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[EN]Pyrenean glaciers are the largest in southern Europe. Their survival is threatened by climate change, highlighting the significance of their study. This research presents an assessment of changes in the glacierized area and thickness of Pyrenean glaciers from 2011 to 2020, using high-resolution optical satellite, airborne lidar and UAV images. The total glacierized area has shrunk by 23.2% and thickness has decreased on average by 6.3 m. These two variables show no correlation for individual glaciers. Although climatic conditions do not vary much among glaciers, their evolution was heterogeneous during the study period. The smaller glaciers (10 ha) have a more homogeneous response. This can be attributed to the generally larger influence of local topography on the response of the smaller Pyrenean glaciers. There is no sign of slowdown in glacier shrinkage respect to previous decades. This work was supported by the Interreg-POCTEFA project OPCC ADAPYR and Spanish Ministry of Economy and Competitiveness project "CGL2017-82216-R." J. Revuelto is supported by the Grant IJC2018-036260-I. I. Vidaller is supported by the Grant FPU18/04978 and is studying the PhD program in the University of Zaragoza. E. Izagirre and I. Rico are supported by the Grant PPGI19/02 (UPV/EHU) and the Consolidated Research Group IT1029-16 (Basque Country Government). E. Berthier acknowledges support from the French Space Agency (CNES).

42 Pags.- 4 Tabls.- 11 Figs. The definitive version is available at: https://www.sciencedirect.com/science/journal/03783774, Zebra mussel (Dreissena polymorpha) colonies are becoming a real problem in pressurized irrigation networks. The zebra mussel infestation of the 45 Water Users Associations (WUAs) of the Riegos del Alto Aragón (RAA) irrigation project (121 thousand hectares located in northeastern Spain) was assessed during the period of 2013–2017. Maps of WUA infestation stages were produced. A survey of the WUAs made it possible to assess the relevance of certain structural and management practices in the control of zebra mussels. A method to monitor zebra mussel colonization of pressurized collective irrigation networks was presented. The method is based on the combination of pressure measurements at network hydrants and hydraulic simulations. Normalized pressure, estimated as the difference between simulated and observed pressure, should approach zero in all hydrants in a properly characterized, non-infested network. A positive normalized pressure can indicate the presence of zebra mussel colonies. The methodology was validated using two different test cases located in two RAA WUAs: the first case involved a discrete chemical treatment, while the second case was based on the analysis of three years of telemetry pressure data and remote operation of network hydrants. The existence of an infested reservoir upstream of the WUAs was the most likely source of zebra mussel colonization of the WUA pressurized networks in the RAA project. The desiccation and chemical treatment of the small WUA reservoirs was associated with pest control. The hybrid (measurement-simulation) methodology is able to characterize the presence of zebra mussel colonies in specific reaches of pressurized irrigation networks., This work was supported by the European Agricultural Fund for Rural Development (EAFRD) and by the Government of Aragón. Both institutions funded the IRRIZEB (Programa integral para el control y mitigación del impacto de la plaga de Mejillón Cebra en sistemas de regadío) grant of the Plan de Desarrollo Rural (PDR).

This work combines very detailed measurements from terrestrial laser scanner (TLS), groundbased interferometry radar (GB-SAR) and ground-penetrating radar (GPR) to diagnose current conditions and to analyse the recent evolution of the Monte Perdido Glacier in the Spanish Pyrenees from 2011 to 2017. Thus, this is currently one of the best monitored small glacier (

