pumping. We argue that design of groundwater allocation policies therefore entails trade-offs between hydrologic and economic outcomes, which have been neglected in prior research analyzing the performance of aquifer management policies such as water use quotas (Graveline, 2020;Guilfoos et al., 2016;Hrozencik et al., 2017;Kahil et al., 2016;Khan & Brown, 2019;Kuwayama & Brozović, 2013;Madani & Dinar, 2013;Mulligan et al., 2014;Palazzo & Brozović, 2014). ...
A common environmental externality of groundwater pumping is streamflow depletion. To manage impacts of groundwater pumping on hydrologically connected surface water systems, regulators often impose quotas, or allocations, limiting the rates of groundwater extraction. Allocations vary in their temporal flexibility, ranging from single‐year “hard caps” to multi‐year “soft caps”. Soft cap allocations allow greater flexibility for farmers, the primary users of groundwater, to adjust irrigation rates from one year to another, potentially providing greater resilience to drought but also altering hydrologic impacts of pumping. In this study, we integrate agronomic, economic, and hydrologic models to evaluate optimal irrigation decisions for a range of equivalent hard and soft cap limits, and assess trade‐offs between the resulting economic (farm profitability) and hydrologic (stream depletion) outcomes. Soft cap allocation policies consistently outperform equivalent hard caps in terms of greater farm profitability and reduced production risks. However, the economic benefits of soft caps come at the cost of higher peak and cumulative rates of streamflow depletion, with the magnitude of differences dependent on aquifer properties, well location, and the length of the soft cap allocation period. Our findings suggest that the optimal allocation design will depend on competing socioeconomic and environmental objectives, and, in some instances, may require a blended approach to efficiently achieve desired management goals.
... While standard hydro-economic models are well suited to answer the question "who should get the water, so benefits are maximized", another entirely different question is "how" to translate a model solution to real decisions. Water resources management has developed several regulatory and economic instruments for water policy implementation, including watershed plans, water permits, water charges and markets, water quality standards, among others (Cross & Latorre, 2015;Graveline, 2019;OECD, 2015a). However, the instruments' implementation, coordination, and change to meet current and future policy goals are still limited in several regions and countries (OECD, 2015a). ...
Increasing scarcity and pollution has called for changes in water policies, which should reflect society's preferences toward water use, development, and the environment. Water management is still limited in incorporating changing policies and in deriving directives to implement water instruments under long‐term planning. Some examples are water charges that do not reflect watershed externalities and water permits lacking future vision of allocation. Hydro‐economic modeling has explored trade‐offs of water allocation and improved water operations but still does not address instruments' integration. This paper proposes a modeling approach that identifies how to apply water management instruments integrated with each other to deliver a water allocation strategy reconciled with economic development projections and changing water use preferences. This improves our understanding on adjusting the implementation of water management instruments considering future outcomes and trade‐offs. The methodology combines discrete dynamic programming to determine increments in water permits, multiobjective linear programming to generate a Pareto set to model users' water preferences, and nonlinear programming to allocate water permits over different river reaches subject to water quality targets. The reconciliation allowed to identify sustainable water allocation strategies supported by a watershed, and instruments' integration to make it feasible. Strategies imposing limited water permits to economic users and watershed regions indicated where (and when) water conservation programs should be applied, along with quantitative targets (how much). The economic trade‐offs identified reference values for economic instruments to compensate the externalities. Finally, less strict water quality targets did not result in higher economic returns.
... Some works point to the development of measures to control demand so that irrigation water sustainability can be reached. The development of efficient water markets can be an optimal measure in underdeveloped areas and with a high level of water scarcity, like in South Africa [19,20]. The implementation of joint restrictions based on the establishment of quotas and the payment of fees can be an effective control system for the use of agriculture water in developed regions specialized in the production of high-quality crops and where overexploitation of water resources is currently taking place [21]. ...
Irrigated agriculture plays a fundamental role as a supplier of food and raw materials. However, it is also the world's largest water user. In recent years, there has been an increase in the number of studies analyzing agricultural irrigation from the perspective of sustainability with a focus on its environmental, economic, and social impacts. This study seeks to analyze the dynamics of global research in sustainable irrigation in agriculture between 1999 and 2018, including the main agents promoting it and the topics that have received the most attention. To do this, a review and a bibliometric analysis were carried out on a sample of 713 articles. The results show that sustainability is a line of study that is becoming increasingly more prominent within research in irrigation. The study also reveals the existence of substantial differences and preferred topics in the research undertaken by different countries. The priority issues addressed in the research were climatic change, environmental impact, and natural resources conservation; unconventional water resources; irrigation technology and innovation; and water use efficiency. Finally, the findings indicate a series of areas related to sustainable irrigation in agriculture in which research should be promoted.
The purpose of this paper is to disclose the social cause and effect links of the development of the agrarian AI economy and to determine the prospects for its sustainable development, i.e. optimisation of its social implications through change management. Based on the international statistics for 2022 and using the methods of regression, correlation, and trend analysis, we prove that, in combination with electronic infrastructure, expanded capabilities of the AI economy for social communications allow optimising its implications, i.e. ensuring its sustainable development. The paper's originality consists in a reconsideration of the agrarian AI economy from the position of society and description of its previously unknown—social—nature, and the development of a new approach to its sustainable development. The practical significance of the paper is that the developed approach to the management of the development of the agrarian AI economy will allow raising the effectiveness of this management and will maximise its contribution to the increase in the population’s quality of life and strengthening of food security. The scientific novelty of the authors’ conclusions lies in their discovering the essential difference between the social implications of the development of the AI economy in agriculture and these implications in other sectors. The research results showed that, unlike most other spheres, the development of the AI economy leads to an aggravation of social risks but to the creation of social advantages in agriculture. Given this conclusion, a unique approach for agriculture to sustainable development in the AI economy was developed—not through limitation but through stimulation of digitalisation with particular attention to technological support for the optimisation of social communications.
