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37 Pags., 6 Figs., 3 Tabls. The definitive version is available at: http://www.sciencedirect.com/science/journal/15375110 ; The radial water distribution and irrigation performance of an agricultural sprinkler with plastic nozzles were analysed. Twenty-six tests with an isolated sprinkler corresponding to different combinations of three working pressure (p, 200, 300 and 400kPa) and three nozzle diameters of the main nozzle (4.0, 4.5 and 5.0mm) were performed to evaluate the radial water distribution curves, All the tests were performed under calm wind (≤1ms-1) under open air conditions. Fifty tests corresponding to six combinations of nozzle diameter and pressure with the same sprinkler model were performed under a wide range of meteorological conditions in a rectangular solid-set system at 18m×18m sprinkler spacing to evaluate the Christiansen's Uniformity Coefficient (CUC) and wind drift and evaporation losses (WDEL). The resulting radial water distribution curves were compared with those from impact sprinklers with brass nozzles. Sprinkler model had an important effect on the radial water distribution, even under similar operational conditions, and these differences were shown in the first 2.5-6m from the sprinkler. The CUC and WDEL of a solid-set sprinkler system were compared with simulated values from the >Ador-Sprinkler> model. The results of this analysis showed that the type of sprinkler had a moderate influence on sprinkler irrigation uniformity. The analysis presented in this study may serve to develop a decision tool to choose the most suitable combinations of sprinkler model, nozzle diameter and working pressure to optimise the uniformity and efficiency of sprinkler irrigation. ; This research was funded by the MCINN of the Government of Spain through grants AGL2007-66716-C03-01/02, AGL2010-21681-C03-01/03; the European Commission through grant QUALIWATER (INCO-CT-2005-015031) and by the FPI-MICINN PhD grants programme. ; Peer Reviewed

36 Pags.- 4 Tabls.- 7 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/03783774 ; An important modernization process providing pressurized irrigation systems to the traditional surface irrigation districts has taken place in Spain over the last 20 years However, an adverse consequence of modernization is the important increase in the energy cost in the modernized irrigation districts, which is aggravated by the current high energy prices. The Almudévar irrigation district (AID), a traditional surface irrigation district, was transformed into a pressurized sprinkler irrigation system in late 2010. The irrigation network was equipped with a high-level telemetry and remote control system that reaches the hydraulic valves of the irrigated blocks into which the plots are divided. Therefore, the telemetry system enables the centralized management of the irrigation scheduling from the district office. The district is divided into four independent networks with their own reservoirs and electric pump stations. A comparison of the land structure, crop patterns and irrigation management between the modernized AID in 2011 and the pre-modernization AID in 2006-2008 was performed. The temporal evolution of the irrigation water and energy demands in the 2011 irrigation season was analyzed with the available telemetry data from 2011. An irrigation performance index (SIPI) of the monthly and seasonal frequencies was computed for the main crops of the AID. Most irrigation events were performed during the low electricity tariff periods (P6 electric tariff) due to the centralized irrigation scheduling. Meteorological constraints had a low incidence in irrigation scheduling. Generally, a slight decrease in total irrigation deliveries was observed before and after medium-to-large precipitation events, but no changes in irrigation deliveries was observed with increases in wind speed. The exploitation of telemetry data in the AID has been an important tool to optimize the contracted electricity power in each tariff period and in decreasing the electric bill of the AID. This type of telemetry data analysis, similar to the analysis performed in the modernized AID in 2011, could be used in other water use associations as an important decision-making tool to improve water and energy management and to control the irrigation cost. ; This research was funded by the MCINN of the Government of Spain through grants AGL2007-66716-C03-01/02 and AGL2010-21681-C03-01/03; European Commission through grant QUALIWATER (INCO-CT-2005-015031) and by FPI-MICINN PhD grants program. ; Peer reviewed

47 Pags., 7 Tabls., 6 Figs. The definitive version is available at: http://ascelibrary.org/toc/jidedh/138/6 ; Over the last 10 years, telecontrol systems have been incorporated into the majority of modern collective pressurized irrigation networks in Spain. This type of infrastructure provides many opportunities for irrigation management but actually, in Spain, is only used for standardized network operations. The Candasnos irrigation district (CID), located in northeastern Spain, is equipped with this system, and contains a variety of different pressurized systems. Telecontrol data and crop water requirements were used to analyze the evolution of irrigation performance (SIPI) of maize, alfalfa, and stone fruits. Irrigation guidelines for stone fruit were analyzed and compared with those of standard and regulated deficit irrigation (RDI) irrigation strategies. Ten solid-set irrigation systems were monitored to determine on-farm irrigation patterns. The average SIPI of maize, alfalfa, and peach was 83, 107, and 123%, respectively. The average SIPI showed a high irrigation performance, but the spatial and temporal variability of SIPI showed possibilities for improvement. Deficit irrigation practices were conducted on peach trees but not adjusted to the recommended RDI strategy. The results of plot monitoring showed crop differences on irrigation time per event (1–1.5 h in maize and 2–3 h in alfalfa) and on time interval between irrigation (larger in alfalfa than in maize). The short and frequent irrigation timing for the corn crop could be a disadvantageous practice because it yielded high evaporation losses from crop-intercepted water. Two irrigation patterns were established at the CID: the first was characterized by structured irrigation schedules and the second was characterized by weekly changes in the irrigation schedule. The second pattern was more commonly employed in solid-set systems than in those with pivots. The analysis of telecontrol data following this methodology could be easily implemented in the daily routines of the district office to improve irrigation management at the plot level. Further, telecontrol data can be an important tool for promoting and facilitating regulated deficit irrigation strategies in stone fruits. ; This research was funded by the MCINN of the Government of Spain through grants AGL2007-66716-C03-01/02, AGL2010-21681-C03-01/03; the European Commission through grant QUALIWATER (INCO-CT-2005-015031) and by the FPI-MICINN PhD grants program. ; Peer reviewed

49 Pags., 3 Tabls., 6 Figs. The definitive version is available at: http://link.springer.com/journal/271 ; Gross sprinkler evaporation losses (SELg) can be large and decrease irrigation application efficiency. However, it is not universally established how much of the SELg contributes to decrease the crop evapotranspiration during the sprinkler irrigation and how much are the net sprinkler losses (SELn). The components of SEL were the wind drift and evaporation losses (WDEL) and the water intercepted by the crop (IL). The gross WDEL (WDELg) and evapotranspiration (ET) were measured simultaneously in two alfalfa (Medicago sativa L.) plots, one being irrigated (moist, MT) and the other one not being irrigated (dry, DT). Catch can measurements, mass gains and losses in the lysimeters and micrometeorological measurements were performed to establish net WDEL (WDELn) during the irrigation and net IL (ILn) after the irrigation as the difference between ETMT and ETDT. Also, equations to estimate ILn and net sprinkler evaporation losses (SELn) were developed. ILn was strongly related to vapor pressure deficit (VPD). SELn were 8.3% of the total applied water. During daytime irrigations, SELn was 9.8% of the irrigation water and slightly less than WDELg (10.9%). During nighttime irrigations SELn were slightly greater than WDELg (5.4% and 3.7%, respectively). SELn was mainly a function of wind speed. ; This research was funded by the MCINN of the Government of Spain through grants AGL2007-66716-C03-01/02, AGL2010-21681-C03-01/03; the European Commission through grant QUALIWATER (INCO-CT-2005-015031) and by the FPI-MINECO PhD grant program. ; Peer reviewed