Producción Científica, This paper analyzes the evolution of the Monte Perdido Glacier, the third largest glacier in the Pyrenees, from 1981 to the present. We assessed the evolution of the glacier's surface area by analysis of aerial photographs from 1981, 1999, and 2006, and changes in ice volume by geodetic methods with digital elevation models (DEMs) generated from topographic maps (1981 and 1999), airborne lidar (2010) and terrestrial laser scanning (TLS, 2011, 2012, 2013, and 2014) data. We interpreted the changes in the glacier based on climate data from nearby meteorological stations. The results indicate that the degradation of this glacier accelerated after 1999. The rate of ice surface loss was almost three times greater during 1999–2006 than during earlier periods. Moreover, the rate of glacier thinning was 1.85 times faster during 1999–2010 (rate of surface elevation change = −8.98 ± 1.80 m, glacier-wide mass balance = −0.73 ± 0.14 m w.e. yr−1) than during 1981–1999 (rate of surface elevation change = −8.35 ± 2.12 m, glacier-wide mass balance = −0.42 ± 0.10 m w.e. yr−1). From 2011 to 2014, ice thinning continued at a slower rate (rate of surface elevation change = −1.93 ± 0.4 m yr−1, glacier-wide mass balance = −0.58 ± 0.36 m w.e. yr−1). This deceleration in ice thinning compared to the previous 17 years can be attributed, at least in part, to two consecutive anomalously wet winters and cool summers (2012–2013 and 2013–2014), counteracted to some degree by the intense thinning that occurred during the dry and warm 2011–2012 period. However, local climatic changes observed during the study period do not seem sufficient to explain the acceleration of ice thinning of this glacier, because precipitation and air temperature did not exhibit statistically significant trends during the study period. Rather, the accelerated degradation of this glacier in recent years can be explained by a strong disequilibrium between the glacier and the current climate, and likely by other factors affecting the energy balance (e.g., increased albedo in spring) and feedback mechanisms (e.g., heat emitted from recently exposed bedrock and debris covered areas)., Ministerio de Economía, Industria y Competitividad - IBERNIEVE (project CGL2014-52599-P), Ministerio de Agricultura y Pesca, Alimentación y Medio Ambiente (project 844/2013)

This report details the preliminary results of the research focused on Roman archaeological heritage in the Middle Ebro Valley (Spain). The principal objective of this project was to obtain several different readings by means of a UAV equipped with different sensors. Firstly, it has been possible to obtain accurate maps, 3D models and digital elevation models of the site. Secondly, it has been possible to investigate and define archaeological remains still underground, via a new methodology which utilises visible and near-infrared wavelengths.

The suitability of using 3-D laser technology to assess the performance of a twin disc centrifugal fertiliser spreader was analysed. A static test with an Amazone ZA-M twin disc fertiliser spreader distributing di-ammonium sulphate was developed. The spreader was adjusted to spread the fertiliser at a distance of 12 m at three different rates. The test was conducted inside a building; 64 sample boxes were installed on the floor within a 2 m × 2 m frame. Considering the static test, for each spreading rate, five consecutive measurements were made using a Leica HDS6000 3D laser scanner. The information supplied by the laser scanner was correlated with the weight of the fertiliser collected in the boxes using linear regression equations. Each regression model was obtained for one particular and specific spreading configuration. This reduces the applicability of the method because for each spreader setting requires a new surface distribution to be measured to establish a new regression model. A field test was conducted to obtain a fertiliser distribution curve, with the machine set at 41.1 kg min −1 , while the tractor was progressing at 8 km h −1 . This information was used to validate the laser technology by comparing the real distribution curve with the simulated curve. The correlation coefficient (adjusted R 2 ) was 0.86. The information provided by the scanner also enabled the surface distribution of the product, the maximum spreading distance, the spreading symmetry on both sides of the machine and the trajectory of the grains of fertiliser to be analysed.

