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9 Pags., 3 Figs., 2 Tabls. The definitive version is available at: http://www.sciencedirect.com/science/journal/18780296/19/supp/C ; This paper describes a new method (NSQE) to estimate soil hydraulic properties (sorptivity, S, and hydraulic conductivity, K) from full-time cumulative infiltration curves. The technique relies on an inverse procedure involving the quasi-exact equation of Haverkamp et al. (1994). The numerical resolution is described and the sensitivity of the method is theoretically evaluated, showing that the accuracy of the estimates depends on the measured infiltration time. A new procedure to detect and remove the effect of the contact sand layer on the cumulative infiltration curve is also given. The method was subsequently compared to the differentiated linearization procedure (DL), which calculate K and S from the simplified Haverkamp et al. (1994) equation, valid only for short to medium times. A total of 264 infiltration measurements performed with a 10cm diameter disc under different soil conditions were used. Compared to the DL procedure, field measurements showed that the NSQE method allowed better estimates of soil hydraulic properties, independently on the infiltration noise and the presence of contact sand layer. Overall, although comparable S values were estimated with both methods, the longer infiltration times allowed by the proposed method made this procedure more accurate estimations of K. In conclusion, the NSQE method have shown to be a significant advance to accurate estimate of the soil hydraulic properties form the transient water flow. ; This research was supported by the Ministerio de Ciencia e Innovación of Spain (Grant AGL2010- 22050-C03-02) and by the Aragón Regional Government and La Caixa (Grant 2012/GA LC 074). ; Peer reviewed

45 Pags.- 3 Tabls.- 10 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/03783774 ; Water application depth of a center-pivot (CP) irrigation system is not uniformly distributed across a field due to emitter package design, tower dynamics, and meteorological variability. The objective of this research was to measure and model the effect of the intra-irrigation meteorological variabilities on CP seasonal water distribution pattern and corn yield. The 2013 irrigation season of a commercial CP cropped with corn was analyzed. From 60 irrigation events applied to the corn, 10 were evaluated using radial catch cans. The mechanical movement of CP towers for the sixty irrigation events was characterized using Global Navigation Satellite System-Real Time Kinematic (GNSS-RTK) monitoring. Meteorological variables at 1 s frequency were measured with an automatic weather station installed in the farm. The ballistic model calibrated and validated for rotating spray plate sprinklers under different nozzle sizes and wind conditions was mounted on the CP lateral, following the correspondent sprinkler package. The CP lateral was moved following the measured or simulated tower dynamic, and the current or averaged meteorological conditions of each irrigation event were applied to the corn. Crop yield was simulated by coupling the water distribution pattern simulated under the different cases with the Ador-crop model. Differences were observed for simulated seasonal water distribution pattern of the CP under homogeneous wind conditions (averaged for each irrigation event) or under variable of time wind conditions (measures). Simulated yield considering discontinuous tower dynamics and intra-irrigation meteorological variability has the largest correlation coefficient with the measured corn yield. Other factors were not considered in the yield simulation as variability in nutrient availability, emergence problems, and diseases and soil variability could explain the differences between the simulated and measured corn yield. The intra-irrigation meteorological variability has an important effect on the water distribution pattern of windy irrigation events of CP systems. Depending on the wind speed along the crop season, the intra-irrigation variability will have a major or minor effect on seasonal water distribution pattern and crop yield variability. ; This research was funded by the Ministry of Economy and Competitiveness of the Spanish Government through the grants AGL2010-21681-C03-01 and AGL2013-48728-C2-1-R. ; Peer reviewed

53 Pags.- 16 Figs. The definitive version is available at: http://ascelibrary.org/journal/jhend8 ; Fast flows and avalanches of rock and debris are among the most dangerous of all landslide processes. Understanding and predicting postfailure motion (runout) of this kind of flowlike landslides is thus key for risk assessment, justifying the development of numerical models able to simulate their dynamics. In this paper a numerical method for the resolution of the depth-averaged debris flow model is presented. This set of nonlinear differential equations is formed by a variation of the shallow water equations, including strong bed slope, and a rheology resistance term. This paper focus on the numerical discretization of the resistance term, exploring three different approximations: pointwise, implicit, and unified. Well balance between numerical flux and source terms is only achieved using the unified discretization. In order to avoid nonphysical values of the water depth and discharge, a limitation of the unified resistance term is also needed. This correction is made following three conditions that identify the physical boundaries of the resistance term in the debris flow. This technique does not affect the computational efficiency of the method, keeping the original time step. Furthermore, proposed analytical test cases show that the three resistance limitations do not significantly perturb the numerical solution. The properties of the resulting numerical scheme are studied using a set of numerical experiments that include steady and transient flows. The results show the convenience of the unified discretization and the need of the three-condition limitation in order to avoid unphysical solutions. ; This research was supported by project Changing RISKS(OPE00446/PIM2010ECR-54900726)financed by EU FP7 ERANET CIRCLE Programme,and Grupo de Excelencia E68550 financed by the Aragón Government and the European Social Fund(ESF). ; CIRCLE Project reference:SSA-011793 ; Peer reviewed

