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[EN] Agricultural economics Water Programming Models (WPM) has found that irrigators in water scarce areas have a rather inelastic response to water prices, making water pricing cost-ineffective towards water saving. We hypothesize that the predicted water saving performance of pricing is significantly underestimated by issues of model structure, due to the exclusion of deficit irrigation from the set of decision variables available to agents in conventional WPM. To test our hypothesis, we develop a model that integrates a continuous crop-water production function into a positive multi-attribute WPM, which allows us to assess agents¿ adaptive responses to pricing through deficit irrigation. The model is illustrated with an application to the El Salobral-Los Llanos irrigated area in Spain. Our results show that incorporating deficit irrigation as an adaptation option makes the water demand curve significantly more elastic as compared to an alternative model setting where deficit irrigation is precluded. We conclude that ignoring deficit irrigation can lead to a significant underestimation of the cost-effectiveness of water pricing towards water saving.

[EN] The sustainability of agriculture in the Mediterranean climate is challenged by high irrigation water demands and nitrogen fertilizer losses to the environment, causing significant pressure on groundwater resources and groundwater dependent ecosystems. Advanced irrigation technologies and improved fertilizer management have been promoted as key solutions to reduce the agricultural impact on aquatic systems. However, it remains unclear how different irrigation-fertilizer practices perform on the long-term under a highly variable climate, such as the Mediterranean one. Here, we conduct hydrological simulations over a fifty-year period to quantify the magnitude and dynamics of groundwater recharge and nitrogen leaching under five real-case irrigation-fertilizer practices observed in Valencia (eastern Spain). The Valencian Region is the largest citrus-producing region of Europe and current irrigation fertilizer practices reflect the ongoing transformation of irrigation systems from flood to drip irrigation. Our simulations highlight three major implications of the irrigation transformation for groundwater resources. First, the transformation from flood to drip irrigation reduces the recharge fraction (19% vs. 16%) and especially the nitrogen leaching fraction (33%vs. 18%) on the long term. Second, the long-term performance of the two irrigation practices is subject to substantial inter-annual differences controlled by precipitation variability. The sensitivity of recharge and nitrogen leaching to annual meteorological conditions is stronger in drip irrigation, which eventually leads to a similar performance of flood and drip irrigation in wet years if fertilizer inputs are similar. Third, we identify a pronounced year-to-year nitrogen memory in the soil, whereby an enhanced (decreased) nitrogen leaching is observed after anomalously dry (wet) years, affecting the performance of irrigation-fertilizer practices. Overall, the study demonstrates the highly variable nat

[EN] Agricultural irrigation is the major water consumer in the Mediterranean region. In response to the growing pressure on freshwater resources, more efficient irrigation technologies have been widely promoted. In this study, we assess the impact of the ongoing transition from flood to drip irrigation on future hydroclimatic regimes under various climate change scenarios, with a particular focus on actual evapotranspiration and groundwater recharge in the Mediterranean region of Valencia, Spain. Hydroclimatic predictions for the near-term future (2020-2049) and the mid-term future (2045-2074) were made under two emission scenarios (RCP 4.5 and RCP 8.5) using a hydrological model that was forced with data from five GCM-RCM combinations and field-based irrigation volume and frequency observations. Our findings suggest that climate change could lead to statistically significant changes in the regional hydroclimatic regime despite projection uncertainties. Major changes include a statistically significant decrease in mean groundwater recharge of up to -6.6% under flood irrigation and -9.3% under drip irrigation and contrasting changes in mean actual evapotranspiration for flood and drip irrigation in the order of +1% and -2.1%, respectively. Since sustainably available water resources in the Valencia region are entirely allocated, the expected changes and associated uncertainties create a challenging context for future water management. Our simulations further indicate that, rather than climate change, the choice of irrigation technique may have a greater impact on actual evapotranspiration and groundwater recharge. Our findings therefore highlight the importance of considering both climate change and irrigation technique when assessing future water resources in irrigated Mediterranean agriculture.