A methodology for the regulation of boom sprayers working in circular trajectories has been developed. In this type of trajectory, the areas of the plots of land treated by the outer nozzles of the boom are treated at reduced rates, and those treated by the inner nozzles are treated in excess. The goal of this study was to establish the methodology to determine the flow of the individual nozzles on the boom to guarantee that the dose of the product applied per surface unit is similar across the plot. This flow is a function of the position of the equipment (circular trajectory radius) and of the displacement velocity such that the treatment applied per surface unit is uniform. GPS technology was proposed as a basis to establish the position and displacement velocity of the tractor. The viability of this methodology was simulated considering two circular plots with radii of 160 m and 310 m, using three sets of equipment with boom widths of 14.5, 24.5 and 29.5 m. Data showed as increasing boom widths produce bigger errors in the surface dose applied (L/m(2)). Error also increases with decreasing plot surface. As an example, considering the three boom widths of 14.5, 24.5 and 29.5 m working on a circular plot with a radius of 160 m, the percentage of surface with errors in the applied surface dose greater than 5% was 30%, 58% and 65% respectively. Considering a circular plot with radius of 310 m the same errors were 8%, 22% and 31%. To obtain a uniform superficial dose two sprayer regulation alternatives have been simulated considering a 14.5 m boom: the regulation of the pressure of each nozzle and the regulation of the pressure of each boom section. The viability of implementing the proposed methodology on commercial boom sprayers using GPS antennas to establish the position and displacement velocity of the tractor was justified with a field trial in which a self-guiding commercial GPS system was used along with three precision GPS systems located in the sprayer boom. The use of an unique central GPS unit should allow the estimation of the work parameters of the boom nozzles (including those located at the boom ends) with great accuracy.

Biological invasions are one of the most important components of global change, and have increasing effects on the loss of biodiversity and on human societies as a whole. The difficulties of accurately predicting the fate of a given introduction has led to increased interest in identifying situations where the risk posed by invaders is particularly high. We analyse patterns of plant invasions in arid zones to develop explicit invasion risk protocols. The study zones are five arid regions in three continents: the Mojave and Sonoran Deserts in North America, the Atacama Desert in South America, the Sahara in northern Africa and the Tabernas and Monegros in southwest Europe, (Spain). We test which life-history traits are related to invasiveness in these areas. We use Generalized Linear Mixed Models (GLMM) to model variation between species in invasion success as a function of eight predictors, potentially related to invasiveness: clonality, pollination model, dispersal syndrome, linking to moist soils, seed size, linking to disturbed habitats, salinity tolerance and longevity. We also analyse the differences that exist between the total alien flora in these six areas of the world with respect to the attributes that were considered. From the species perspective, when taxonomic effects were accounted for, only dispersal syndrome and linking to disturbed habitats appeared to be related to the invasive nature of plants. However, if taxonomic effects are not taken into account the variable salinity tolerance is also significantly related. In spite of the fact that the regions have important climatic analogies, there does not appear to be a clear general pattern in the attributes of alien flora, as these are largely dependent on local conditions.

This paper analyzes the evolution of the Monte Perdido Glacier, the third largest glacier of the Pyrenees, from 1981 to the present. We assessed the evolution of the glacier's surface area by use of aerial photographs from 1981, 1999, and 2006, and changes in ice volume by geodetic methods with digital elevation models (DEMs) generated from topographic maps (1981 and 1999), airborne LIDAR (2010) and terrestrial laser scanning (TLS, 2011, 2012, 2013, and 2014). We interpreted the changes in the glacier based on climate data from a nearby meteorological station. The results indicate an accelerated degradation of this glacier after 2000, with a rate of ice surface loss that was almost three-times greater from 2000 to 2006 than for earlier periods, and a doubling of the rate of ice volume loss from 1999 to 2010 (the ice depth decreased 8.98 ± 1.8 m, −0.72 ± 0.14 m w.e. yr−1) compared to 1981 to 1999 (the ice depth decreased 8.35 ± 2.12 m, −0.39 ± 0.1 m w.e. yr−1). This loss of glacial ice has continued from 2011 to 2014 (the ice depth decreased 2.1 ± 0.4 m, −0.64 ± 0.36 m w.e. yr−1). Local climatic changes during the study period cannot explain the acceleration in wastage rate of this glacier, because local precipitation and snow accumulation increased slightly, and local air temperature during the ablation period did not significantly increase. The accelerated degradation of this glacier in recent years can be explained by the lack of equilibrium between the glacier and the current climatic conditions. In particular, the average air temperature increased by at least 0.9 °C in this region since the end of the Little Ice Age (LIA) in the mid-1800s. Thus, this glacier shrinks dramatically during years with low accumulation or high air temperatures during the ablation season, but cannot recover during years with high accumulation or low air temperatures during the ablation season. The most recent TLS data support this interpretation. These data indicated that two consecutive markedly anomalous wet winters and cool summers (2012–13 and 2013–14) led to near zero mass balance conditions, with significant losses of ice in some areas. These anomalous periods could not counteract the dramatic shrinkage that occurred during the dry and warm period of 2011–2012.

