How to link agricultural productivity, water availability and water demand in a risk context: a model for managing hydrological risks

Abstract

The importance of water scarcity in irrigated agriculture in Spain provides the rationale for this paper, which analyses and evaluates the risk of water shortage on the economic result of this kind of agriculture. The main objective is to monitor this risk on a real-time basis. For this aim, we first estimated a number of regression models that explain irrigated agricultural productivity based on crop price indices, a time trend and water availability. These models, which correct for auto-correlation, yield good explanatory power. Second we carried out ex ante simulations of agricultural productivity using fitted distribution functions of water balance. The risk model framework provides the basis for a real time drought management system through a variety of distribution functions of expected economic results, which can be revised on a monthly basis before the beginning of the irrigation season. The results of the simulation show how this kind of risk model can be used to anticipate the effects of droughts and complement the hydrological models used to manage water storage in years of scarcity. Different risk profiles are identified. For example, in Genil-Cabra we found that the resilience of the system after a drought period is very high, whereas in La Plana de Castellón the risk of irrigation area abandonment is increasing year by year. In Genil-Cabra the estimated losses were 60 million euros in 2007. The models were applied to some of the most agriculturally relevant irrigation districts in Spain.Additional key words: drought management; irrigation; stochastic models; water productivity; water supply instability. ResumenCómo vincular la productividad agrícola, la disponibilidad de agua y demanda de agua en un contexto de riesgo: un modelo para gestionar los riesgos hidrológicos La importancia de la sequía sobre la agricultura de regadío es el fundamento de este artículo que analiza y evalúa el riesgo de escasez de agua sobre el resultado económico de este tipo de agricultura. El objetivo es controlar en tiempo real dicho riesgo. Se estiman diversos modelos de regresión que explican la productividad del regadío a través de un índice de precios ponderado para los principales cultivos, la tendencia y la disponibilidad de agua. Estos modelos, que se corrigen por auto-correlación, muestran una buena capacidad explicativa. En segundo lugar se llevan a cabo simulaciones ex-ante de la productividad del regadío empleando funciones ajustadas del balance de agua. Este marco metodológico proporciona la base para un sistema de gestión del riesgo de sequía en tiempo real a través de funciones de distribución de los resultados económicos esperados, que pueden ser revisadas de manera mensual antes del inicio de la campaña de riegos. Los resultados de la simulación demuestran que se pueden anticipar los efectos de las sequías, y por tanto, servir a los gestores del agua como complemento de los modelos hidrológicos para gestionar las reservas de agua en los años de escasez. Se identifican diferentes perfiles de riesgo...

Assessing the effectiveness of Multi‐Sector Partnerships to manage droughts: The case of the Jucar river basin

“…Crop price is introduced as an independent variable in order to separate the effect of price changes (volatility) from the consequences of reduced water delivered for irrigation. The econometric model is set as [based on Gil‐Sevilla et al, ]: where “ W ” represents the surface water deliveries, “ G ” represents groundwater deliveries, and “Ip” is the crop price index.…”

“…Crop price is introduced as an independent variable in order to separate the effect of price changes (volatility) from the consequences of reduced water delivered for irrigation. The econometric model is set as [based on Gil-Sevilla et al, 2010]:…”

Risk in agriculture: An overview of the theoretical insights and recent development trends during last decade - A review

“…In the last publication, the authors (Maestro et al 2016) refer to the Spanish Crop Insurance System framework and propose an insurance instrument to handle the risk of water scarcity. Also, this author with co-authors (Gil-Sevilla et al 2010) introduced a model for managing hydrological risks. This model can be used in agriculture to manage water storage in years of scarcity.…”

Direct and indirect economic impacts of drought in the agri-food sector in the Ebro River basin (Spain)

“…The direct attribution model has been adapted from previous models Gil-Sevilla et al, 2010;Gil et al, 2011). In the methodology proposed in this paper, the value of production is the variable to be explained when direct damages are considered.…”

“…The methodology proposed here follows the general econometric models developed by Garrido et al (2010), Gil-Sevilla et al (2010) and Gil et al (2011) to measure drought impacts using impact attribution models. This work focuses geographically on the Ebro River basin (in northeastern Spain) and considers 15 yr of data (1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009).…”