[EN] The replacement of flood-irrigation systems by drip-irrigation technology has been widely promoted with the aim of a more sustainable use of freshwater resources in irrigated agriculture. However, evidence for an irrigation efficiency paradox emphasizes the need to improve our understanding of the impacts of irrigation transformations on water resources. Here, we developed a distributed hydrological modeling approach to investigate the spatiotemporal effect of flood and drip irrigation on groundwater recharge. The approach recognizes differences in the water balance resulting from the localized application of water in surface drip-irrigated fields and the more extensive application of water in flood irrigation. The approach was applied to the semi-arid Mediterranean region of Valencia (Spain) and calibrated using a multi-objective framework. Multiple process scales were addressed within the framework by considering the annual evaporative index, monthly groundwater level dynamics, and daily soil moisture dynamics. Daily simulations from 1994 to 2015 suggested that, in our hydroclimatic conditions, (a) annual recharge is strongly related to annual rainfall, which had a four times higher impact on recharge than the type of irrigation practice, (b) flood-irrigated recharge tends to exceed drip-irrigated recharge by 10% at annual time scales, (c) however, recharge response to a particular precipitation event is smaller in flood irrigation than in drip irrigation, and (d) 8¿18 rainfall events could generate more than half of the annual recharge in drip and flood irrigation, respectively. Our results highlight the importance of understanding the hydrological dynamics under different irrigation practices for supporting irrigation infrastructure policies.

[EN] Climate services are tools or products that aim to support climate-informed decision making for the adaptation to climate change. The market for climate services is dominated by public institutions, despite the efforts made by the European Commission to increase private enterprise in the market. The business model perspective has been proposed as a framework for enabling market growth through the development of appropriate business models for the provision of climate services. However, there is a lack of structured knowledge on how to approach climate service design and development from a business model standpoint. In this contribution, we first analyze the role of stakeholders in the design and development of climate services and identify opportunities for engaging users in the creation process. Afterwards, we explain our approach to climate service design and development using a business model perspective. To illustrate the proposed approach, we describe the co-creation of a climate service to support the adaptation to climate change of the urban water supply system in Valencia, Spain, and discuss the main findings and lessons learned from applying this approach.

[EN] Climate services were initially established with the aim to make the vast amount of climate data, projections and other climate science output publicly available to support the development of responses to society's vulnerability to climate change. In Europe embraced the concept was not only embraced to provide access to scientific knowledge and reduce vulnerability, but also as an opportunity to promote innovation, business opportunities and employment, highlighting the importance of involving users in developing climate services. However, not only differences in knowledge and skills, but also in framing of climate risks and information needs, pose a serious gap between suppliers and users of climate information, sometimes called the "valley of death". Focusing on urban and rural development at the regional and local level as key areas of application for climate services, the paper characterizes this valley of death and suggests options to bridge the gap. We suggest that reframing of the concept of climate services can help expand their applications and effectiveness, taking local non-climate challenges, opportunities and narratives into account. We provide examples from the European ERA4CS project INNOVA. The current focus of climate service development is very much on digital forms of climate change information. While this may provide a useful "back office" function, active brokerage and mediated transfer of knowledge between public and private actors, face-to-face collaboration between providers and clients ("front office"), and integration of social, economic and non-climate environmental challenges with climate risks can help bridging the "valley of death".

[ES] Las situaciones extremas, y en particular las sequías, constituyen un serio problema ambiental, económico y social en las regiones más meridionales de Europa, siendo un fenómeno recurrente en las cuencas mediterráneas de España, sujetas a una alta variabilidad espacial y temporal de la precipitación y caudales y con alto grado de aprovechamiento del recurso. Las sequías representan un fenómeno natural complejo, difícil de cuantificar e identificar en el tiempo y en el espacio, y para el que no existe una definición universalmente aceptada. Este hecho, unido a la incertidumbre futura respecto a su duración e intensidad por el efecto del cambio climático, hace prioritario avanzar en el conocimiento del impacto del cambio climático en las sequías, a fin de poder diseñar planes para su gestión y la mitigación de los efectos asociados. La presente comunicación tiene por objeto evaluar el impacto potencial del cambio climático en las sequías meteorológicas, agrícolas (edáficas) e hidrológicas del Sistema de Explotación Júcar, el de mayor envergadura de los nueve sistemas de explotación de la Demarcación Hidrográfica del Júcar. Para ello se emplean índices estandarizados para caracterizar los diferentes tipos de sequía, con el fin de disponer de resultados homogéneos para estudiar su incidencia espacial y temporal y obtener correlaciones y desfases entre los diferentes tipos de sequía. La metodología a aplicar se basa en la generación de escenarios futuros de las principales variables meteorológicas con el proceso adecuado (ej. corrección de sesgo en reescalado), la simulación de la hidrología del sistema mediante modelos lluvia-escorrentía, y la caracterización y análisis tanto para el período histórico como para los futuros de las sequías meteorológicas, agrícolas e hidrológicas. Para la simulación hidrológica se ha optado por una cadena de modelos agregados de Témez (Témez, 1977) para cada una de las subcuencas en las que se divide el caso de estudio. Una vez gener

