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International audience; The regeneration of riparian shrub and tree species in the Salicaceae family is frequently impaired by human activities. Salicaceae forest restoration has been traditionally approached from a terrestrial perspective that emphasized planting. More recently, floodplain restoration activities have embraced an aquatic perspective, inspired by the emerging philosophy of environmental flows for river management. However, riparian Salicaceae species occur at the interface of both terrestrial and aquatic ecosystems along watercourses, and their regeneration depends on a complex interaction of hydrologic and geomorphic processes that have shaped key life-cycle requirements for seedling establishment. Ultimately, restoration needs to integrate these concepts to succeed. However, the literature reporting restoration actions on Salicaceae regeneration is scattered, and a specific theoretical framework is still missing. We reviewed 105 published experiences in restoration of Salicaceae forests, including 91 projects in 10 world regions throughout their range across the Northern Hemisphere, to construct a decision tree to inform restoration planning through explicit links between the well-studied biophysical requirements of Salicaceae regeneration and 17 specific restoration actions. Planting (in 55% of the projects), land contouring (30%), competing vegetation removal (30%), site selection (26%), and irrigation (24%) were the most common restoration actions. Environmental flows, including induced large pulse flows (8%), managed recessions (13%), base flows (7%) and flow sequencing (11%) were effective restoration actions in less populated areas. With alternative, innovative and feasible approaches that also incorporate human needs, it could be possible to restore S alicaceae riparian forests to better fit their new hydrologic and fluvial geomorphic situation.

International audience; Black poplar (Populus nigra L.) pioneer trees are riparian ecosystem engineers which modify their fluvial habitat, e.g., by enhancing sediment accumulation. The engineer effect implies that young individuals are successful in establishment. However, the specific above- and below-ground responses of young poplars to hydrogeomorphological constraints that lead to establishment remain poorly understood. Based on the hypothesis of an eco-evolutionary feedback between woody riparian species and fluvial geomorphology, we performed a semi-controlled ex situ experiment to exhaustively quantify response traits of poplar cuttings to simulated hydrogeomorphological constraints. A completely randomized experimental design was employed with cuttings (n=128) and treatments (i.e., the simulated constraints: sediment burial, drag force exerted by floods, their combination, and control). Two partial harvests were performed to evaluate the development of the plants (especially, below ground). At the end of the first growing season, a final harvest was performed in which plants were divided into two groups of equal number (n=48 each). A whole-plant extraction was carried out for the first half of plants; an uprooting test was performed with the second half of plants. Above- and below-ground morphological traits were measured manually and from image analysis for both groups. Biomechanical and anatomical traits were also recorded to characterize the plasticity of this species and to dissociate the specific and more relevant responses to each type of constraint. The results from this research will improve our understanding of riparian ecosystem functioning and specifically of the role of this foundation woody pioneer species within active floodplain rivers.

Riparian ecosystems are highly dynamic and are subject to hydrogeomorphological processes. In Europe, the lower Allier River (France) is one of the last remaining meandering rivers with laterally dynamic sections. For this study, we developed an original method to analyse the vegetation assemblages and succession processes. The analysis includes both spatial and temporal evolution in order to evaluate the shifting paradigm of habitat mosaic at the study site over a 60-year period. On the long-term, floods with low recurrence intervals tend to be important for small scale habitat changes, whereas major flood events lead to major habitat changes. Flood events did not change the overall habitat composition of the active tract but their spatial distribution. The lack of major hydrogeomorphological disturbance observed during the last two decades, however, led to a higher stability of floodplain ecotopes.

