Evolución de la productividad del agua en la Cuenca del Guadalquivir 1989-2005

Abstract

RESUMEN:Para entender el desarrollo de la agricultura de riego es necesario estudiar la evolución de la productividad del agua en los cultivos de regadío. Este trabajo analiza la evolución de este indicador en los años 1989 y 2005 en la Cuenca del Guadalquivir. Para ello, se han utilizado datos estadísticos que, primero, han sido tratados a nivel comarcal y de cultivo y, posteriormente, se han agregado hasta obtener un valor global para toda la cuenca. Del conjunto de los resultados se deduce un valor de la productividad aparente del agua de aproximadamente un 0,5 €/m 3 para el año 2005 y un incremento de un 327% respecto al año 1989.PALABRAS CLAVE: Regadío, productividad, agua, eficiencia, escasez.Clasificación JEL: O13, Q25. Evolution of water productivity in the Guadalquivir basin 1989-2005SUMMARY: In order to understand the development of irrigated agriculture, it is necessary to study the evolution of irrigated crop water productivity. This research analyzes the evolution of this indicator for the Guadalquivir basin between 1989 and 2005. Statistical data has firstly been treated at a regional and cultivation level and, subsequently, they have been aggregated to obtain a global value for the whole basin. Results indicate that the irrigated crop water productivity is 0.5 €/m 3 for 2005 representing a 327% increase with respect to the 1989 value.

Agricultural Irrigation Water Use in a Closed Basin and the Impacts on Water Productivity: The Case of the Guadalquivir River Basin (Southern Spain)

“…Therefore, mean irrigation water productivity may be estimated as the difference between the estimated economic productivity (in terms of GVA generated per hectare) of irrigated agriculture and that of rain-fed farming. As argued by Carrasco et al [22], it seems clear that this assumption represents an important limitation, as resulting estimates would be valid only if the sole difference between rain-fed and irrigated agriculture were the amount of water used. In practice, however, it is clear that other differentiating factors, such as the use intensity of physical and human capital involved in crop cultivation, play a relevant role in explaining productivity differences.…”

“…Table 4 shows the yields obtained by rain-fed and irrigated agriculture in terms of the gross value added (GVA) in the Guadalquivir RB. Data for 1989 and 2005 are obtained from the estimates made by Carrasco et al [22], and these are supplemented with our own estimates for 2012. GVA measures have been estimated based on data for prices, crop yields, subsidies and direct costs, all of which have been sourced from the Agricultural and Fisheries Statistics of Andalusia, the Prices and Markets Observatory of Andalusia's Council of Agriculture and Fisheries (CAP), as well as the Survey of Crops and Agricultural Incomes from the Spanish Ministry of Agriculture, Food and Environment (MAGRAMA).…”

“…Following Carrasco et al [22], we assume that the increase in the economic productivity of irrigated agriculture due to improvements in labor and capital factors (e.g., improved seeds, machinery, etc.) is incorporated in the productivity of land and estimated by the increase over rain-fed farming productivity.…”

Distribution of dissolved organic matter in estuaries of the southern Iberian Atlantic Basin: Sources, behavior and export to the coastal zone

“…However, this river is subjected to elevated anthropogenic pressure due to densely populated areas on its margins (4.2 million people), as well as the development of agriculture and aquaculture industries, and a high demand of freshwater for irrigation. Irrigated crops occupy ~ 8100 Km 2 (Carrasco et al, 2010) that used ~ 85 % of the withdrawal water from this river (www.chguadalquivir.es). Guadiana is a rock-bound estuary, which consists of a single narrow channel (50 -700 m wide) (Morales and Garel, 2019).…”

Integration of hydrological and economic approaches to water and land management in Mediterranean climates: an initial case study in agriculture

“…Applied Water" and analyzed productivity in terms of water distributed to the crop. Lorite et al (2004a,b and2007), Gil et al (2009), Lorite and Arriaza (2009) and Carrasco et al (2010) described the calculation of irrigation water productivity (in kg m -3 ) of irrigation applied. These authors also treated the increase in the value of output due to irrigation as the difference between the irrigated crop yield minus the same crop yield on unirrigated land at market prices, following a procedure similar to that defined in Rodríguez Casado et al (2008) and Novo et al (2009).…”