56 Pags.- 5 Tabls.- 8 Figs. The definitive version is available at: https://www.sciencedirect.com/science/journal/03783774 ; Simulation models of sprinkler irrigation are a valuable tool to improve the irrigation water management at plot scale. Ballistic theory has been commonly used to simulate drop dynamics in sprinkler irrigation models. A number of experiments on sprinkler irrigation performed in previous studies in the Ebro Valley Spain were analyzed and integrated in a data base. The evaluations were performed on six sprinkler types with different nozzle sizes, operating pressures under different meteorological conditions and spacings. The data base includes 40 isolated and 167 solid-set experiments that were processed with a self-calibrated model to calibrate and validate the ballistic parameters. The ballistic model used in this research was improved with respect to a previous model, moreover some novelties were added. These modifications were done in the phases of: the numerical solution, a wind drift and evaporation losses model, simulations considering slope in the terrain, drop generation (using regular and random methods), the size of the terrain cells where the drops are simulated and considering two drop size distributions, upper limit lognormal and Weibull. The results indicated larger and significant differences of Christiansen´s Uniformity Coefficient measured and simulated when considering a constant wind velocity (9%) and no differences when the wind velocity is defined for intervals equal to or less than 30 min (6%). Regarding the effect of the slope in the terrain, differences between both uniformity coefficients are relevant (11%) when the wind velocity is larger than 4 m s−1. Both drop size distributions were similar in accuracy however, the upper limit lognormal was more suitable to simulate a sprinkler especially designed to operate under low pressure. The predictive ability of the model once calibrated and validated was satisfactory (99% and 75%, respectively). The new model improves the accuracy with respect to previous research and minimizes the computing time for the calibration and validation processes using the cluster Trueno-CSIC. ; This research was funded by MICINN of the Government of Spain through grant AGL2013-48728-C2-1-R and AGL2017-89407-R. Octavio Robles received a scholarship granted by the Minister of Economy and Competitiveness of the Spanish Government. ; Peer reviewed

sta comunicación presenta varios avances realizados en la t écnica de infiltrometría de tensión. (i) Nuevas bases de disco que permiten medidas de infiltración sin utilizar arena de contacto (disco de base adaptable) o sobre cobertura vegetal (base con forma de sombrero). (ii) Estimación de la conductividad hidráulica (K) y sorptividad (S) del suelo a partir de la solución numérica de la ecuación cuasi- analítica de la curva de infiltración acumulada 3D (NSQE). Los resultados muestran que los prototipos presentados permiten medir de forma satisfactoria la curva de infiltración acumulada de agua en el suelo. Paralelamente, el método NSQE aplicado sobre 400 medidas de infiltración ha re sultado ser robusto y ofrece estimaciones más precisas de K y S. ; This research was supported by the Ministerio de Ciencia e Innovación of Spain (grant AGL2010-22050-C03-02) and by the Aragón regional government and La Caixa (Grants: GA-LC020/2010; GA-LC006/2008; 2012/ GA LC 074). T ; Peer Reviewed

45 Pags.- 4 Tabls.- 5 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/00221694 ; Based on the analysis of Haverkamp et al. (1994), this paper presents a new technique to estimate the soil hydraulic properties (sorptivity, S, and hydraulic conductivity, K) from the full-time cumulative infiltration curves. The proposed method, which will be named as the Numerical Solution of the Haverkamp equation (NSH), was validated on 12 synthetic soils simulated with HYDRUS-3D. The K values used to simulate the synthetic curves were compared to those estimated with the NSH method. A procedure to detect and remove the effect of the contact sand layer on the cumulative infiltration curve was also developed. A sensitivity analysis was performed using the water level measurement as uncertainty source and the procedure was evaluated considering different infiltration times and data noise (e.g. air-bubbling in the infiltrometer). The good correlation between the K used in HYDRUS-3D to model the infiltration curves and those obtained by the NSH method (R2 =0.98) indicates this technique is robust enough to estimate the soil hydraulic conductivity from complete infiltration curves. The numerical procedure to detect and remove the influence of the contact sand layer on the K and S estimates resulted to be robust and efficient. A negative effect of the curve infiltration noise on the K estimate was observed. The results showed that infiltration time was an important factor to estimate K. Smaller values of K or lower uncertainty required longer infiltration times. In a second step, the technique was tested in field conditions on 266 different soils at saturation conditions, using a 10 cm diameter disc infiltrometer. The NSH method was compared to the standard differentiated linearization procedure (DL), which estimates the hydraulic parameters using the simplified Haverkamp et al. (1994) equation, valid only for short to medium times. Compared to DL, NSH was considerably less affected by the infiltration bubbling and the contact sand layer, and allowed more robust estimates of K and S. Although comparable S values were obtained with both methods, the NSH technique, which is not limited to short times, resulted in more accurate and robust estimates for K. This paper demonstrates the NSH method is a significant advance to estimate of the soil hydraulic properties from the transient water flow. ; This research was supported by the Ministerio de Ciencia e Innovación of Spain (grant AGL2010-22050-C03-02) and by the Aragón regional government and La Caixa (Grants: 2012/ GA LC 074). ; Peer reviewed