This paper develops an actionable interdisciplinary model that thoroughly quantifies and assesses uncertainties in water resources allocation under climate change. To achieve this objective, we develop an innovative socio-ecological grand ensemble that combines climate, hydrological, and microeconomic ensemble experiments with a widely used Decision Support System for water resources planning and management. Each system is populated with multiple models (multi-model), which we use to evaluate the impacts of multiple climatic scenarios and policies (multi-scenario, multi-forcing) across systems, so as to identify plausible futures where water management policies meet or miss their objectives, and explore potential tipping points. The application of methods is exemplified through a study conducted in the Douro River Basin (DRB), an agricultural basin located in central Spain. Our results show how marginal climate changes can trigger nonlinear water allocation changes in the Decision Support Systems (DSS); which can be further aggravated by the nonlinear adaptive responses of irrigators to water shortages. For example, while some irrigators barely experience economic losses (average profit and employment fall by <0.5 %) under mild water allocation reductions of 5 % or lower, profit and employment fall up to 12 % (~24x more) where water allocation is reduced by 10 % or less (~2x more). This substantiates the relevance of informing on the potential natural and socioeconomic impacts of adaptation strategies, and related uncertainties, towards identifying robust decisions.
Irrigation expansion driven by a growing global food demand is threatening the sustainability of scarce water resources. An exemplar is the Ica Valley in Peru which has experienced significant agricultural transformation over the last three decades with uncontrolled abstractions leading to over-exploitation of the Ica-Villacuri aquifer. This paper critically assesses the impacts of agricultural expansion on the long-term sustainability of groundwater resources in the Ica Valley. We apply a combination of spatial analysis and irrigation modelling by farming type (large and small-scale), followed by a multi-criteria assessment on irrigation water use. Historical trends in cropped area were analysed using Landsat satellite imagery to identify agricultural expansion and the changing composition between large and small-scale farms. The blue water footprint (WFblue) for croplands was calculated distinguishing between surface and groundwater abstractions for eight disaggregated geographical zones within the Ica Valley. The economic benefits of water consumption were assessed using the water productivity indicator, and the environmental sustainability of water resources spatially evaluated using a monthly blue water sustainability index and adapted version of the groundwater debt. The analyses showed that the groundwater footprint accounts for 87% of the total WFblue (483 Mm³) with 286 Mm³ groundwater consumed under unsustainable conditions (exceeding groundwater recharge). The highest water productivity (2.4-5.4 sol/ton) occurs in zones with intensive groundwater abstractions and where most large-farms are located, but it is also where the sustainability issue is most acute. Modelling showed that based on existing climate conditions and cropping patterns, irrigated agriculture is locally unsustainable throughout the valley, with the exception of small-scale farming in the peri-urban and middle valley areas. Around 10% of total aquifer recharge results from small-scale irrigated farming, whereas recharge from large scale farming is negligible. The greatest impacts occur in zones dominated by large-scale farms, where a period of 3.7 to 5.9 years is estimated to be needed to replenish water resources consumed by agricultural production. There is thus an urgent need to manage water resources more effectively and promote more sustainable use of water to protect both traditional and agro-export agricultural practices as well as allocations for urban water supply and the environment.
Con la finalidad de brindar información sobre el impacto de las iniciativas económicas vinculadas a atenuar los daños ambientales, el presente documento contiene revisión bibliográfica de los últimos 5 años sobre instrumentos económicos (pago por servicios ecosistémicos e impuestos ambientales) empleados en la mitigación del sobreuso de recursos hídricos. Así mismo clasifica diversos estudios de valoración economía en relación a la metodología que emplean para valorar determinados servicios ecosistémicos provistos por los recursos hídricos. Los que diseñan políticas públicas al implementar impuestos ambientales dirigidos a determinados niveles de consumo deben considerar aspectos cómo la acumulación de la contaminación para garantizar la sostenibilidad del suministro de servicios ecosistémicos. Incluir los valores obtenidos en valoración económica en el análisis costos – beneficio puede ayudar en la toma de decisiones de inversión en restauración o recuperación del capital natural.
A growing number of countries are reforming their water allocation regimes through the use of economic instruments. This article analyzes the performance of economic instruments in water allocation reforms compared against their original design objectives in five European countries: England, France, Italy, Spain and the Netherlands. We identify the strengths of, barriers to and unintended consequences of economic instruments in the varying socio-economic, legal, institutional and biophysical context in each case study area, and use this evidence to draw out underlying common guidelines and recommendations. These lessons will help improve the effectiveness of future reforms while supporting more efficient water resources allocation.
Shaping global change adaptation strategy in water resource systems requires an interdisciplinary approach to deal with the multiple dimensions of the problem. The modelling framework presented integrates climate, economic, agronomic and hydrological scenarios to design a programme of adaptation measures at the river basin scale. Future demand scenarios, combined with a down-scaled climate scenario, provide the basis to estimate the demand and water resources in 2030. A least-cost river basin optimisation model is then applied to select adaptation measures ensuring that environmental and supply management goals are achieved. In the Orb river basin (France), the least-cost portfolio selected suggests mixing demand and supply side measures to adapt to global change. Trade-offs among the cost of the programme of measures, the deficit in agricultural water supply and the level of environmental flows are investigated. The challenges to implement such interdisciplinary approaches in the definition of adaptation strategies are finally discussed.