[EN] Soil organic carbon pools have an important role in the maintenance of ecosystems as a source of energy for soil microorganisms. Soil biological and biochemical properties are essential for the decomposition of organic matter. These soil properties can be affected by thinning, which is considered sustainable when the soil properties are maintained or improved. We studied the effects of selective thinning and shrub clearing, performed with an ecohydrological approach, in a marginal Holm oak forest in a semiarid area on soil properties. The effects of thinning (T) were compared with an untreated area (control, C). Fine woody debris was ground into mulch onto the thinned area. Forest floor and mineral soil properties were analyzed between five months and seven years after the thinning. In the forest floor, gravimetric water content (GWc(ff)) and water soluble organic carbon (WSOCff) were analyzed and compared between T and C. In mineral soil, GWC(ms), soil organic carbon (SOC), WSOCms, soil basal respiration (BR), soil microbial biomass carbon (MBC) and soil enzymes (acid phosphatase (Acid PA) and urease (URE)) were analyzed. In the early stage, the results showed slightly higher SOC and WSOms in T likely due to fine woody debris left on the forest floor. However, seven years after the thinning the effects of the thinning on all the studied variables were negligible. All variables showed high spatial-temporal variability. Our results suggest that selective thinning and shrub clearing in the studied site do not affect negatively soil properties when woody debris is left on the forest floor.

[EN] The management of water in systems where the balance between resources and demands is already precarious can pose a challenge and it can be easily disrupted by drought episodes. Anticipated drought management has proved to be one of the main strategies to reduce their impact. Drought economic, environmental, and social impacts affect different sectors that are often interconnected. There is a need for water management models able to acknowledge the complex interactions between multiple sectors, activities, and variables to study the response of water resource systems to drought management strategies. System dynamics (SD) is a modeling methodology that facilitates the analysis of interactions and feedbacks within and between sectors. Although SD has been applied for water resource management, there is a lack of SD models able to regulate complex water resource systems on a monthly time scale and considering multiple reservoir operating rules, demands, and policies. In this paper, we present an SD model for the strategic planning of drought management in the Jucar River system, incorporating dynamic reservoir operating rules, policies, and drought management strategies triggered by a system state index. The DSS combines features from early warning and information systems, allowing for the simulation of drought strategies, evaluating their economic impact, and exploring new management options in the same environment. The results for the historical period show that drought early management can be beneficial for the performance of the system, monitoring the current state of the system, and activating drought management measures results in a substantial reduction of the economic impact of droughts.

[EN] Higher education is continuously evolving to keep up with the challenges posed by the introduction of information and communication technologies (ICT) to education. In this sense, distance learning is booming, with an increasing number of higher education students taking advantage of the flexibility remote learning provides. The School of Agricultural Engineering and Environment (ETSIAMN) of Universitat Politècnica de València (UPV) has been gradually incorporating ICT tools in its bachelor and master degrees for the last two decades. As a result, many college students and university instructors are familiar with ICT techniques. However, the unprecedented COVID-19 crisis has put distance learning in the spotlight like never before, forcing students, faculty, and staff to adapt to the new situation with hardly any preparation time. For that reason, it is convenient to analyse in depth the results and impact of the teaching and evaluation methodologies developed and applied during this critical period, as a way to detect and amend potential inefficiencies in the learning process. The specific goal of this study was to analyse the teaching period during the COVID-19 crisis in ETSIAMN, which covered the spring semester of the academic year 2019-2020. To this purpose, 114 instructors and 274 students were surveyed in July 2020, belonging to four bachelor degrees (agricultural and biological engineering; forestry engineering; food engineering; and biotechnology), and three master degrees (agricultural and biological engineering; forestry engineering, and oenology). Regarding the experimental design for the survey, three main blocks were identified: the first block corresponds to teaching methodologies, comparing students and faculty preferences for distance lecturing; the second block focuses on evaluation modalities and exam configurations; and the final block centers on the difficulties found by both students and lecturers along the adaptation process from conventi

