Water saving and irrigation modernization

La modernización de regadíos está suponiendo una profunda transformación de la estructura productiva del sector agrario español. Sus implicaciones superan el ámbito de las infraestructuras hidráulicas, al implicar la conversión de una agricultura protegida en una agricultura competitiva. Una de las consecuencias de este proceso es el cambio en el modo de aprovechar los recursos hídricos en el sector agrario. Un cambio que a su vez va a tener repercusiones en la hidrología de las cuencas. En este artículo se analizan las consecuencias de la modernización sobre el consumo de agua aplicando la metodología de la contabilidad del agua. Para ello se han considerado los resultados obtenidos en distintos proyectos de investigación desarrollados en la cuenca del Ebro. La sustitución de sistemas de riego por superficie por sistemas de riego presurizados supondrá un aumento del consumo de agua. No obstante, la magnitud de este impacto estará supeditada a la mejora de la gestión del agua y la evolución de los precios de las materias primas agrarias y de la energíaIrrigation modernization is leading to a deep transformation of the productive structure of the Spanish agriculture. Their implications overcome the scope of the hydraulic infrastructures implying the transformation from protective to competitive agriculture. One consequence of this process is the change in the way that agriculture uses the water resources. This change in turn has implications for the hydrology of the river basins. This paper analyses the consequences of the irrigation modernization in water consumption applying the concepts of the water accounting. The results obtained in several research projects performed in the Ebro River Basin have been used for this purpose. The change of surface irrigation systems by pressurized systems will imply an increase of water consumption. Nevertheless, the magnitude of this impact will be subordinate to the improvement of water management and the variations of the prices in agricultural commodities and energ

Field test of an automatic controller for solid-set sprinkler irrigation

The application of new technologies to the control and automation of irrigation processes is becoming very important, and the automatic generation and execution of irrigation schedules is receiving growing attention. In this paper, a prototype automatic irrigation controller for solid-set systems is presented. The device is composed by software and hardware developments. The software was named Ador-Control and it integrates five modules: the first four modules simulate drop trajectories, water distribution, crop growth and yield, and the last module ensures bidirectional communication between software and hardware. Decision variables based on soil, crop, and irrigation performance indexes were used to make real-time irrigation decisions. A randomized experimental design was designed to validate the automatic controller over a corn crop during two seasons. Three treatments were analyzed: T0) manual programmer or advanced farmer; T1) automatic scheduling controlled by indexes based on soil simulated water content and irrigation performance; and T2) advanced automatic scheduling controlled by simulated thresholds of crop and irrigation indexes. Experimental results in 2009 and 2010 indicated that automatic irrigation treatments resulted in similar maize yield but using less water than manual irrigation (10 % between T0 and T1, and 18 % between T0 and T2).Peer ReviewedPublishe

Automatic programmers for solid set sprinkler irrigation systems

6 Pags., 1 Tabl., 2 Figs.Introduction: The application of new technologies to the control and automation of irrigation processes is becoming very important in the last decade. Although automation of irrigation execution (irrigation programmers) is now widespread the automatic generation and execution of irrigation schedules is receiving growing attention due to the possibilities offered by the telemetry / remote control systems currently being installed in collective pressurized networks. In this paper, a prototype autonomous irrigation controller for solid set systems is presented. Material and Methods: The autonomous irrigation controller for solid set sprinkler irrigation systems is composed by software and hardware. The software simulates drop trajectories emitted by each sprinkler (Playán et al., 2006), water distribution in the soil and crop growth and yield (Dechmi et al., 2004, Zapata et al., 2009). Although the model simulates sprinkler water application, the control unit was the irrigated block of the solid set irrigated field. Variability inside an irrigated block was represented by decision variables (irrigation, soil and crop performance indexes) that can control the irrigation timing of the different blocks of the farm. The hardware was a research prototype translating the irrigation schedules into electrical orders to open or close solenoid valves and collecting and transmitting local sensor readings to the software. A field experiment was designed to test and validate the automatic programmer over a corn crop during two irrigation seasons (2009 and 2010). A randomized experimental design with four replicates was used to analyze three treatments: T0) a manual programmer acting as an advanced farmer; T1) automatic scheduling controlled by the estimated water content in the soil and simulated irrigation performance; and T2) advanced automatic scheduling controlled by crop and irrigation simulations. Results/Conclusions: Experimental results in 2009 and 2010 indicated that T0 was the treatment receiving most water, followed by T1 and T2. Yield parameters did not show significant differences between treatments. Automatic irrigation scheduling resulted in similar maize yield to manual irrigation. Differences were relevant in applied water (9% between T0 and T1, and 15% between T0 and T2).This research was funded by the MCINN of the Government of Spain through grants AGL2007-66716-C03-01/02 and AGL2010-21681-C03-01.Peer reviewe