28 Pags.- 5 Figs.- 3 Tabls. The definitive version is available at: http://www.publish.csiro.au/sr ; Estimation of the soil–water retention curve, θ(h), on undisturbed soil samples is of paramount importance to characterise the hydraulic behaviour of soils. Although a method of determining parameters of the water retention curve (α, a scale parameter inversely proportional to mean pore diameter and n, a measure of pore size distribution) from saturated hydraulic conductivity (Ks), sorptivity (S) and the β parameter, using S and β calculated from the inverse analysis of upward infiltration (UI) has been satisfactorily applied to sieved soil samples, its applicability to undisturbed soils has not been tested. The aim of the present study was to show that the method can be applied to undisturbed soil cores representing a range of textures and structures. Undisturbed soil cores were collected using stainless steel cylinders (5 cm internal diameter × 5 cm high) from structured soils located in two different places: (1) an agricultural loam soil under conventional, reduced and no tillage systems; and (2) a loam soil under grazed and ungrazed natural shrubland. The α and n values estimated for the different soils using the UI method were compared with those calculated using time domain reflectometry (TDR) pressure cells (PC) for pressure heads of –0.5, –1.5, –3, –5, –10 and –50 kPa. To compare the two methods, α values measured with UI were calculated to the drying branch of θ(h). For each treatment, three replicates of UI and PC calculations were performed. The results showed that the 5-cm high cylinders used in all experiments provided accurate estimates of S and β. Overall, the α and n values estimated with UI were larger than those measured with PC. These differences could be attributed, in part, to limitations of the PC method. On average, the n values calculated from the optimised S and β data were 5% larger than those obtained with PC. A relationship with a slope close to 1 fitted the n values estimated using both methods (nPC = 0.73 nUI + 0.49; R2 = 0.78, P < 0.05). The results show that the UI method is a promising technique to estimate the hydraulic properties of undisturbed soil samples. ; This research was supported by the Ministerio de Economía y Competitividad of Spain (CGL2014-53017-C2-1-R and CGL2016-80783-R) and Aragon Regional Government and La Caixa (GA-LC020/2010; 2012/ GA LC 074). ; Peer reviewed

31 Pags., 2 Tabls., 10 Figs. The definitive version is available at: http://ascelibrary.org/toc/jidedh/139/7 ; Ballistic simulation has been successfully applied to impact sprinklers. However, ballistic simulation of center pivot sprinkler irrigation has been limited by the difficulty in estimating the initial drop velocity vector in fixed and rotating spray plate sprinklers. Initial velocity is severely affected by the impact of the jet on the sprinkler deflecting plate (or plates). In this work, experimental techniques based on drop photography have been used to obtain the droplet velocity and angle in the vicinity of a fixed spray plate sprinkler by using three different nozzle diameters. Furthermore, simulation techniques based on the inverse solution of drop trajectory were combined to determine the initial velocity vector and energy loss at the spray. Our analysis suggests that the ballistic model can be used to simulate drop inverse trajectory in these sprinklers, although the ballistic model can benefit from 5 to 10% effective drag-force screening. The ratio of initial drop velocity to jet velocity was between 0.67 and 0.82, whereas the kinetic energy losses in the spray sprinklers amounted to 33–55%. ; This research was funded by the National Research, Development and Innovation Plan of the Government of Spain (Plan Nacional de I+D+I) through grant AGL2010-21681-C03-01, and by the Special Intramural Grant 200940I041 of CSIC (funding G. S´anchez Burillo). R. Delirhasannia received a scholarship from the Ministry of Science, Research and Technology 301 of Iran to perform a scientific stay at the Aula Dei Experimental Station of CSIC, Zaragoza, Spain. ; Peer reviewed