[EN] Marginal semi-arid forests in areas currently affected by climate change are a challenge to forest management, which has to focus on key functional traits that can effectively contribute to resistance under extreme drought. We studied the effects of thinning in a marginal forest by quantifying functional responses relating to growth, carbon and water fluxes. Two experimental plots were established, one thinned in 2012 and the other one left as a control. The environmental conditions varied substantially during the 4-year study period, although dry years predominated. There were signs of dieback in the control with a decreasing inter-annual trend in LAI, as opposed to the treated plots, where LAI by the end of the study almost reached pre-thinning levels. Sap flow and transpiration were greatly enhanced by the treatment, with thinned trees transpiring 22.41 tree(-1) day(-1) in the growing season, about twice the control figures. The seasonal patterns of transpiration and soil moisture were uncoupled, indicating a contribution of deep groundwater to the former flux. In the control, limitations to water and carbon dynamics (canopy conductance) occurred at soil moisture values below 16%, whereas in the thinned trees these limitations appeared when soil moisture dropped below 10%. Overall, oaks' transpiration was enhanced with thinning to the point that stand-water use surpassed that of the control by the second half of the study period, averaging 24% of gross rainfall in both plots. Soil evaporation increased from 12 to 20% of gross rainfall after treatment in the overall period. The treatment had a profound watering effect in this marginal forest, led by fewer trees using the same amount of water as those in the untreated overstocked plot. This research may provide guidelines for ecohydrology-oriented silviculture in stands experiencing tree encroachment and transformation into shrublands that are more prone to global change-induced disturbances.

[EN] Water is the key element that modulates the provision of goods and services together with global/climate stressors affecting semiarid forests. In this sense, there is a need to improve the understanding and quantification of forest and water relationships as affected by forest management. This work addresses this issue by comparing net rainfall (Pn) redistribution into different belowground hydrological processes (BHP) in two forest types after a thinning treatment: a holm oak coppice (HU) and a post-fire Aleppo pine regeneration (CAL). The relative contribution (RI) of forest structure, antecedent soil moisture (¿st), rainfall and meteorological conditions on the BHP was assessed through boosted regression trees models. In both sites, the RI of the forest structure itself was limited (< 10%). However, ¿st, which clearly increased significantly with thinning, received an average RI of 29%. Surface and subsurface lateral flows showed values<1% of gross rainfall (Pg) in either site and were not significantly affected by thinning. On the other hand, soil moisture and drainage were affected by the thinning treatment, although with different extent depending on the site: in the drier site (CAL), the increased Pn in the thinning was mainly allocated into increased soil water content, with very limited improvement in drainage (< 10 mm/year); in contrast, in the wetter continental site of HU, drainage to deeper soil layers was the most remarkable effect of thinning (50 mm/year higher than in control), given the higher ¿st and hence the lower soil water storage available. Thinning also improved the response of BHP during drought, making these processes more elastic and less vulnerable to climatic extremes. The results presented here complement those previously reported on rainfall partitioning in these sites and all together provide a comprehensive understanding of the short-term effect (3¿4 years) of water-oriented silviculture in Quercus ilex and Pinus halepensis low

[EN] Semi-arid forests are water limited environments considered as low-productive. As a result, these forests usually end up unmanaged and abandoned, with the subsequent wild fire risk increasing, water yield decreasing and a general diminishing of the forest resilience. Hydrological-oriented silviculture could be a useful alternative that increases management possibilities by combining forest productivity and water yield. However, the slight water yield increase after forest management together with the low forest productivity, could make this option insufficient for semi-arid forests, and other goods and services should be included and quantified. In this sense, the present study analyzes to what extent semi-arid forest management for water yield results effective and profitable at catchment scale, and how does it improve when it is combined with other benefits such as biomass production and fire risk diminishing. To that end, the effects of forest management of semi-arid Aleppo pine post-fire regeneration stands are analyzed in terms of water yield (TETIS-VEG model), fire risk (KDBY index and FARSITE) and biomass production, at catchment scale. Regarding to water yield, the results confirmed the slight effect of forest management on its increase (average increase of 0.27 +/- 0.29 mm yr(-1)), at the same time that highlighted the role of the upper catchment area as an important water contributor. The management produced 4161.6 Mg of biomass, and decreased in 27 +/- 17% and 25.6 +/- 14.1% the fire risk and fire propagation, respectively. Finally, a simple economic estimation of the management profitability is carried out by means of comparing the Benefit/Cost ratio of the managed and unmanaged scenarios. Both scenarios were always above the unity when just considering water as benefit, although the unmanaged scenario produced a higher ratio, as no management costs are expended. Contrarily, when wildfire was also included into the evaluation, the situation is overt