Developing Automatic Controllers for sprinkler irrigation systems

1 Pag.Prospects for the development of such systems in collective sprinkler irrigation systems are analyzed in this presentation. Additionally, experimental results are presented on the application of these concepts to a hydrant irrigating a solid-set irrigated maize field.Peer reviewe

Solid-Set Sprinkler Irrigation Controllers Driven by Simulation Models: Opportunities and Bottlenecks

Farmers continue to show great differences in irrigation water use, even for a given location and crop. Irrigation advisory services have narrowed the gap between scientific knowledge and on-farm scheduling, but their success has been limited. The performance of sprinkler irrigation is greatly affected by factors such as wind speed, whose short-time variability requires tactical adjustments of the irrigation schedule. Mounting energy costs often require the consideration of interday and intraday tariff evolution. Opportunities have arisen that allow these challenges to be addressed through irrigation controllers guided by irrigation and crop simulation models. Remote control systems are often installed in collective pressurized irrigation networks. Agrometeorological information networks are available in regions worldwide. Water users’ associations use specialized databases for water management. Different configurations of irrigation controllers based on simulation models can develop, continuously update, and execute irrigation schedules aiming at maximizing irrigation adequacy and water productivity. Bottlenecks requiring action in the fields of research, development, and innovation are analyzed, with the goal of establishing agendas leading to the implementation and commercial deployment of advanced controllers for solid-set irrigation.Peer ReviewedSprinkler irrigationControlModelsIrrigation systemsIrrigation districtsPublishe

From on-farm solid-set sprinkler irrigation design to collective irrigation network design in windy areas

The definitive version is available at: http://www.sciencedirect.com/science/journal/03783774In this paper, a contribution to the design of collective pressurized irrigation networks in solid-set sprinkler irrigated windy areas is presented. The methodology is based on guaranteeing minimum on-farm performance, using a historical hourly wind speed database and a ballistic solid-set irrigation simulation model. The proposed method was applied to the Montesnegros Irrigation District (central Ebro basin, Spain). The district irrigates an area of 3,493 ha using an on-demand schedule. The average wind speed in the area is 2,8 m s-1. An analysis of district water records showed that farmers often reduce water demand when the wind speed is high, but their irrigation decision making is limited by the capacity of the irrigation network and by the unpredictable character of local winds. Simulations were performed for eleven irrigation seasons, two triangular sprinkler spacings (18x18 and 18x15 m), and two sprinkler models. The percentage of monthly suitable time for irrigation was determined for four management strategies. The first one was based on a wind speed threshold (3 m s-1), while the other three were based on three levels (standard, relaxed and restrictive) of two irrigation performance parameters: the Christiansen Uniformity Coefficient (CU) and the Wind Drift and Evaporation Losses (WDEL). The thresholds for the standard strategy were CU ≥ 84% and WDEL ≤ 20%. The suitable time for the first strategy (56%) was always lower than for the standard and the relaxed strategies (with respective average values of 75 and 86%), and higher than for the restrictive strategy (30%). In order to design the collective network, the hydrant operating time was equalled to the suitable time for irrigation. The differences in the cost of the collective network plus the on-farm equipment were particularly relevant between the restrictive strategy and the other three. Differences in suitable operating time were clear between sprinkler spacings, and less evident between sprinkler models. The application of the proposed methodology may be limited by the availability of historical wind speed records and CU estimates for different combinations of sprinkler models, sprinkler spacings and wind speed.CICYT of the Government of Spain (grant AGL2004-06675-C03-03/AGR) Government of Aragón (grant PIP090/2005)Peer reviewe