We develop a programming model of crop production to predict the effects of environmental policies on agriculture and the environment. The model is calibrated against acreages, yields, and exogenous supply elasticities following positive mathematical programming. In addition, crop production functions are calibrated to yield elasticities with respect to nitrogen and irrigation obtained from a biogeochemical model. We study the effects of a nitrogen tax in Yolo County, California, intended to mitigate nitrogen pollution from field crops. The behavioral and environmental responses to the tax are largely due to intensive margin adjustments. Sizable reductions in nitrate leaching are achieved at a low social cost.
This study presents an analysis of climate-change impacts on the water resources of two basins located in northern France, by integrating four sources of uncertainty: climate modelling, hydrological modelling, downscaling methods, and emission scenarios. The analysis focused on the evolution of the water budget, the river discharges and piezometric heads. Seven hydrological models were used, from lumped rainfall-discharge to distributed hydrogeological models, and led to quite different estimates of the water-balance components. One of the hydrological models, CLSM, was found to be unable to simulate the increased water stress and was, thus, considered as an outlier even though it gave fair results for the present day compared to observations. Although there were large differences in the results between the models, there was a marked tendency towards a decrease of the water resource in the rivers and aquifers (on average in 2050 about −14 % and −2.5 m, respectively), associated with global warming and a reduction in annual precipitation (on average in 2050 +2.1 K and −3 %, respectively). The uncertainty associated to climate models was shown to clearly dominate, while the three others were about the same order of magnitude and 3–4 times lower. In terms of impact, the results found in this work are rather different from those obtained in a previous study, even though two of the hydrological models and one of the climate models were used in both studies. This emphasizes the need for a survey of the climatic-change impact on the water resource.
A global water model is used to analyse the impacts of climate change and socio-economic driving forces (derived from the A2 and B2 scenarios of IPCC) on future global water stress. This work extends previous global water research by analysing not only the impact of climate change and population, but also the effects of income, electricity production, water-use efficiency and other driving forces, on water stress. Depending on the scenario and climate model, water stress increases (between current conditions and the 2050s) over 62.0–75.8% of total river basin area and decreases over 19.7–29.0% of this area. The remaining areas have small changes. The principal cause of decreasing water stress (where it occurs) is the greater availability of water due to increased annual precipitation related to climate change. The principal cause of increasing water stress is growing water withdrawals, and the most important factor for this increase is the growth of domestic water use stimulated by income growth. (Population growth was a much less important factor and irrigated area was assumed to remain constant.) To address the uncertainty of water stress estimates, three different indicators of water stress were computed and compared. The overlap area of their computation of “severe stress” in the 2050s was large (approximately 23 × 10 km or 56–73 % of the total “severe stress” area). This indicates a moderate level of agreement and robustness in estimates of future water stress. At the same time the indicators disagreed in many other areas, suggesting that work is still needed to elaborate general indicators and concepts of water stress.
This paper revisits Gisser-Sanchez's effect, a paradoxical empirical result that persists in the groundwater literature since 1980, when it was first identified by Gisser and Sanchez. In essence, Gisser-Sanchez's effect (GSE) states that the numerical magnitude of benefits of optimally managing groundwater is insignificant. This paper critically reviews both the theoretical and empirical attempts to address GSE. It highlights the fact that in the theoretical literature the single most important cause for the presence of GSE is the prevalence of very steep marginal groundwater use benefit curves, which imply that groundwater usage is not very sensitive to price changes. However there exist circumstances that its effects can be eliminated. Thus the case for different theoretical investigations is put forward. Moreover, this paper also points at various misconceptions, inaccuracies, and omissions of the current state of the literature that could potentially resolve part of the existing puzzle.
We downscaled 12 scenarios of anthropogenic climate change in the basins of the Seine and Somme Rivers (France). They were used as input to 5 different hydrological models. This framework allowed us to quantify the different sources of uncertainty. The resulting hydrological scenarios agree on a marked depletion of water resources during the 21 st century with an annual mean decrease in both water table level and river discharge. At the seasonal scale, the reduction of river flow is more marked on low than on high flows, the decrease of which is also less robust. The response of extreme flows is even more contrasted, with a decrease of low-flow quantiles, whereas high-flow quantiles would not change significantly. In the Beauce region, one of the hotspots for irrigation in Europe, we show that the increase in potential demand for irrigation would have a lesser impact on water resources than the decrease in groundwater recharge directly caused by climate change, which is enough in itself to threaten the reliability of water resources.
Government subsidies for agricultural activities in recent decades have encouraged farmers of Hamadan-Bahar plain to extend the number of wells and irrigated farms, with no consideration of groundwater resource conservation. As a result, the level of the groundwater table has decreased continuously in this area, threatening the life of groundwater aquifer. The objective of the study is to analyze the impacts of irrigation water pricing and agricultural policy scenarios on aquifer conservation by considering the dynamic relations between aquifer groundwater balance and the agriculture sector. For this purpose a combination of simulation and optimization techniques is considered in a dynamic framework. Firstly, dynamic treatments of groundwater and the main factors affecting the balance of studied aquifer are simulated. Then, optimization behaviour of agriculture sector related to farmers' decision-making processes is defined on the time horizon. Thereafter all of the equations are used simultaneously by a non-linear dynamic programming method, which maximize present value of gross margins of agriculture sector subject to groundwater constrains and other input limitations. The analysis of the results indicates that water pricing by itself can considerably reduce the agricultural demand for aquifer groundwater in the Hamadan-Bahar plain.