[EN] Hydrology-oriented forest management sets water as key factor of the forest management for adaptation due to water is the most limiting factor in the Mediterranean forest ecosystems. The aim of this study was to apply Bayesian Network modeling to assess potential indirect effects and trade-offs when hydrology-oriented forest management is applied to a real Mediterranean forest ecosystem. Water, carbon and nitrogen cycles, and forest fire risk were included in the modeling framework. Field data from experimental plots were employed to calibrate and validate the mechanistic Biome-BGCMuSo model that simulates the storage and flux of water, carbon, and nitrogen between the ecosystem and the atmosphere. Many other 50-year long scenarios with different conditions to the ones measured in the field experiment were simulated and the outcomes employed to build the Bayesian Network in a linked chain of models. Hydrology-oriented forest management was very positive insofar as more water was made available to the stand because of an interception reduction. This resource was made available to the stand, which increased the evapotranspiration and its components, the soil water content and a slightly increase of deep percolation. Conversely, Stemflow was drastically reduced. No effect was observed on Runof due to the thinning treatment. The soil organic carbon content was also increased which in turn caused a greater respiration. The long-term effect of the thinning treatment on the LAI was very positive. This was undoubtedly due to the increased vigor generated by the greater availability of water and nutrients for the stand and the reduction of competence between trees. This greater activity resulted in an increase in GPP and vegetation carbon, and therefore, we would expect a higher carbon sequestration. It is worth emphasizing that this extra amount of water and nutrients was taken up by the stand and did not entail any loss of nutrients.

[EN] Water-oriented forest management is an urgent need in semiarid catchments. In the case of low-biomass forests and shrublands, the magnitude, efficiency and temporal duration of thinning effects on rainfall partitioning needs further attention. This work studies the effects of juvenile thinning and shrub clearing on stemflow (Stf), throughfall (Thr) and interception (It) in two low-biomass forests (CAL: post-fire Aleppo pine saplings with 74% of basal area, BA, removed; and HU: evergreen oak coppice with 41% of BA removed), as well as the relative contribution of the event meteorology. The effects are compared with a control plot during the first 3¿4¿years. Stf rate (%) decreased with density and, on a tree scale, it was enhanced by the treatment only in the bigger oaks. Event Thr increased from 55 to 81% and from 68 to 86% of gross rainfall (Pg) for CAL and HU respectively after thinning, resulting in about 15% less intercepted Pg. High evaporative conditions and an open (ventilated) forest structure led to high It rates in the controls when comparing with other studies, thus making the treatments more efficient in net precipitation (Pn) gain (Pg intercepted decreased 17% or 2.3% per unit of LAI or BA removed respectively). In general, depths (mm) were mostly explained (>75%) by the rainfall characteristics of the event (e.g. amount, duration, intensity), with a limited contribution from forest structure (e.g. cover, LAI) and event meteorology (e.g. temperature, wind speed, vapor pressure deficit). On the contrary, when expressed as rates (% of Pg), forest structure and event-meteorology gained importance (explaining 25¿65%), especially in the drier site (CAL). In this site, the low gain in Pn (~25¿mm per year on average) was offset with no temporal dampening during the span of this study, as observed in the wetter site (HU), where plant growth tended to mitigate the effect of the treatment by the end of the study. The results presented here make a contribution

This paper analyzes the consequences of adopting new on-farm irrigation management strategies (lowdischarge rates, long irrigation times and high frequencies) in an existing on-demand and sectorizedpressurized irrigation system in eastern Spain. The sectorized behavior of the network was analyzedusing two criteria: (i) the operating sectors obtained in a first stage by arranging the hydrants dependingon their altitude respecting the pumping station and (ii) the operating sectors obtained by means ofan optimization process. The Simulated Annealing combinatorial metaheuristic optimization techniquewas employed to find the best solution. Random on-demand patterns were generated using a Montecarlosimulation. The hydraulic requirements of the network were analyzed in every scenario by the Epanet2.0 engine. The effect on energy consumption, power requirements and energy costs was assessed takinginto account the electricity tariff billing structure. It was found that reductions in emitter discharge (qe)and Energy consumption (E)-Energy Cost (EC) savings are not inherently related to each other. Certainamounts of E and EC could be saved when the number of sectors and operating time parameters wereproperly selected. Pulsed irrigation in the current scenario showed an energy saving potential of 10.67,6.43 and 6.99% for power capacity, E and EC, respectively.