41 Pags.- 3 Tabls.- 11 Figs. The definitive version is available at: https://link.springer.com/journal/271 ; More than one million hectares have undergone irrigation modernization in Spain during this century. Irrigation modernization to pressurized systems is currently facing challenges derived from increasing electricity prices and decreasing public subsidies. The economic viability of such projects is compromised, and the number of projects is decreasing. Pressurized collective networks are commonly designed and managed using hydraulic simulation tools and probabilistic hypotheses on hydrant use. In this paper, a simulation tool is presented that widens the scope of the analysis by combining hydraulics with agronomy, agrometeorology, solid-set sprinkler irrigation and economics. The CINTEGRAL software simulates the net benefit of the seasonal operation of a collective pressurized irrigation network. The software incorporates an optimization module for the electricity contract associated with the pumping station. CINTEGRAL runs on a time step of a half-hour, and simulates the irrigation season of a variety of crops. The software was applied to analyze the economic benefit of a Water User Association (WUA) under different design and management scenarios (on-demand, network sectoring and dividing the irrigated area in separate networks). In the studied WUA, the network sectoring scenario provided important energy savings (22%) but negatively affected yield by a similar economic magnitude. The division of the area in two independent networks was the most cost-effective scenario. Network topologies, cropping patterns, market prices, irrigation infrastructure, soil conditions and management rules determine the optimum WUA management options. CINTEGRAL is a comprehensive simulation tool designed to help designers and managers guarantee the economic viability of their projects. ; Research was funded by the Ministry of Economy and Competitiveness of the Spanish Government (Plan Estatal de I + D+i) through Grant AGL2013-48728-C2-1-R. The International Center for Advanced Mediterranean Agronomic Studies of Zaragoza (CIHEAM-Zaragoza) provided an M. Sc. scholarship to Mr. El Habib El Malki. ; Peer reviewed

46 Pags., 3 Tabls., 10 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/01681699 ; Software con manual de uso en: http://hdl.handle.net/10261/45608 ; This paper presents a real-time, on-farm irrigation scheduling software (RIDECO). The software was been designed for stone fruit orchards in the semiarid conditions of Spain. The characterization of stone fruit crop water requirements for the local conditions and under different irrigation strategies is presented. Meteorological data in the study area is collected daily from the SIAR public network of weather stations in an automated fashion. Subsequently, values of cumulative degree-days are computed to identify the stages of fruit growth and crop development. The software allows performing weekly irrigation schedules under standard, regulated deficit irrigation and water restriction conditions. The irrigation scheduling software stands as a valuable tool for on-farm water resources allocation planning. It can be used to forecast the irrigation water required to meet seasonal meteorological, agronomical and managerial scenarios in stone fruit orchards. RIDECO can also be used to plan deficit irrigation strategies in cases of severe water restrictions. The software can be parameterized to adjust to specific varieties and local farming conditions. A variety of graphs assist irrigation managers in their decisions. ; The authors sequence in this paper follows the "first-last-author-emphasis" norm. This research was funded by the Plan Nacional de I+D+i of the Government of Spain through grant RIDECO-CONSOLIDER CSD2006-00067. ; Peer reviewed

The final version is available at: http://www.sciencedirect.com/science/journal/03783774 ; Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterised by a mild salinity (2.5 dS m 1) and an infiltration rate of 5.8 mm day-1. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day-1), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1,874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001-2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency can not be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day-1 was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration. ; This research was funded by the Plan Nacional de I+D+i of the Government of Spain, through grant AGL2000-1775. Olga Pérez Coveta received a scholarship from the Plan Nacional de Formación de Personal Investigador of the Government of Spain. ; Peer reviewed