This paper presents a model developed in the Netherlands for the estimation of damage caused by floods. The model attempts to fill the gap in the international literature about integrated flood damage modelling and develop an integrated framework for the assessment of both direct hazard-induced damages and indirect economic damages such as the interruption of production flows outside the flood affected area, as well as loss of life due to flooding. The scale of damage assessment varies from a specified flood-prone area in a river basin or a coastal region to the country's entire economy. The integrative character of the presented model is featured by the combination of information on land use and economic data, and data on flood characteristics and stage-damage functions, where the geographical dimension is supported by modern GIS to obtain a damage estimate for various damage categories. The usefulness of the model is demonstrated in a case study estimating expected flood damage in the largest flood-prone area in the Netherlands.
Robustness is a key criterion for evaluating alternative decisions under conditions of deep uncertainty. However, no systematic, general approach exists for finding robust strategies using the broad range of models and data often available to decision makers. This study demonstrates robust decision making (RDM), an analytic method that helps design robust strategies through an iterative process that first suggests candidate robust strategies, identifies clusters of future states of the world to which they are vulnerable, and then evaluates the trade-offs in hedging against these vulnerabilities. This approach can help decision makers design robust strategies while also systematically generating clusters of key futures interpretable as narrative scenarios. Our study demonstrates the approach by identifying robust, adaptive, near-term pollution-control strategies to help ensure economic growth and environmental quality throughout the 21st century.
The main objective of this paper is to study the impacts of climate change on the hydrological cycle of the main French river basins, including the different uncertainties at stake. In particular, the relative importance of modeling uncertainty versus that of downscaling uncertainty is investigated. An ensemble of climate scenarios are statistically downscaled in order to force a hydrometeorological model over France. Then, the main changes in different variables of the hydrological cycle are studied. Despite large uncertainties linked to climate models, some robust signals already appear in the middle of the 21st century. In particular, a decrease in mean discharges in summer and fall, a decrease in soil moisture, and a decrease in snow cover, especially pronounced at the low and intermediate altitudes, are simulated. The low flows become more frequent but generally weak, and uncertain changes in the intensity of high flows are simulated. To evaluate downscaling uncertainties and assess the robustness of the results obtained with the statistical downscaling method, two other downscaling approaches are used. The first one is a dynamical downscaling methodology based on a variable resolution atmospheric model, with a quantile-quantile bias correction of the model variables. The second approach is based on the so-called anomaly method, that simply consists of perturbing present climate observations by the climatological change simulated by global climate models. After hydrological modeling, some discrepancies exist among the results from the different downscaling methods. However they remain limited and to a large extent smaller than climate model uncertainties, which raises important methodological considerations.
Policy for water resources impacts not only hydrological processes, but the closely intertwined economic and social processes dependent on them. Understanding these process interactions across domains is an important step in establishing effective and sustainable policy. Multidisciplinary integrated models can provide insight to inform this understanding, though the extent of software development necessary is often prohibitive, particularly for small teams of researchers. Thus there is a need for practical methods for building interdisciplinary integrated models that do not incur a substantial development effort. In this work we adopt the strategy of linking individual domain models together to build a multidisciplinary integrated model. The software development effort is minimized through the reuse of existing models and existing model-linking tools without requiring any changes to the model source codes, and linking these components through the use of the Open Modeling Interface (OpenMI). This was found to be an effective approach to building an agricultural-groundwater-economic integrated model for studying the effects of water policy in irrigated agricultural systems. The construction of the integrated model provided a means to evaluate the impacts of two alternative water-use policies aimed at reducing irrigated water use to sustainable levels in the semi-arid grasslands overlying the Ogallala Aquifer of the Central US. The results show how both the economic impact in terms of yield and revenue and the environmental impact in terms of groundwater level vary spatially throughout the study region for each policy. Accessible integration strategies are necessary if the practice of interdisciplinary integrated simulation is to become widely adopted.
This paper uses simple hydro-economic optimization to investigate a wide range of regional water system management options for northern Baja California, Mexico. Hydro-economic optimization models, even with parsimonious model formulations, enable investigation of promising water management portfolios for supplying water to agricultural, environmental and urban users. CALVIN, a generalized hydro-economic model, is used in a case study of Baja California. This drought-prone region faces significant challenges to supply water to agriculture and its fast growing border cities. Water management portfolios include water markets, wastewater reuse, seawater desalination and infrastructure expansions. Water markets provide the flexibility to meet future urban demands; however conveyance capacity limits their use. Wastewater reuse and conveyance expansions are economically promising. At current costs desalination is currently uneconomical for Baja California compared to other alternatives. Even simple hydro-economic models suggest ways to increase efficiency of water management in water scarce areas, and provide an economic basis for evaluating long-term water management solutions.
Theory suggests that the development of common property increases national welfare, and consistent with this thinking Australia's Murray–Darling Basin (MDB) Plan uses a common property approach to recover environmental water rights in the national interest. Two water recovery instruments are used: purchasing water rights (buyback) from farmers, and saving water by subsidising irrigator adoption of technically efficient technology. A moratorium on buyback has focused environmental recovery on subsidised technically efficient technology adoption. Economists argue that national welfare is maximised via buyback and highlight the limitations of efficiency savings to recover sufficient environmental water. A risk is that water recovery targets may be reduced in future, limiting welfare gains from water reform. This article evaluates possible welfare trade-offs surrounding environmental water recovery outcomes where arbitrary limits on buyback are imposed. Results suggest that, on average, strategies which attempt to obtain >1500 gigalitres (GL) of water from on-farm efficiency investments will only provide sufficient resources to meet environmental objectives in very wet states of nature. We conclude that reliance on technically efficient irrigation infrastructure is less economically efficient relative to water buyback. Importantly, the transformation of MDB irrigation will significantly constrain irrigators' future capacity to adapt to climate change.