Evaluación de los riegos de la Comunidad de Regantes V del Canal de las Bardenas

14 Pag., 2 Tabl., 1 Fig.[ES] En este artículo se presentan los resultados de las evaluaciones de riego que se han llevado a cabo dentro de la segunda fase del trabajo denominado “Mejora de la Gestión Integral del Agua de Riego en la Comunidad de Regantes V del Canal de Bardenas”. El 80 % de la superficie de esta comunidad está ocupado por suelos de plataformas residuales, mientras que el resto son suelos de aluvial. Para caracterizar la capacidad de retención de agua de los suelos (CRA) se realizó un muestro en el que se describieron 50 perfiles. Para determinar la infiltración de los suelos y los índices de calidad del riego por superficie se realizaron 50 evaluaciones de riego. Un adecuado manejo del agua a nivel de parcela y unas texturas francas-franco arenosas permiten alcanzar niveles de eficiencia medios en las parcelas de las plataformas (53 % de media), cuyos suelos se caracterizan por una baja CRA (60 mm de media). En aluviales la eficiencia llega hasta un 80 % de media, gracias a las elevadas capacidades de retención de agua de estos suelos (182 mm de media). Actualmente se está realizado un reaprovechamiento de las aguas de desagüe que posiblemente provoque que la eficiencia a nivel de comunidad sea mayor que la obtenida a nivel de parcela. Estos resultados permiten pensar que la modernización de los regadíos, mediante el cambio a un sistema de riego presurizado, tendría un fuerte impacto sobre la eficiencia en parcela, aunque el impacto sobre la eficiencia en la comunidad sería menor. La modernización tendría resultados muy beneficiosos social y económicamente para los agricultores, además de mejorar la calidad de las aguas de los ríos que atraviesan la comunidad.[EN] Results of the irrigation evaluations performed in the second phase of the project “Improvement of the Water Irrigation Integral Management in the Comunidad de Regantes V del Canal de Bardenas” are presented in this paper. An 80 % of the area of the Irrigation District is occupied by soils of residual platforms, and the rest of the soils are alluvial. A soil survey was performed for characterising the water holding capacity (WHC) of the soils, using 50 soil profiles. A total of 50 irrigation evaluations was performed for determining soil infiltration and the performance indexes of surface irrigation in the study area. An adequate water management in border irrigation and loam-sandy loam textures permit to attain 53 % application efficiency in platforms, whose soils are characterized by a low WHC (with an average of 60 mm). In alluvial soils the application efficiency is higher, with an average of 80 %, due to the high water holding capacity of these soils (an average of 182 mm). Currently, The district is enforcing a program for irrigation return flows reuse. This program surely results in an irrigation district efficiency substantially higher that the average application efficiency. With these results is possible to think that an irrigation modernization, through a change to a pressurized irrigation system will severely improve the application efficiency, but the effect on the irrigation district efficiency will only be moderate. However, this modernisation would have great social and economical benefits for farmers, and also, the water quality of rivers crossing the irrigation district will be improved.Este proyecto de investigación ha sido cofinanciado por la CICYT, por Fondos FEDER, por el CONSI+D y por la Comunidad de Regantes V de Bardenas.Peer reviewe

La contabilidad del agua aplicada al análisis de la modernización de riegos del Alto Aragón

8 páginas, 3 figuras, 2 tablas.-- Artículo técnico.En este artículo se aplica la contabilidad del agua, según los conceptos expuestos en “La necesidad de mejorar la contabilidad del agua en el regadío: el caso de la cuenca del Ebro”, publicado en la edición 168 de Riegos y Drenajes XXI. La especialización productiva de la zona regable de Riegos del Alto Aragón (RAA) son los cultivos extensivos. En el 73% de sus 123.354 ha de superficie se riega con antiguos sistemas de riego por gravedad, mientras que en el resto se utilizan sistemas presurizados, con un predominio casi total del riego por aspersión. La demanda de agua por unidad de superficie regable es similar en ambos tipos de riego, sin embargo, el consumo de agua es superior en el riego por aspersión, dada su mayor evapotranspiración productiva (cultivos) y no productiva (pérdidas por evaporación y arrastre). La modernización de esta zona regable está sustituyendo el riego por gravedad por la aspersión, manteniendo la producción de cultivos extensivos, aunque con una intensificación de las producciones de alfalfa y maíz. Esto conducirá a un aumento del consumo del agua, y por tanto a una disminución de su disponibilidad aguas abajo de esta zona regable. La disminución de la escorrentía/ percolación reducirá las masas exportadas de contaminantes como sales y agroquímicos, mejorando la calidad de las aguas. La productividad económica bruta por unidad de superficie se incrementará, aunque apenas variará la productividad del agua consumida, debido al mantenimiento de los cultivos extensivos y a la adopción del sistema de riego por aspersión.Peer reviewe