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.

[EN] This paper presents the application of a long range terrestrial laser scanner for monitoring snow accumulation and evolution of glaciers in the Pyrenees. With this study we are showing the great potential of the methodology presented for studies in mountain environments, particularly in research related to the cryosphere monitoring in relation to climate variability and the complex topography typical of mountain environments. We present a comprehensive protocol for the acquisition and processing of point clouds measured by a laser scanner (RIEGL LPM-321) for the generation of digital terrain models, in order to compare the models obtained at different times. Thus it is possible to obtain snow thickness and changes of ice thickness. As case studies, results from two small ice masses located in the massif of Monte Perdido and snow accumulation on a small basin located in the Tena Valley are presented. © Universidad de La Rioja., [ES] Este trabajo presenta la aplicación de un láser escáner terrestre de largo alcance para la monitorización de la acumulación de nieve y evolución de heleros en el Pirineo. Con el estudio realizado se muestra el gran potencial de la metodología presentada para estudios en ambientes de montaña, concretamente en investigaciones relacionadas con la monitorización de la criosfera en relación a la variabilidad climática y la topografía compleja propia de ambientes de montaña. Se presenta un protocolo completo para la adquisición y tratamiento de las nubes de puntos medidas por un láser escáner de largo alcance (RIEGL LPM-321) para la generación de modelos digitales del terreno, con el propósito de comparar dichos modelos obtenidos en distintos momentos. Así se obtienen espesores de nieve y cambios de espesor de las masas de hielo. Como casos de estudio se presentan resultados de dos pequeños heleros situados en el macizo de Monte Perdido y la acumulación de nieve en una pequeña cuenca situada en el valle de Tena., Este trabajo ha sido financiado por los proyectos CGL2011-27574-CO2-02 y CGL2011-27536, financiados por el Minsterio de Economía y Competitividad, ACQWA (FP7-ENV-2007-1- 212250), financiado por la Comisión Europea, el proyecto DGA-La Caixa: “Efecto de los escenarios de cambio sobre la hidrología superficial y la gestión de embalses del Pirineo Aragonés”, y el proyecto financiado por la Comunidad de Trabajo de los Pirineos (CTTP01/12): “Creación de un modelo de alta resolución espacial para cuantificar la esquiabilidad y la afluencia turística en el Pirineo bajo distintos escenarios de cambio climático”.