Riparian ecosystems are highly dynamic ecosystems subjected to hydrogeomorphological processes. Their geomorphological, sedimentological and hydrological heterogeneity makes them one of the richest ecosystems in terms of species diversity. In addition, riparian zones also provide numerous ecosystem functions and services to society. In the European context, the lower river Allier (France) is one of the last remaining rivers with laterally dynamic sections. Its historical evaluation has shown repeated river bed displacements during the last century. Spatio-temporal processes on a highly mobile river section of the lower river Allier have been studied analysing the mosaic of vegetation types and successional phases as well as physical habitat parameters. Understanding riparian ecosystem functioning and evolution in natural or nearly natural systems is essential for river restoration practices in highly degraded rivers. This understanding may lead to the establishment of better sustainable river rehabilitation targets that consider societal needs and natural processes., Les écosystèmes riverains sont des écosystèmes dynamiques soumis aux processus hydrogéomorphologiques avec une forte hétérogénéité géomorphologique, sédimentologique et hydrologique et de nombreux services écosystémiques rendus à la société. Ils font partie des écosystèmes les plus riches en termes de diversité des espèces. Dans le contexte européen, la rivière Allier aval est une des dernières rivières avec des sections à forte mobilité latérale. L'analyse historique a démontré cette forte mobilité latérale des chenaux durant le siècle dernier. Des processus spatio-temporels d'une section de rivière très mobile ont été étudiés à travers l'analyse de la mosaïque des types de végétation, les phases de succession, ainsi que les paramètres physiques des habitats. Comprendre le fonctionnement et l'évolution des écosystèmes riverains dans des systèmes naturels ou proche de l'état naturel est essentiel pour la restauration des cours d'eau très dégradées, afin de permettre la mise en place de stratégies de réhabilitions durables qui considèrent les besoins de la société et les processus naturels.

International audience; Populations of the riparian pioneer species Populus nigra L. which establish on alluvial bars within river channelsmodulate sediment dynamics and fluvial landforms. Dense cohorts of P. nigra have colonized gravel point bars along the channelizedRiver Garonne, France, during the last 20 years and have enhanced the vertical, lateral and longitudinal development of thebars. For this period, the geomorphic characteristics of two wooded point bars on this laterally stable river are closely linked tothe spatial distribution and intensity of establishment and resistance of different cohorts of P. nigra. Furthermore, P. nigra colonizationdynamics were controlled by engineer effects of this same species. This relationship is illustrated by a significant correlation betweenkey geomorphic and biological variables measured in situ and characterized with a set of four aerial photographs taken between2000 and 2010. The development of wooded point bars, which are discrete biogeomorphic units, over the studied period, appearto result from a specific biogeomorphic positive feedback of matter aggregation and vegetation establishment related to sedimenttrapping and stabilization by pioneer engineer plants.We propose a conceptual model of biogeomorphic unit construction for channelized,lateral stable rivers.We consider the resultant biogeomorphic units as functional from an ecological point of view because P.nigra enhances at the cohort scale (i) its own inherent capacity to resist hydrogeomorphic disturbances, and (ii) its resilience capacityas a result of successful colonization, especially downstream of mature poplar stands.

National audience

Biotic and abiotic interactions between the riparian zone and the river determine relevant hydrological processes and exert control over riparian and bordering upland vegetation types. Vegetation growth and development are mainly controlled by water availability on semi-arid regions, where a moisture gradient determines the transition between the densely vegetated riparian zone and the semi-arid upland. To reproduce this spatial distribution, a mathematical model named RibAV is presented. Its conceptualization is based on the main ecohydrological modelling approaches and field expertise. The implementation of RibAV that is proposed in this paper allows the simulation of the distribution of three plant functional types [herbaceous riparian vegetation (HRV), woody riparian vegetation (WRV) and terrestrial vegetation (TV)] within the riparian zone. An evapotranspiration index (Eidx) obtained through RibAV is used as a criterion for plant absence/presence prediction. Two permanent river reaches of semi-arid Mediterranean basins, the Terde reach (Mijares River, Spain) and the Lorcha reach (Serpis River, Spain), have been selected as case studies for the calibration and validation of the model, respectively. Several criteria based on the confusion matrix were used to analyse the efficiency of RibAV on the prediction of plant distribution. The satisfactory performance of the model establishing the distribution of the riparian vegetation types and the limit between this zone and the bordering upland are demonstrated in this paper; the strength of the Eidx to classify plant functional types in riparian semi-arid environments is additionally proven, The authors would like to thank the Spanish Ministry of Environment and the Spanish Ministry of Economy and Competitiveness for their financial support through the research projects RIBERA (21.812-061/8511) and SCARCE (Consolider-Ingenio 2010 CSD2009-00065), respectively. In addition, the authors would like to thank the Hydrological Studies Centre (CEH-CEDEX), the Jucar River Basin Authority and the Spanish National Meteorological Agency (AEMET) for supplying the hydrological data, the aerial photographs and the meteorological data, respectively.