Consecuencias de la modernización del regadío sobre el aprovechamiento del agua en Riegos del Alto Aragón

14 Pag., 3 Tabl., 3 Fig.[ES] ¿Será suficiente la modernización del regadío para abordar las incertidumbres que plantea el futuro del sector agrario?; ¿La mejora de la productividad que se obtenga permitirá afrontar el pago de la inversión ante los continuos incrementos de precios de los factores de producción?; ¿Se ahorrará suficiente agua para ser menos sensibles a situaciones de sequía?. La modernización es un proceso necesario para mejorar la situación del regadío español. Sin embargo, plantea incertidumbres en grandes zonas regables del interior orientadas a la producción de cultivos herbáceos extensivos. Este trabajo pretende proporcionar una primera aproximación a estas cuestiones en la zona regable de Riegos del Alto Aragón. A partir de los datos disponibles en su sistema de gestión basado en ADOR se ha analizado la situación actual del aprovechamiento del agua, y la posible repercusión que tendrá la modernización. Los resultados muestran cómo la modernización no va a suponer un ahorro neto de agua en la cuenca. La modernización mejorará la productividad económica garantizando la sostenibilidad de las explotaciones si se aprovecha la flexibilidad de las nuevas infraestructuras para diversificar los cultivos y realizar un uso más productivo del agua.[EN] Will the modernization of irrigation systems be enough to face the uncertainties of the agrarian sector?; Will the improvement of productivity achieved allow to pay back the required investments in a context of progressive increase of input costs?; Will the water saving achieved be enough to reduce the sensitivity to water shortages? The modernization of irrigation systems is a necessary process to improve the Spanish irrigation sector. Nevertheless, it raises uncertainties in continental irrigated areas specializing in field crops. In this paper, preliminary answers to these questions are presented for the Riegos del Alto Aragón project (central Ebro basin, Spain). Current water use and the impact of modernization have been analyzed using the management database ADOR, which is widely used in this area. The modernization of irrigation systems will not result in net water saving for the watershed. Modernization will increase the economic productivity that can guarantee the sustainability of farming systems if the flexibility of the new hydraulic structures is used to diversify crops and to make a more productive use of water.Peer reviewe

Field test of an automatic controller for solid-set sprinkler irrigation

13 Págs., 4 Figs., 5 Tabls. The definitive version is available at: http://link.springer.com/journal/271The application of new technologies to the control and automation of irrigation processes is becoming very important, and the automatic generation and execution of irrigation schedules is receiving growing attention. In this paper, a prototype automatic irrigation controller for solid-set systems is presented. The device is composed by software and hardware developments. The software was named Ador-Control and it integrates five modules: the first four modules simulate drop trajectories, water distribution, crop growth and yield, and the last module ensures bidirectional communication between software and hardware. Decision variables based on soil, crop, and irrigation performance indexes were used to make real-time irrigation decisions. A randomized experimental design was designed to validate the automatic controller over a corn crop during two seasons. Three treatments were analyzed: T0) manual programmer or advanced farmer; T1) automatic scheduling controlled by indexes based on soil simulated water content and irrigation performance; and T2) advanced automatic scheduling controlled by simulated thresholds of crop and irrigation indexes. Experimental results in 2009 and 2010 indicated that automatic irrigation treatments resulted in similar maize yield but using less water than manual irrigation (10 % between T0 and T1, and 18 % between T0 and T2). © 2012 Springer-Verlag Berlin Heidelberg.This research was funded by the MCINN of the Government of Spain through grants AGL2007-66716-C03-01/02 and AGL2010-21681-C03-01Peer reviewe