The realization of buyback welfare enhancing opportunities is conditioned to the ability of government agencies to place bids consistent with the shadow price of irrigators. However, methods used to inform buyback programmes to date either rely on ex-post trading data that is not readily available in most regions worldwide; or compensate projected foregone income, and thus ignore the effects that buyback may have on other relevant attributes determining utility. This paper uses revealed preference methods to elicit the parameters of a multi-attribute objective function that mimics the observed behavior of irrigators in the overexploited Segura River Basin in SE Spain. Objective functions are used in a series of simulations in which water allocation is progressively constrained to ex-ante reveal the shadow price of water using two alternative compensation measures: i) the foregone income, a proxy of the shadow price typically used in the literature; and ii) the compensating variation that addresses foregone utility. Results show a relevant gap between the two methods For example, restoring the balance in the basin through purchase tenders would demand an investment of million 2400+ EUR (9.6+ EUR m⁻³) attending to the foregone income method, and million 950+ EUR (3.8+ EUR m⁻³) (−60.3%) with the foregone utility method.
La nappe de la Beauce est l'un des rares aquifères faisant l'objet en France d'une gestion volumétrique négociée entre la profession agricole et l'Administration. Depuis 1999, des volumes de référence sont alloués à chacune des quelque 3 600 exploitations agricoles, réparties sur six départements, qui prélèvent de l'eau à usage agricole dans l'aquifère. Chaque année, les volumes prélevables sont définis par l'application aux volumes de référence d'un coefficient de réduction en fonction du niveau piézométrique moyen. Depuis 2003, la décroissance du niveau de la nappe a conduit à une diminution importante des volumes prélevables et présage d'un avenir difficile. Cet article présente une démarche développée avec les acteurs pour analyser les adaptations et leurs conséquences agronomiques et économiques dans des contextes, pour l'heure hypothétiques, de forte décroissance des volumes prélevables.
Efficient water management in agriculture is becoming critical due to increasing environmental constraints and global food
and bio-energy demands. Farmers may respond to increased water scarcity along three main adjustment margins: a move towards
rain-fed agriculture (super-extensive margin) or towards less water-intensive crops (extensive margin), and a reduction in
water intensity for irrigated crops (intensive margin). Using a positive mathematical programming model of regional supply
calibrated to economic and agronomic information, we decompose the total effect of reduced water availability on these adjustment
margins in Beauce, a productive cereal region that relies on a groundwater resource to meet its irrigation needs. For realistic
water scarcity scenarios, 57 per cent of the total response is attributable to super-extensive margin adjustments. The extensive
margin represents 28 per cent of the total response, while the intensive margin accounts for 15 per cent. Crop-level analysis
reveals more subtle adaptation patterns.
Most of the world's water entitlement and allocation regimes evolved during periods of abundance and, hence, are not well suited to the management of water scarcity. Development of the institutional arrangements necessary to manage changing demands and supplies is in its infancy.
Design criteria for the development of a set of institutional arrangements for the robust management of scarce water resources is offered and then used to develop a generic framework for the allocation and use of water. Variations to account for differences in ground, regulated and unregulated water resources are offered. The question of how best to sequence reform of existing water entitlement and allocation regimes is also addressed.
The result is a recommendation for the use of water sharing plans to determine how much water may be used at any point in time and an unbundled suite of arrangements that enable efficient but separated management of long term and short term considerations and, also, the control of externalities.
System-wide adjustment is facilitated through the periodic revision of water sharing plans. Individual adjustment to changing circumstances is facilitated through trade in entitlements and allocations.
Before the introduction of institutional arrangements that encourage adjustment through trade it is recommended that the abstraction regime used be converted into one that accounts for return flows and allocates water according to shareholder entitlement. Seniority, beneficial-use criteria and opportunities to third parties to prevent adjustment according to pre-specified rules should be repealed. Well-designed regimes can be extended to include dam-capacity shares and allow the use of market-based instruments in delivery of water-quality objectives. Pooling can be used to lower the costs of risk management.
This study explores groundwater management policies and the effect of modeling assumptions on the projected performance of those policies. The study compares an optimal economic allocation for groundwater use subject to streamflow constraints, achieved by a central planner with perfect foresight, with a uniform tax on groundwater use and a uniform quota on groundwater use. The policies are compared with two modeling approaches, the Optimal Control Model (OCM) and the Multi-Agent System Simulation (MASS). The economic decision models are coupled with a physically based representation of the aquifer using a calibrated MODFLOW groundwater model. The results indicate that uniformly applied policies perform poorly when simulated with more realistic, heterogeneous, myopic, and self-interested agents. In particular, the effects of the physical heterogeneity of the basin and the agents undercut the perceived benefits of policy instruments assessed with simple, single-cell groundwater modeling. This study demonstrates the results of coupling realistic hydrogeology and human behavior models to assess groundwater management policies. The Republican River Basin, which overlies a portion of the Ogallala aquifer in the High Plains of the United States, is used as a case study for this analysis.