[EN] Forests play a determinant role in the hydrologic cycle, with water being the most important ecosystem service they provide in semiarid regions. However, this contribution is usually neither quantified nor explicitly valued. The aim of this study is to develop a novel hydroeconomic modeling framework for assessing and designing the optimal integrated forest and water management for forested catchments. The optimization model explicitly integrates changes in water yield in the stands (increase in groundwater recharge) induced by forest management and the value of the additional water provided to the system. The model determines the optimal schedule of silvicultural interventions in the stands of the catchment in order to maximize the total net benefit in the system. Canopy cover and biomass evolution over time were simulated using growth and yield allometric equations specific for the species in Mediterranean conditions. Silvicultural operation costs according to stand density and canopy cover were modeled using local cost databases. Groundwater recharge was simulated using HYDRUS, calibrated and validated with data from the experimental plots. In order to illustrate the presented modeling framework, a case study was carried out in a planted pine forest (Pinus halepensis Mill.) located in south-western Valencia province (Spain). The optimized scenario increased groundwater recharge. This novel modeling framework can be used in the design of a payment for environmental services scheme in which water beneficiaries could contribute to fund and promote efficient forest management operations.

[ES] Se determinó el consumo hídrico de especies forrajeras con la huella hídrica y las funciones de producción respecto al agua para los cultivos de avena forrajera (Avena sativa L.) y raigrás (Lolium perenne), teniendo en cuenta la evaluación de la energía presente en la atmósfera en la región. Se generó un gradiente de humedades según Hanks et al., (1976), para obtener las respuestas. Se llevaron a cabo 15 experimentos para generar el consumo hídrico, la huella hídrica, la producción de biomasa y la productividad hídrica normalizada (WP*). Se consideraron nuevas investigaciones sobre uso de agua, Steduto et al., (2007) implementadas por el modelo AquaCrop (FAO) para la determinación de la biomasa y la producción agrícola a partir del agua para especies herbáceas. El trabajo se desarrolló en el C.I. Tibaitatá, Corpoica (Colombia) (4°42¿N; 74°12¿W), Bogotá, a 2543 msnm. Para avena forajera se encontró una función de producción de segundo orden que define su huella hídrica en forma variable con un punto óptimo de 390 mm para una producción de 22 t ha-1 y una WP* de 18,97 g m-2, mientras que para raigrás una línea recta con un punto máximo de 410 mm y una producción de 10 t ha-1, alcanzando una WP* de 18,08 g m-2 de siembra a primer corte y de 14,66 para los cortes posteriores. Se obtuvieron las curvas del cultivo Kc, Kcb, y Ke de sus respectivos ciclos productivos, con puntos máximos de Kcb de 1,1 para raigrás, y 1,14 para avena forrajera., [EN] Water consumption of forage species with the water footprint and production functions to water for crops of forage oats (Avena sativa L.) and ryegrass (Lolium perenne) was determined, taking into account the evaluation of the energy in the atmosphere in the region. Moisture gradient as Hanks et al., (1976) was generated, to obtain the answers. It took just 15 experiments to generate water consumption, water footprint, biomass production and water productivity standard (WP*). New research on water use, Steduto et al., (2007) implemented by the model AquaCrop (FAO) for the determination of biomass and agricultural production from water in herbaceous species were considered. The work was developed in the C. I. Tibaitatá, Corpoica (Colombia) (4°42¿N, 74° 12¿W), Bogotá, 2543 meters. To forage oats production function that defines second-order its water footprint variably with an optimum of 390 mm for a production of 22 t.ha-1 and WP* of 18.97 g.m-2 was found, while ryegrass that a line with a peak of 410 mm and an output line 10 t.ha-1, reaching a WP* 18.08 gm-2 of seed and a first cut for subsequent cuts 14.66. Crop Kc curves, Kcb were obtained and Ke of their production cycles, with peaks of 1.1 Kcb for ryegrass and forage oats to 1.18.

[EN] This article is an approach to the spatial configuration influence of the irrigated zone on the unit cost (€/ha) of irrigation network construction. The layout design of the all pipeline network case studies was made using the algorithm by García and Guillem (2004), based on graph theory. This algorithm does not use the designer experience, thus producing homogeneous results. Layouts were sized using the modified economic series method (Arviza, 1991)., [ES] El presente artículo pretende acercarnos al estudio de la influencia que tiene la configuración espacial de la zona reegable sobre el coste unitario (€/ha) de implantación de una red de riego a presión para riego. El trazado en planta de las redes analizadas en este trabajo se realiza utilizando el algoritmo de García y Guillem (2004), basado en teoría de grafos que elimina la habilidad o experiencia del proyectista generando resultados homogéneos. Estos trazados se dimensionan utilizando el método de la serie económica modificada (Arviza, 1991)