Riparian ecosystems are required to be preserved to achieve a good ecological status. The Water Framework Directive (2000/60/EC) specifically supports the assessment of new management tools that allow the European Member States to achieve good ecological status of river-related ecosystems. Within several approaches, a dynamic riparian vegetation distributed model (CASiMiR-vegetation), with a time step of 1 year, has been selected as a useful first-step tool to achieve the Water Framework Directive requirements. The model has been implemented into three river reaches with different climatic and hydrologic settings, located in three European countries. Common bases were established in the model setup. The model was calibrated independently in the Kleblach reach (Drau River, Austria), the Ribeira reach (Odelouca River, Portugal), and the Terde reach (Mijares River, Spain) with simulation periods of 8, 11 and 41 years, respectively. The parameter values and the results were comparable between the different countries. The calibration performance achieved high correctly classified instances (60%). Additionally, weighted kappa values ranged from 0·52 to 0·66 in distinguishing riparian succession phases. The model behaved similarly in the validation, even offering better results in most cases. This work demonstrates the applicability of this model in the simulation of the riparian vegetation dynamic distribution over a wide range of environments. As it performs in a robust manner and with good results in reaches with different hydrological characteristics, the model could be also applied to analyse different hydrological scenarios or to predict changes after restoration measures within a reach. Copyright © 2012 John Wiley & Sons, Ltd., The Austrian team would like to thank the Lebensministerium (Austrian Ministry of Environment) and Professor Helmut Habersack and his group from the University of Natural Resources and Life Science Vienna for the supply of the hydrological data. The Portuguese team would like to thank Antonio Pinheiro for his supervision of the hydraulic modelling. The hydrological data were supplied by the Portuguese National Hydrologic Resource Information System (SNIRH) and aerial photographs by the Portuguese Geographic Institute (IGP) under the FIGIEE programme. Patricia M. Rodriguez-Gonzalez benefited from a postdoctoral grant from FCT (SFRH/BPD/47140/2008). Antonio Albuquerque was a valuable assistant in field work. The Spanish team would like to thank in addition the Hydrological Studies Centre (CEH-CEDEX), the Jucar River Basin Authority (CHJ) and the Spanish National Geographic Information Centre (CNIG) for supplying the hydrological data and the aerial photographs for the Spanish study site.

Riparian corridors in semi-arid Mediterranean environments are ecosystems of high biodiversity and complexity. However, they are threatened because of high levels of human intervention. River damming and related flow manipulation is considered as one of the most prominent human impacts on riparian corridors. This study combines historical time series information on river flows and their human manipulation, historical aerial images depicting changes in riparian land cover and ground observations of the species - age composition and morphology of the riparian corridor of a Mediterranean river (the Mijares River, Eastern Spain) over the last 60years. In this sense, we explored how to integrate information from a wide variety of data sources, and we extracted a variety of indices and undertook analyses that identified and summarized spatio-temporal changes in riparian structure and in the driving flow processes. Results revealed an increase in the cover and density of woody vegetation and a decrease in bare sediment areas (essential for recruitment of riparian pioneer species), with a synchronous reduction in the complexity of the riparian corridor of the middle reaches of the Mijares River. These vegetation changes have accompanied a decrease in the magnitude and variability of river flows over the last six decades, with higher severity since dam closure. This study illustrates the effectiveness of combining disparate historical data sources and the effectiveness of processing these sources to extract informative metrics that can improve the understanding and management of riparian systems. © 2012 John Wiley & Sons, Ltd., The authors are grateful to Paula De Lamo (who worked in an early version of this study), Carlos Gonzalez-Hidalgo (who gave us access to the MOPREDAS database) and Alicia Garcia-Arias and Oscar Belmar (for their support in the calculation of confusion matrices and in the flow regime analysis, respectively). We also thank Confederacion Hidrografica del Jucar (Spanish Ministry of Agriculture, Food and Environment) and the professors Juan Marco Segura and Javier Paredes for the hydrological data provided to develop this study. TECNOMA S. A. provided logistic support. Finally, we acknowledge the Universitat Politecnica de Valencia for the two grants of the Support Programme for Research and Development 'Programa de Apoyo a la Investigacion y Desarrollo' (PAID 00-10 and 00-11). This study was partially funded by the Spanish Ministry of Economy and Competitiveness with the projects 'Recent environmental changes in fluvial systems: morphological and sedimentological consequences' (CGL2009-14220-C02-02-BTE) and SCARCE (Consolider-Ingenio 2010 CSD2009-00065). The feedback of two anonymous reviewers has been very helpful and is greatly appreciated.