In arid countries worldwide, social conflicts between irrigation-based human development and the conservation of aquatic ecosystems are widespread and attract many public debates. This research focuses on the analysis of water and agricultural policies aimed at conserving groundwater resources and maintaining rural livelihoods in a basin in Spain's central arid region. Intensive groundwater mining for irrigation has caused overexploitation of the basin's large aquifer, the degradation of reputed wetlands and has given rise to notable social conflicts over the years. With the aim of tackling the multifaceted socio-ecological interactions of complex water systems, the methodology used in this study consists in a novel integration into a common platform of an economic optimization model and a hydrology model WEAP (Water Evaluation And Planning system). This robust tool is used to analyze the spatial and temporal effects of different water and agricultural policies under different climate scenarios. It permits the prediction of different climate and policy outcomes across farm types (water stress impacts and adaptation), at basin's level (aquifer recovery), and along the policies’ implementation horizon (short and long run). Results show that the region's current quota-based water policies may contribute to reduce water consumption in the farms but will not be able to recover the aquifer and will inflict income losses to the rural communities. This situation would worsen in case of drought. Economies of scale and technology are evidenced as larger farms with cropping diversification and those equipped with modern irrigation will better adapt to water stress conditions. However, the long-term sustainability of the aquifer and the maintenance of rural livelihoods will be attained only if additional policy measures are put in place such as the control of illegal abstractions and the establishing of a water bank. Within the policy domain, the research contributes to the new sustainable development strategy of the EU by concluding that, in water-scarce regions, effective integration of water and agricultural policies is essential for achieving the water protection objectives of the EU policies. Therefore, the design and enforcement of well-balanced region-specific polices is a major task faced by policy makers for achieving successful water management that will ensure nature protection and human development at tolerable social costs. From a methodological perspective, this research initiative contributes to better address hydrological questions as well as economic and social issues in complex water and human systems. Its integrated vision provides a valuable illustration to inform water policy and management decisions within contexts of water-related conflicts worldwide.
Risk preferences broadly affect many economic decisions when markets are incomplete. Common representations of risk preferences are constant absolute, relative, and partial relative risk aversion. Each of these preference classes has distinct impacts on choice. An econometric test for distinguishing the class of preferences is proposed and implemented for potato supply response in Idaho. The data reject constant absolute and partial relative risk aversion and are congruent with constant relative risk aversion.
Increased irrigation has been identified as an important potential adaptation to meet growing world food demand. Yet many of the world's major irrigation regions are in arid and semi-arid regions that face climate change projections of hotter and drier weather. A growing body of analysis assesses irrigated agriculture impacts of climate change in such regions. Most published literature focuses on reductions in the mean-levels of freshwater supplies: less information is available on the potential impacts from changes in the reliability and quality of those diminishing water supplies. This article investigates the combined impacts on irrigated agricultural food supply from reduced, more variable and more saline water supply for a representative semi-arid irrigation region. Results indicate that understanding the potential impacts of climate change on agricultural production requires an understanding of not only how production may adapt to changes in mean water supplies, but also how it may respond to changes in water supply variability and salinity. We illustrate, using an Australian, Murray Darling Basin semi-arid region example, that ignoring these combined water-related climate effects lead to results that overlook thresholds where the structure of production and cost incurred fundamentally change above certain levels of variability and salinity. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.
We investigate the behavior of farmers who share an underground aquifer. In the case where seepage may occur the resource is nonexclusive, giving rise to a spatial externality whereby pumping by one user affects others nearby. Theoretically, these externalities are potentially important causes of welfare loss. Using a unique spatial data set of groundwater users in western Kansas, we are able to empirically measure the physical and behavioral effects of groundwater pumping by neighbors. To address the simultaneity of neighbors' pumping, we use the neighbors' permitted water allocation as an instrument for their pumping. We estimate that 2.5% of the total groundwater extracted each year in western Kansas is over-extraction due to the effects of spatial externalities. Individuals who own multiple wells internalize their own externality by trading off pumping at one well for pumping at another.
This article provides a methodology to exactly calibrate land-constrained programming models of agricultural supply against supply elasticities using generalized constant-elasticity-of-substitution, crop-specific production functions. We formally derive the necessary and sufficient conditions under which the model can replicate a reference allocation while displaying crop supply responses consistent with exogenous information on supply elasticities. When it exists, the solution to the exact calibration problem is unique. Subject to a caveat, the proposed specification is shown to be more flexible with respect to calibration than the quadratic specification that has been used extensively in policy models based on positive mathematical programming. Copyright 2011, Oxford University Press.
This paper is concerned with optimal allocation over time of a single resource which is either fixed in supply or only partially renewable at a point in time. Some resources which fall in this category are mineral deposits, ground water, petroleum, wildlife, and fish. A functional equation is obtained from a dynamic programming formulation of the problem. This functional equation is used to derive approximate decision rules for resource use as a function of current supply. The results are applied to ground water storage control and tested empirically by comparison with a decision rule obtained by detailed numerical methods.