The last ten years have witnessed the introduction of 3D laser scanning technology, along with its derived digital applications, revolutionizing the conceptualization, methodology, and results obtained from the process of data recording, standardization and geometric analysis of cultural heritage. For archaeological heritage, 3D laser scanning data recording is key for the life-like representation and characterization of any site feature. Furthermore, it generates a geometric data archive, which is diachronically reproducible, enabling its use as a control instrument for any alteration in the structure.However, the lack of standards or normalized procedures, both in development and management of the three-dimensional models, has resulted in the under-use of all its resources.Therefore, the aim of this paper is to create a series of standardized procedures that may establish a logical procedure, valid for both scientific purposes and for inter-disciplinary dissemination., Pendant les dernières 10 années l’introduction de la technologie laser scanner 3D et les différentes applications numériques, ont supposé une révolution quant à la conceptualisation, à la méthodologie et aux résultats dans le domaine la documentation, la standardisation et l’analyse géométrique du patrimoine culturel.La documentation du patrimoine archéologique à travers la technologie laser scanner 3D constitue une pièce clé dans la représentation fidèle de tout élément patrimonial, en plus de constituer un véritable dossier documentaire géométrique totalement reproductible diachroniquement, en utilisant également comme outil de contrôle de tout type de modification dans sa structure.Une des difficultés que représente la technologie laser scanner est le post processus et le manque méthodes ou processus normalisés qui permettent la gestion des données qu’il produit. On a détecté un gap scientifique qu’il puisse décrire comment représenter et conceptualiser les données géométriques. Celui-ci sans doute est un des facteurs que freine une plus grande divulgation de la technologie laser scanner comme instrument scientifique. Pour résoudre ce fait, il existe plusieurs points fondamentaux qui requièrent une attention spéciale entre les différentes méthodes de conceptualisation d’un projet :• Interactivité et comparaison de processus de registre en rapport avec d’autres disciplines INGÉNIERIE - INDUSTRIE - ENVIRONNEMENT.• Nouveau langage qui nous permet d’enregistrer la réalité, comme métaphore du terme industriel as built.• Standardisation de processus. Contrôle de qualité et vérification à travers des procédures. Principe d’authenticité.• Processus de démocratisation des résultats de 3D qui fournissent une diffusion et une divulgation, et de cette façon, une compréhension au grand public.• Méthodologie multidisciplinaire dans le processus d’étude coordonnée par un technicien spécialiste.• Adaptation du registre réel à un mécanicien cognitif par une extériorisation virtuelle.Dans ce travail on développe une méthodologie de registre, à travers des différents types techniques et instrumentation, avec un exemple d’intégration virtuelle d’art rupestre dans la Comarca del Matarraña (Teruel, Aragon), avec d’autres fragments extraits de son placement original qui se trouvent dans le Musée Archéologique de la Catalogne (Barcelone).La méthodologie permet la documentation d’abris rupestres dans son contexte, et de les intégrer de la même manière avec d’autres éléments extraits de son environnement naturel. Ce processus est développé à travers une technologie laser scanner combinée et associée avec d’autres techniques (topographie, photogrammétrie et géodésie), au bénéfice d’une analyse scientifique normalisée qui permet de reconstruire virtuellement toutes ses parties, en plus d’effectuer un contrôle périodique de sa structure qui prévoit tout type de pathologie morphologique.Une autre question fondamentale traite de la création d’une base de données normalisée à travers un environnement web 3D – formats type html, pdf 3D, vrml –, dirigé vers une plus grande divulgation du site archéologique de manière graphique et surtout géométrique, qui permet d’une façon rapide et précise la visualisation de tout élément ou d’une partie de sa structure. Pour cela on prétend un développement combiné, qui sert pour une plus grande valorisation et une divulgation de l’information obtenue, et qui contribue en plus à une étude scientifique interdisciplinaire qui résout les différents gaps méthodologiques et de conceptualisation.

33 Pags., 10 Figs. The definitive version is available at: http://www.springerlink.com/content/0342-7188/, A topographic three dimensional scanner is similar to a radiometric total station, but it does not require a reflecting prism and the optical measurement device is motorized and automated. With this device, very large survey data sets can be collected with moderate effort. In this paper, the application of a 3D scanner to surface and sprinkler irrigation research is presented and discussed. In surface irrigation, the scanner was successfully applied to: 1) the survey of soil surface elevation, including furrowed areas; 2) the determination of flow cross sections; 3) surveying the location of the advancing front; and 4) measuring water surface elevation. The device showed some limitations in the measurement range, which was limited to about 35 m for water surface elevation and 50 m for the detail survey of furrowed areas. In sprinkler irrigation, the scanner was applied to the survey of the sprinkler jet and the irrigation drops during their trajectory. The scanner seemed to fail to survey fine drops, since falling drops were rarely scanned in the vicinity of the sprinkler. Despite the reported limitations, the 3D scanner seems to be destined to occupy a relevant place in the irrigation research laboratory., This research was funded by the Plan Nacional de I+D+i of the Government of Spain, through grant AGL2007-66716-C03. We appreciate the cooperation of the surveying company “Scanner Patrimonio e Industria”.