Habitat degradation has reduced the complexity of the Mediterranean streams in Spain and contributed to decreasing the historical range of the endangered Júcar nase, Parachondrostoma arrigonis. This species is endemic to the Júcar River Basin (Spain), and most of its populations live in the Cabriel River, which is divided into two segments by the large Contreras Dam. The main objective of this study was to develop a multivariate habitat suitability model (HSM) for this species that can be used to evaluate environmental flows and water management scenarios for the Cabriel River. We first assessed the fish densities (from 2006 to 2008) and compared the habitat characteristics and variability among eight study sites based on the physical characteristics of hydromorphological units (HMUs) or mesohabitats. The abundance of the Júcar nase then was related to the HMU type, and generalized additive models of fish abundance were developed for the sites for both small and large fish. Both models showed acceptable or good performance (adjusted R 2 of 69.4 for small fish and 72.4 for large fish), and fish abundance was used as an indicator of potential habitat quality ['potential nase habitat' (PNH)] for the Júcar nase. The final step was to apply the HSM to evaluate environmentally friendly flow regimens. Hydraulic simulations were used to estimate the PNH under two flow regimen scenarios and in the actual flow regimen for the regulated study site located below the large dam. This article supports the need for new management actions in the Cabriel River, such as implementation of an environmental flow regimen, and illustrates a procedure for the practical application of habitat selection models at the mesohabitat scale., This study was partially funded by the Spanish Government (Ministerio de Medio Ambiente y Rural y Marino, Confederacion Hidrografica del Jucar) and partly by the Spanish Ministry of Education and Science (POTECOL, CGL2007-66412). We especially thank Matias Peredo and Aina Hernandez for the co-operation in the field work and suggestions on data analysis; we also thank Rafa Casas, Marta Bargay, Pau Lucio, Merce Arenas and the students that cooperated in the field work. Thanks to Colin Custard for the academic review of English. We also acknowledge the comments and suggestions of the reviewers on this paper.