Estimating the impacts of climate change on groundwater represents one of the most difficult challenges faced by water resources specialists. One difficulty is that simplifying the representation of the hydrological system often leads to discrepancies in projections. This study provides an improved methodology for the estimation of the impacts of climate change on groundwater reserves, where a physically-based surface–subsurface flow model is combined with advanced climate change scenarios for the Geer basin (465 km2), Belgium. Coupled surface–subsurface flow is simulated with the finite element model HydroGeoSphere. The simultaneous solution of surface and subsurface flow equations in HydroGeoSphere, as well as the internal calculation of the actual evapotranspiration as a function of the soil moisture at each node of the defined evaporative zone, improve the representation of interdependent processes like recharge, which is crucial in the context of climate change. More simple models or externally coupled models do not provide the same level of realism. Fully-integrated surface–subsurface flow models have recently gained attention, but have not been used in the context of climate change impact studies. Climate change simulations were obtained from six regional climate model (RCM) scenarios assuming the SRES A2 emission (medium–high) scenario. These RCM scenarios were downscaled using a quantile mapping bias-correction technique that, rather than applying a correction only to the mean, forces the probability distributions of the control simulations of daily temperature and precipitation to match the observed distributions. The same corrections are then applied to RCM scenarios for the future. Climate change scenarios predict hotter and drier summer and warmer and wetter winters. The combined use of an integrated surface–subsurface modelling approach, a spatial representation of the evapotranspiration processes and sophisticated climate change scenarios improves the model realism and projections of climate change impacts on groundwater reserves. For the climatic scenarios considered, the integrated flow simulations show that significant decreases are expected in the groundwater levels (up to 8 m) and in the surface water flow rates (between 9% and 33%) by 2080.
In this paper socially optimal and private extraction of a common property aquifer are compared. Open-loop equilibrium and feedback equilibrium in linear strategies have been computed to characterize private extraction. The use of these two equilibrium concepts allows us to distinguish between cost and strategic externalities as long as the open-loop solution captures only the cost externality, and the feedback solution captures both. The results show that strategic behaviour increases the overexploitation of the aquifer compared to the open-loop solution. However, if the groundwater storage capacity is large, the difference between the socially optimal and private extraction, the latter characterized by a feedback equilibrium, is negligible.
Future water management will shift from building new water supply systems to better operating existing ones. The variation of water values in time and space will increasingly motivate efforts to address water scarcity and reduce water conflicts. Hydro-economic models represent spatially distributed water resource systems, infrastructure, management options and economic values in an integrated manner. In these tools water allocations and management are either driven by the economic value of water or economically evaluated to provide policy insights and reveal opportunities for better management. A central concept is that water demands are not fixed requirements but rather functions where quantities of water use at different times have varying total and marginal economic values. This paper reviews techniques to characterize the economic value of water use and include such values in mathematical models. We identify the key steps in model design and diverse problems, formulations, levels of integration, spatial and temporal scales, and solution techniques addressed and used by over 80 hydro-economic modeling efforts dating back 45-years from 23 countries. We list current limitations of the approach, suggest directions for future work, and recommend ways to improve policy relevance.
Many decisions concerning long-lived investments already need to take into account climate change. But doing so is not easy for at least two reasons. First, due to the rate of climate change, new infrastructure will have to be able to cope with a large range of changing climate conditions, which will make design more difficult and construction more expensive. Second, uncertainty in future climate makes it impossible to directly use the output of a single climate model as an input for infrastructure design, and there are good reasons to think that the needed climate information will not be available soon. Instead of optimizing based on the climate conditions projected by models, therefore, future infrastructure should be made more robust to possible changes in climate conditions. This aim implies that users of climate information must also change their practices and decision-making frameworks, for instance by adapting the uncertainty-management methods they currently apply to exchange rates or R&D outcomes. Five methods are examined: (i) selecting “no-regret” strategies that yield benefits even in absence of climate change; (ii) favouring reversible and flexible options; (iii) buying “safety margins” in new investments; (iv) promoting soft adaptation strategies, including long-term prospective; and (v) reducing decision time horizons. Moreover, it is essential to consider both negative and positive side-effects and externalities of adaptation measures. Adaptation–mitigation interactions also call for integrated design and assessment of adaptation and mitigation policies, which are often developed by distinct communities.
Min–max and min–max regret criteria are commonly used to define robust solutions. After motivating the use of these criteria, we present general results. Then, we survey complexity results for the min–max and min–max regret versions of some combinatorial optimization problems: shortest path, spanning tree, assignment, min cut, min s–t cut, knapsack. Since most of these problems are NP-hard, we also investigate the approximability of these problems. Furthermore, we present algorithms to solve these problems to optimality.
When entitlements to access water in fully allocated river and aquifers are specified in a manner that is inconsistent with the ways that water arrives, flows across and flows through land, inefficient investment and water use is the result. Using Australia's Murray Darling Basin as an example, this paper attempts to reveal the adverse economic and water management consequences of entitlement and water sharing regime misspecification in regimes that allow water trading. Markets trade water products as specified. When entitlements and the water sharing system are not designed in a way that has hydrological integrity, the market trades the water management regime into trouble. Options for specification of entitlement and allocation regimes in ways that have hydrological integrity are presented. It is reasoned, that if entitlement and allocation regime are set up in ways that have hydrological integrity, the result should be a regime that can autonomously adjust to climatic shifts, changes in prices and changes in technology without compromising environmental objectives. Copyright 2009 The Authors. Journal compilation 2009 Australian Agricultural and Resource Economics Society Inc. and Blackwell Publishing Asia Pty Ltd.
A method for calibrating agricultural production models is presented. The data requirements are those for a linear programming model with the addition of elasticities of substitution. Using these data, production models with a CES production function can be simply and automatically calibrated using small computers. The resulting models are shown to satisfy the standard microeconomic conditions. When used for analysis of policy changes, the CES models are able to respond smoothly to changes in prices or constraints. Prior estimates of elasticities of substitution, supply or demand can be incorporated in the models.