Pags.- 4 Tabls.- 9 Figs. Available online 11 June 2014. The definitive version is available at: http://www.sciencedirect.com/science/journal/03783774 ; The simulation of center-pivot performance has been the subject of research efforts since the 1960s. Center-pivot models frequently use empirical equations relating pressure and sprinkler radial application pattern. Individual, stationary water application patterns are overlapped and the resulting water application is mapped in the field. Such models use constant tower angular velocity, neglecting the effect of tower alignment. In this work the discontinuous tower movement has been experimentally characterized and modelled, and a complete model has been developed by using a ballistic model of the center-pivot sprinklers considering nozzle diameter, operating pressure and wind speed. A detailed kinetic analysis of a four-tower commercial center-pivot was performed. Each tower was monitored using a high precision GPS, recording tower positions at high frequency. The experimental center-pivot was equipped with fixed spray plate sprinklers (FSPS). Five experimental center-pivot irrigation events were evaluated using catch-cans. The analysis of tower location data permitted to conclude that two key variables (linear speed and switching angle) showed normal distribution patterns. The center-pivot model was validated with catch-can data. Finally, the simulation tool was used to assess the effect of variable tower alignment quality, center-pivot travel speed and wind conditions on irrigation performance. Comparisons were performed in terms of radial, circular and total irrigation uniformity. Results indicate that the observed tower dynamics had no measurable effect on irrigation uniformity. Tower alignment quality started to be relevant when the switching angle lag was equal to or larger than 2°. In the conditions of this analysis, wind speed showed a clear effect on uniformity. As wind speed increased, uniformity first decreased and then increased. Further research is required to generalize these results to other center-pivot sizes and designs (sprinkler packages). ; This research was funded by the Ministry of Economy and Competitiveness of the Government of Spain through grant AGL2010-21681-C03-01. ; Peer reviewed

19 Pags.- 5 Figs.- 2 Tabls. © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license ; Drought monitoring is essential to determine, at short time intervals, the main characteristics of drought events, such as their duration, severity, and spatial distribution. To ensure that drought monitoring represents a useful tool for governmental plans aimed at preventing or minimizing drought impacts, up-to-date information must be instantaneously accessible and it must provide high spatial and temporal resolution. This study presents a system that allows the automatic tracking of meteorological droughts in the Spanish territory, based on an open and easy-to-use online platform (https://monitordesequia.csic.es/monitor). This drought monitoring system provides two drought synthetic indices: the Standardised Precipitation Index (SPI) and the Standardised Precipitation Evapotranspiration Index (SPEI). Information is provided on a quasi-weekly basis, in a grid format, with a spatial resolution of 1.1*1.1 km, and with data from 1961 to the present time. This drought monitor is updated based on the real-time information gathered from automatic stations, which in turn requires historic information to identify and track drought events. The drought indices are obtained from data processing (quality control, temporal series reconstruction, homogenisation, interpolation, and validation) using climatic variables (maximum and minimum temperatures, solar radiation, rainfall, dew point, and wind speed) which are provided by the Spanish Meteorology Agency and the Ministry of Agriculture of the Spanish Government. We performed a validation of the drought indices for the whole historical period (1961–2020). This allowed us to observe a strong spatial agreement between the indices obtained with the historical dataset and the indices from the monitoring dataset, especially for mainland Spain and the Balearic Islands (Pearson's r, SPI and SPEI >0.99). The presented real-time drought monitoring system represents a relevant and useful tool that allows for quick and effective actions to prevent and mitigate the effects of drought on society and ecosystems. ; This work was supported by projects PCI2019-103631 financed by the Spanish Ministry of Science and Technology and FEDER and CROSSDRO project funded by AXIS (Assessment of Cross (X) - sectoral climate Impacts and pathways for Sustainable transformation), JPI-Climate co-funded call of the European Commission. ; Peer reviewed

8 Pags.- 3 Figs. © Te Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. ; Climate proxy data are required for improved understanding of climate variability and change in the pre-instrumental period. We present the first international initiative to compile and share information on pro pluvia rogation ceremonies, which is a well-studied proxy of agricultural drought. Currently, the database has more than 3500 dates of celebration of rogation ceremonies, providing information for 153 locations across 11 countries spanning the period from 1333 to 1949. This product provides data for better understanding of the pre-instrumental drought variability, validating natural proxies and model simulations, and multi-proxy rainfall reconstructions, amongst other climatic exercises. The database is freely available and can be easily accessed and visualized via http://inpro.unizar.es/. ; This work was supported by the research projects CGL2017-82216-R, PCI2019-103631 and PID2019- 108589RA-100 financed by the Spanish Commission of Science and Technology and FEDER; CROSSDRO project fnanced by the AXIS (Assessment of Cross (X)- sectoral climate Impacts and pathways for Sustainable transformation), and JPI-Climate co-funded call of the European Commission and INDECIS which is part of ERA4CS, an ERA-NET initiated by JPI Climate, and funded by FORMAS (SE), DLR (DE), BMWFW (AT), IFD (DK), MINECO (ES), ANR (FR) with co-funding by the European Union (Grant 690462). Te research of Nieves Bravo-Paredes has been supported by the predoctoral fellowship PRE2018-084897 from Agencia Estatal de Investigación (Ministerio de Ciencia, Innovación y Universidades) of the Spanish Government. Te Portuguese data search stems partly from the project KlimHist, fnanced by FCT (PTDC/AAC–CLI/119078/2010). ; Peer reviewed