[EN] In the European context, several methodologies have been developed to assess the ecological status and, specifically, the hydromorphological status of running surface waters. Although these methodologies have been widely used, few studies have focused on hydrologically altered water bodies and the factors that may determine their status. In this study, the Serpis River was divided into 16 segments from the Beniarrés dam (40 km from the river mouth) to the sea, all of which are affected by flow regulation, but with different severity. In each segment, an inventory of the flora was conducted, and hydromorphological indices (QBR, Riparian Habitat Quality Index; and IHF, River Habitat Index) were applied. The objectives of the study were (A) to identify relationships between floristic composition and QBR components and (B) between instream habitat characteristics and IHF components as well as (C) to determine the main factors controlling the floristic composition and riparian habitat quality (QBR) and the factors controlling instream habitat characteristics and heterogeneity (IHF). A cluster analysis allowed grouping sites according to their floristic composition and instream habitat characteristics, and non-metric multidimensional scaling (NMDS) was used to ordinate the sites, obtaining the biotic and instream habitat characteristics, as well as the QBR and IHF subindices, which better explained the spatial patterns. Finally, a canonical correspondence analysis (CCA) with predictor variables (geographical, hydrological, geomorphological and human pressures) indicated the main factors controlling the spatial patterns of the floristic composition, instreamhabitat characteristics, riparian habitat quality and instream habitat heterogeneity. A gradient of riparian and instream habitat quality was identified. Our results suggest that physical constraints (presence of a gorge) have protected sites from severe human impacts, resulting in good ecological quality, despite hydrological alteration. This area, where there is geomorphological control, could be potentially reclassified into a different ecotype because regular monitoring could be using incorrect references for index scores, and naturally high scores could be confused with recovery from hydrological alteration or other pressures. The sites with the worst quality were near the river mouth and were characterised by an artificial and highly variable flow regime (related to large autumnal floods and frequent human-induced periods of zero flow). This artificial flow variability as well as the presence of lateral structures in the river channel and geomorphological characteristics were identified as the main factors driving the hydromorphological and floristic pattern in this regulated river., [ES] Diversas metodolog´ıas han sido desarrolladas en el contexto europeo para evaluar el estado ecologico, y espec ´ ´ıficamente el estado hidromorfologico de las aguas superficiales. Aunque ´ estas han sido ampliamente utilizadas, pocos estudios se han centrado en masas de agua hidrologicamente alteradas y en los factores que condicionan su estado. En este ´ estudio, el r´ıo Serpis fue dividido en 16 segmentos desde la presa de Beniarres (a 40 km de la desembocadura) hasta el mar, todos ´ ellos afectados por la regulacion de caudales con distinta severidad. En cada segmento se realiz ´ o un inventario flor ´ ´ıstico y se aplicaron ´ındices hidromorfologicos (QBR, Calidad del Bosque de Ribera, e IHF, ´ ´Indice de Habitat Fluvial). Los ´ objetivos del estudio fueron (A) identificar relaciones entre la composicion flor ´ ´ıstica y los componentes del QBR, (B) entre las caracter´ısticas del habitat fluvial y los componentes del IHF, (C) determinar los principales fa ´ ctores que controlan la composicion flor ´ ´ıstica y la calidad del habitat ripario (QBR), y las caracter ´ ´ısticas del habitat fluvial y su heterogeneidad ´ (IHF). Un cluster permitio agrupar los puntos de muestreo seg ´ un su composici ´ on flor ´ ´ıstica y las caracter´ısticas del habitat fluvial, y un escalado multidimensional no-m ´ etrico (NMDS) fue usado para ordenar los puntos, obteniendo las ´ variables bioticas y caracter ´ ´ısticas del habitat y los subindices del QBR e IHF, respectivamente, que explicaban m ´ ejor los patrones espaciales. Finalmente, un analisis de correspondencias can ´ onicas (CCA) con variables predictoras (geogr ´ aficas, ´ hidrologicas, geomorfol ´ ogicas y presiones humanas) indic ´ o los principales factores que controlan los patrones espaciales de ´ la composicion flor ´ ´ıstica, las caracter´ısticas del habitat fluvial, la calidad del h ´ abitat ripario y la heterogeneidad del h ´ abitat ´ fluvial. Se identifico un gradiente de calidad del h ´ abitat ripario y fluvial. Los resultados sugieren que las limitaciones f ´ ´ısicas (presencia de un can˜on) han protegido a los tramos de impactos humanos severos, resultand ´ o en una buena calidad ecologica ´ a pesar de la alteracion hidrol ´ ogica. Esta zona podr ´ ´ıa potencialmente ser reclasificada en un ecotipo diferente, ya que un monitoreo regular podr´ıa estar usando referencias incorrectas para los ´ındices y sus altas puntuaciones naturales se podr´ıan estar confundiendo con una recuperacion de la alteraci ´ on hidrol ´ ogica o de otras presiones. Los puntos de muestreo con peor ´ calidad estuvieron cerca de la desembocadura y tuvieron un regimen de caudales alterado y muy variable. Esta variabilidad ´ artificial del caudal, junto con la presencia de estructuras laterales en el cauce y las caracter´ısticas geomorfologicas fueron ´ identificadas como los principales factores determinantes del patron hidromorfol ´ ogico y flor ´ ´ıstico en este r´ıo regulado., The authors would like to thank the reviewers for their comments and suggestions on an earlier version of this manuscript and the Jucar River Basin Authority (CHJ) for supplying public hydrological data. This study was supported by the Spanish Ministry of Environment and Rural and Marine Affairs (RIBERA Project) and the Ministry of Education and Science (projects TETIS-2, CGL2005-06219; POTECOL, CGL2007-66412; RIPFLOW, CGL2008-03076-E/BTE). We would also like to thank the CEIC Alfons El Vell (Gandia) for partially funding this research with a grant to Virginia Garofano G ´ omez. The translation of this paper was funded by the Universitat Politecnica de Val ` encia, Spain.