Many commentators have suggested the need for new decision analysis approaches to better manage systems with deeply uncertain, poorly characterized risks. Most notably, policy challenges such as abrupt climate change involve potential nonlinear or threshold responses where both the triggering level and subsequent system response are poorly understood. This study uses a simple computer simulation model to compare several alternative frameworks for decision making under uncertainty -- optimal expected utility, the precautionary principle, and three different approaches to robust decision making -- for addressing the challenge of adding pollution to a lake without triggering unwanted and potentially irreversible eutrophication. The three robust decision approaches -- trading some optimal performance for less sensitivity to assumptions, satisficing over a wide range of futures, and keeping options open -- are found to identify similar strategies as the most robust choice. This study also suggests that these robust decision approaches offer a quantitative, decision analytic framework that captures the spirit of the precautionary principle while addressing some of its shortcomings. Finally, this study finds that robust strategies may be preferable to optimum strategies when the uncertainty is sufficiently deep and the set of alternative policy options is sufficiently rich.
The issue of groundwater management remains a practical concern in many regions throughout the world, while water managers continue to grapple with the question of how to manage this resource. In this article, we attempt to bring the most advanced and appropriate tools to bear on the issue of resource allocation involving groundwater. Our objective is to demonstrate the state of the art in the literature on ways to think about this complex resource and to deal with the important economic issues emanating from its complexity. We present the conceptual framework within which economists examine the elements interacting in the management of groundwater resources, indicate why the role of the market is limited with respect to the price of this very complex resource, and point to the mechanisms that can pull competitive groundwater price and quality-graded quantity of groundwater in line with their equilibrium levels. In particular, we critically review economic models of groundwater use, examine the potential for groundwater management, discuss the difficulties encountered in the estimation of the relevant control variables of such models, and identify the advantages and limitations of the instruments devised for the efficient use (allocation) of this resource. Finally, we argue that devised regulatory schemes usually ignore the information and knowledge needed for their implementation, and we suggest a core of conditions necessary for successful groundwater management reforms. Copyright Blackwell Publishers Ltd, 2004.
We present the results of a framed field experiment with Ethiopian farmers that use the mountain rain forest as a common pool resource. Harvesting honey causes damage to the forest, and open access leads to over-harvesting. We test different mechanisms for mitigating excessive harvesting: a collective tax with low and high tax rates, and a tax/subsidy system. We find that the high-tax scheme works best in inducing the desired level of harvesting, while the tax-subsidy scheme may trigger tacit collusion. Via a panel data analysis we further investigate which variables influence the subjects' decisions during the treatments.
Integrated hydro-economic models aim to capture the complexity of interactions between water and the economy. Three main approaches are distinguished: modular, holistic and computable general equilibrium models. The latter top-down models counterbalance the traditional emphasis on bottom-up water engineering approaches. Key issues and future research directions in integrated hydro-economic modelling are discussed and illustrated through a variety of case study applications worldwide. Although the interaction works both ways, feedback effects of water changes on the economy and changes in the economy on the water system are often missing in practice. The link between water and ecology is another important future research direction.
In this paper we analyse the optimal management of a renewable resource (groundwater) with stock-dependent extraction cost and a backstop substitute, facing two-sector linear demands. Application to the Kiti region in Cyprus demonstrates the model's performance and is used to test for the difference between optimal and myopic behaviour. It is found that the presence of a backstop resource diminishes the importance of optimal dynamic behaviour, whereas in the absence of backstop the optimal control solution yields a value for social welfare significantly larger than the myopic policy. Copyright Australian Agricultural and Resource Economics Society Inc. and Blackwell Publishing Ltd 2006.
- Eurostat
Eurostat, Crop Production Statistics, (2012).
A retrospective look at the evolution of irrigation governance in the Beauce area
- O Petit
O. Petit, A retrospective look at the evolution of irrigation governance in the Beauce area (1993-2008), Secheresse (Montrouge) 20 (2009) 262-270.
La gestion volumétrique de l'eau en Beauce : impact sur les exploitations agricoles
- S Morardet
- S Hanot
S. Morardet, S. Hanot, "La gestion volumétrique de l'eau en Beauce : impact sur les exploitations agricoles." Working paper, Cemagref -Agence de l'Eau Loire-Bretagne, December, 2000.
Contribution des principaux aquifères au fonctionnement hydrologique de la Loire en région Centre -caractérisation et bilans par bassins versants souterrains, BRGM/RP-60381-FR (2012) 131 106 ill
- S Schomburgk
- A Brugeron
- A Winckel
- N Ruppert
- D Salquebre
- J Martin
S. Schomburgk, A. Brugeron, A. Winckel, N. Ruppert, D. Salquebre, J. Martin, Contribution des principaux aquifères au fonctionnement hydrologique de la Loire
en région Centre -caractérisation et bilans par bassins versants souterrains, BRGM/RP-60381-FR (2012) 131 106 ill., 11 ann.
Ministère de l'agriculture et de l'agroalimentaire
Ministère de l'agriculture et de l'agroalimentaire, Statistique Agricole Annuelle -AGRESTE, (2012).
Etude sur les conséquences de l'économie agricole régionale des contraintes en matière de gestion de l'eau : pistes de réflexion pour une priorisation des prélèvements
- L Brunel
- S Bouarfa
- P Ruelle
L. Brunel, S. Bouarfa, P. Ruelle, "Etude sur les conséquences de l'économie agricole régionale des contraintes en matière de gestion de l'eau : pistes de réflexion
pour une priorisation des prélèvements." Working paper, Cemagref and Ministère de l'agriculture et de la pêche, Décembre, (2007).
A retrospective look at the evolution of irrigation governance in the Beauce area (1993-2008)
- Petit
Contribution des principaux aquifères au fonctionnement hydrologique de la Loire en région Centre - caractérisation et bilans par bassins versants souterrains
- Schomburgk