42 Pags.- 1 Tabl.- 12 Figs. The defintive publication is available at: http://link.springer.com/journal/271 The experimental data set used in the paper is OA available (http://hdl.handle.net/10261/127640) The characterization of drops resulting from impact sprinkler irrigation has been addressed by a number of techniques. In this article, a new technique based on low-speed photography (1/100 s) is presented and validated. The technique permits to directly measure drop diameter, velocity and angle. The photographic technique was applied to the characterization of drops resulting from an isolated sprinkler equipped with a 4.8 mm nozzle and operating at a pressure of 200 kPa. Sprinkler performance was characterized from photographs of 1,464 drops taken at distances ranging from 1.5 to 12.5 m. It was possible to analyze separately the drops emitted by the main jet and those emitted by the impact arm. The proposed technique does not require specific equipment, although it is labor intensive. This research was funded by the Plan Nacional de I+D+i of the Government of Spain, through grant AGL2007-66716-C03. Carlos Bautista received a scholarship from the Agencia Española de Cooperación Internacional (AECI).

9 Pags.- 9 Figs.- 4 Tabls. The definitive version is available at: http://ascelibrary.org/journal/jidedh, Microtopography has long been regarded as a key variable affecting basin irrigation performance. This paper reports on the extension of a flat bed two-dimensional basin irrigation model to the simulation of irrigation events in basins with microtopography. The model incorporates the local surface slopes in the x and y directions to the governing set of partial differential equations. Three field experiments were used to validate the extended model. Elevation was measured over irregular grids, and geostatistical techniques were applied to estimate the nodal elevation of the computational grids. Results indicate that inclusion of microtopography improves the estimation of the advance and recession processes and produces lower, more realistic estimates of irrigation performance. To further explore this phenomenon, two numerical experiments were devised consisting of a series of simulations on a level basin with gradually growing microtopography. The times of advance and recession and the irrigation performance indexes are significantly affected by field microtopography, even if laser leveling is used.

43 Pags.- 4 Tabls.- 11 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/03783774, Microtopography has long been recognized as one of the key variables in level-basin irrigation performance, although little effort has been devoted to establish its relevance. In this work, experimental data are used to quantify the influence of microtopography on irrigation performance. An irrigation evaluation was performed on a small level-basin (256 m2) LASER levelled to zero slope. Irrigation depth was gravimetrically measured and estimated at the 49 nodes of a regular network. Data from the irrigation evaluation and a two-dimensional flat-bed model were used to estimate irrigation depth. Irrigation times, soil surface elevation and distance to the inlet were estimated at the same nodes, and a correlation matrix was computed. Results showed that soil surface elevation was highly and significantly correlated with the times of advance (0.725∗∗∗), recession ( −0.815∗∗∗) and opportunity ( −0.852∗∗∗), and with the measured irrigation depth ( −0.583∗∗∗). Distribution uniformity using soil water measurements was 71.0%. Estimates from the irrigation evaluation and the two-dimensional model were 85.3% and 94.9%, respectively. The irrigation evaluation procedure could explain 30∗∗∗% of the measured variability in irrigation depth. A large part of the unexplained variance in measured irrigation depth seems to be due to the spatial variation of infiltration properties. Predictions by the two-dimensional model were not significantly related to the measured values. A simple method was devised to estimate microtopography-adjusted irrigation performance from the results of a flat bed model and the standard deviation of elevation. Microtopography can have an important effect on level-basin irrigation performance. Models not considering this variable may incur large errors when simulating irrigation performance.