In the European context, several methodologies have been developed to assess the ecological status and, specifically, the hydromorphological status of running surface waters. Although these methodologies have been widely used, few studies have focused on hydrologically altered water bodies and the factors that may determine their status. In this study, the Serpis River was divided into 16 segments from the Beniarr'es dam (40 km from the river mouth) to the sea, all of which are affected by flow regulation, but with different severity. In each segment, an inventory of the flora was conducted, and hydromorphological indices (QBR, Riparian Habitat Quality Index; and IHF, River Habitat Index) were applied. The objectives of the study were (A) to identify relationships between floristic composition and QBR components and (B) between instream habitat characteristics and IHF components as well as (C) to determine the main factors controlling the floristic composition and riparian habitat quality (QBR) and the factors controlling instream habitat characteristics and heterogeneity (IHF). A cluster analysis allowed grouping sites according to their floristic composition and instream habitat characteristics, and non-metric multidimensional scaling (NMDS) was used to ordinate the sites, obtaining the biotic and instream habitat characteristics, as well as the QBR and IHF subindices, which better explained the spatial patterns. Finally, a canonical correspondence analysis (CCA) with predictor variables (geographical, hydrological, geomorphological and human pressures) indicated the main factors controlling the spatial patterns of the floristic composition, instreamhabitat characteristics, riparian habitat quality and instream habitat heterogeneity. A gradient of riparian and instream habitat quality was identified. Our results suggest that physical constraints (presence of a gorge) have protected sites from severe human impacts, resulting in good ecological quality, despite hydrological alteration. This area, where there is geomorphological control, could be potentially reclassified into a different ecotype because regular monitoring could be using incorrect references for index scores, and naturally high scores could be confused with recovery from hydrological alteration or other pressures. The sites with the worst quality were near the river mouth and were characterised by an artificial and highly variable flow regime (related to large autumnal floods and frequent human-induced periods of zero flow). This artificial flow variability as well as the presence of lateral structures in the river channel and geomorphological characteristics were identified as the main factors driving the hydromorphological and floristic pattern in this regulated river. Diversas metodologías han sido desarrolladas en el contexto europeo para evaluar el estado ecológico, y específicamente el estado hidromorfológico de las aguas superficiales. Aunque éstas han sido ampliamente utilizadas, pocos estudios se han centrado en masas de agua hidrológicamente alteradas y en los factores que condicionan su estado. En este estudio, el río Serpis fue dividido en 16 segmentos desde la presa de Beniarrés (a 40 km de la desembocadura) hasta el mar, todos ellos afectados por la regulación de caudales con distinta severidad. En cada segmento se realizó un inventario florístico y se aplicaron índices hidromorfológicos (QBR, Calidad del Bosque de Ribera, e IHF, Índice de Hábitat Fluvial). Los objetivos del estudio fueron (A) identificar relaciones entre la composición florística y los componentes del QBR, (B) entre las caracteríısticas del hábitat fluvial y los componentes del IHF, (C) determinar los principales factores que controlan la composición florística y la calidad del hábitat ripario (QBR), y las características del hábitat fluvial y su heterogeneidad (IHF). Un cluster permitió agrupar los puntos de muestreo según su composición florística y las características del hábitat fluvial, y un escalado multidimensional no-métrico (NMDS) fue usado para ordenar los puntos, obteniendo las variables bióticas y características del hábitat y los subindices del QBR e IHF, respectivamente, que explicaban mejor los patrones espaciales. Finalmente, un análisis de correspondencias canónicas (CCA) con variables predictoras (geográficas, hidrológicas, geomorfológicas y presiones humanas) indicó los principales factores que controlan los patrones espaciales de la composición florística, las características del hábitat fluvial, la calidad del hábitat ripario y la heterogeneidad del hábitat fluvial. Se identificó un gradiente de calidad del hábitat ripario y fluvial. Los resultados sugieren que las limitaciones físicas (presencia de un cañón) han protegido a los tramos de impactos humanos severos, resultando en una buena calidad ecológica a pesar de la alteración hidrológica. Esta zona podría potencialmente ser reclasificada en un ecotipo diferente, ya que un monitoreo regular podría estar usando referencias incorrectas para los índices y sus altas puntuaciones naturales se podrían estar confundiendo con una recuperación de la alteración hidrológica o de otras presiones. Los puntos de muestreo con peor calidad estuvieron cerca de la desembocadura y tuvieron un régimen de caudales alterado y muy variable. Esta variabilidad artificial del caudal, junto con la presencia de estructuras laterales en el cauce y las características geomorfológicas fueron identificadas como los principales factores determinantes del patrón hidromorfológico y florístico en este río regulado.

The relationship between flows and riparian vegetation has been described in the Mijares River, one of the most important rivers of the Júcar River basin (Eastern Spain). The three study sites have a flow regime which is regulated by a large dam and several hydropower plants. A hydraulic simulation was done in each site, and the time series of flow and water elevation were calculated for the period 1990-2007. The discharge-elevation curves were calculated in channel cross-sections, based on field data (low flows) and hydraulic simulation of large floods (50, 100 & 500 years intervals).