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[ES] En los últimos años la Ecohidrología ha cubierto la necesidad de comprender como los procesos ecológicos regulan e interactúan dentro del ciclo hidrológico, permitiendo adoptar alternativas de gestión más variadas y versátiles con el fin de mejorar la sostenibilidad ambiental. Nuestra área de estudio se ubica en la cuenca del Carraixet en donde se ha calibrado el modelo ecohidrológico TETIS, primero se han estimado los mapas de parámetros que fueron calculados a partir del modelo de elevación digital, usos de suelo, edafología, geomorfología y litología de la cuenca. Asimismo, para la estimación inicial de los parámetros efectivos de vegetación se tomaron como referencia los valores obtenidos en la investigación de Sanchis et al. (2019) llamada "Managing low productive forests at catchment scale: Considering water, biomass and fire risk to achieve economic feasibility". Luego se realizó la calibración del modelo TETIS mediante cuatro configuraciones: a) Monobjetivo Temporal, b) Multiobjetivo temporal, c) Monobjetivo espacio - temporal y d) Multiobjetivo espacio - Temporal, en las calibraciones monobjetivo se empleó el algoritmo de SCE-UA para optimización del modelo. Sin embargo, en la calibración multiobjetivo se utilizó el algoritmo de MOSCEM-UA y la metodología de las funciones empíricas ortogonales para la optimización del modelo. Finalmente, se encontró que la calibración multiobjetivo espacio - temporal (variables de estado: caudal y humedad del suelo) es la que representaba adecuadamente el comportamiento de los caudales y dinámica de la vegetación en la cuenca. En el análisis de escenarios de gestión forestal se realizó sobre 4 usos forestales que abarcaban gran parte del área de la cuenca. Asimismo, se estableció un escenario de control en donde el factor de cobertura fue igual 0.85 (85% de la densidad de cubierta) y se asumió talas de 20%, 30%, 40% y 50%. Los resultados mostraron que el Índice de área foliar (LAI), la humedad del suelo en la capa prof, [EN] In recent years Ecohydrology has covered the need to understand how ecological processes regulate and interact within the hydrological cycle, allowing the adoption of more varied and versatile management alternatives to improve environmental sustainability. Our area of study is in the Carraixet basin where the TETIS eco-hydrological model has been calibrated. First, the parameter maps have been estimated from the digital elevation model, land use, pedology, geomorphology and lithology of the basin. Likewise, for the initial estimation of the effective vegetation parameters, the values obtained in the research of Sanchis et al. (2019) called "Managing low productive forests at catchment scale: Considering water, biomass and fire risk to achieve economic feasibility" were taken as reference. Then, the calibration of the TETIS model was carried out using four configurations: a) Mono-objective Temporal, b) Multi-objective Temporal, c) Mono-objective Space-Time and d) Multi-objective Space-Time. The SCE-UA algorithm was used in the mono-objective calibrations to optimize the model. However, in the multiobjective calibration the MOSCEM-UA algorithm and the methodology of the orthogonal empirical functions were used for the optimization of the model. Finally, it was found that the space-time multiobjective calibration (state variables: flow and soil moisture) is the one that adequately represented the behavior of the flows and dynamics of the vegetation in the basin. The analysis of forest management scenarios was carried out on 4 forest uses that covered a large part of the area of the basin. Likewise, a control scenario was established where the coverage factor was equal to 0.85 (85% of the cover density) and assumed felling of 20%, 30%, 40% and 50%. The results showed that the Leaf Area Index (LAI), deep soil moisture and direct evaporation increased as logging in forest management intensified. However, variables such as transpiration and topsoil moisture showed gr

[EN] Usually, megacities expand without proper planning in a context of demographic growth and are increasingly dependent on the natural resources related to the occupied area. This is a major challenge for the sustainable management of these territories, justifying the need for a better knowledge of land use/land cover (LULC) distribution and characteristics to observe spatial anthropogenic dynamics. In this study, the Bogota river basin and the Bogota megacity were analyzed as a case study. The main objective of this work was to analyze the historical LULC dynamics from 1985 to 2014. Reliable forecasting scenarios were developed using the Land Change Modeler to support sustainable management and planning. Results show an expansion of the Bogota megacity toward the Northeast and an increase of urban areas within the basin. These changes implied a loss of 58% of forest surface, a strategic ecosystem, from 1985 to 2014. This dynamic is expected to continue, with a 50% increase of urban areas between 2012 to 2050, thus the megacity and neighbor cities potentially become an "urban continuum". A replacement of crop and pasture lands near the city is expected, even though Bogota lands are among the best agricultural lands in the Andean region of Colombia.

The Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishes a framework for Community action in the field of water policy. This Directive defines Status of a Body of Surface Water, as the poorer of its ecological and chemical status. The ecological status is determined by use of biological, physicochemical and hydromorphologic indicators. Both biological and physicochemical indicators protocols have been legally established. Thus, this constitutes a framework for characterizing the different Spanish River Basins in a unified technical language. However, the protocol for the hydromorphological indicators titled as Hydromorphological Characterization Protocol of Body of Surface Water of the Rivers Category (hereinafter, Protocol) is still being developed by the Ministry of Agriculture and Fisheries, Food and Environment (MAPAMA). To the current date, the approval of the definitive version appears imminent. One of the main points in which the Protocol is based, is the structure and composition of riparian vegetation. We would expect the hydrological regime to have an effect on the above mentioned variables. In order to assess this, I have used a dynamic distribution model of riparian vegetation called Riparian Vegetation Dynamic Model (hereinafter, RVDM), developed by the Institute of Water and Environmental Engineering (IIAMA) of the Polytechnic University of Valencia (García-Arias and Francés, 2016). In this study, I have assessed the level of vulnerability of riparian vegetation in relation to the different management regimes of water resources. I have evaluated as well the suitability of the minimum requirements that are currently being applied for the maintenance of the water sources on the medium and long term. The main goal has been to improve the capacity of water managers to take preventive and palliative measures of the possible impacts on the ecological state of the riparian areas as a whole. The purposes of this Mas, La Directiva 2000/60/CE del Parlamento Europeo y del Consejo, de 23 de octubre de 2000 (en adelante DMA), que establece un marco comunitario de actuación en el ámbito de la política de aguas, define el Estado de las Masas de Agua Superficial como el peor estado entre el estado ecológico y el químico. Para la determinación del estado ecológico se utilizan indicadores biológicos, físico-químicos e hidromorfológicos. En la actualidad, para los dos primeros tipos de indicadores se disponen de protocolos que permiten unificar criterios de actuación en las diferentes cuencas de los ríos españoles, mientras que el protocolo para los indicadores hidromorfológicos titulado como Protocolo de Caracterización Hidromorfológica de Masas de Agua de la Categoría Ríos (en adelante, Protocolo), aún está siendo desarrollado por el Ministerio de Agricultura y Pesca, Alimentación y Medio Ambiente (MAPAMA), estando muy cercana la aprobación de la versión definitiva. Uno de los pilares sobre los que se asienta el Protocolo, es la estructura y composición de la vegetación de ribera. Para conocer la evolución de dichas variables y la influencia del régimen hidrológico sobre ellas, se pretende utilizar un modelo de distribución dinámica de la vegetación de ribera denominado Riparian Vegetation Dynamic Model (en adelante, RVDM), desarrollado por el Instituto de Ingeniería del Agua y Medio Ambiente (IIAMA) de la Universitat Politècnica de Valencia (García-Arias y Francés, 2016). En este trabajo, se tiene la intención de comprobar la vulnerabilidad de la vegetación riparia frente a la gestión de los recursos hídricos y establecer si los requerimientos mínimos que actualmente se están aplicando son suficientes para su correcto mantenimiento a medio y a largo plazo, con el objetivo de mejorar la capacidad de los gestores del agua para adoptar medidas preventivas y paliativas de los posibles impactos sobre el estado ecológico de las zonas de ribera en su conjunto. El presente Trabajo Fin de Máster, [CA] La Directiva Marc de l'Aigua (DMA, 2000/60/CE) del Parlament Europeu i del Consell, que estableix un marc comunitari d'actuació en l'àmbit de la política d'aigües, defineix l'Estat de les Masses d'Aigua Superficial com el pitjor estat entre l'estat ecològic i el químic. Per a la determinació de l'estat ecològic s'utilitzen indicadors biològics, físicoquímics i hidromorfològics. En l'actualitat, existeixen protocols definits per als indicadors biològics i físicoquímics que permeten unificar criteris d'actuació en les diferents conques dels rius espanyols, però no per als indicadors hidromorfològics. Per a esmenar aquest dèficit metodològic i determinar de forma coherent de l'estat ecològic, s'està desenvolupant en l'actualitat el Protocol de Caracterització Hidromorfològica de Masses d'Aigua Superficial de la Categoria Rius (Ministeri Agricultura i Pesca, Alimentació i Medi ambient (MAPAMA), 2017), que prompte n’aprovarà la versió definitiva. Una de les parts essencials de l'avaluació hidromorfològica és l'estructura de la zona de ribera, és de sobres coneguda la importància de la interacció del bosc de ribera amb la hidrologia de la zona de ribera. Per a conèixer l'evolució d'aquestes variables i la influència del règim hidrològic sobre aquestes, s'utilitza un model de distribució dinàmica de la vegetació de ribera denominat Riparian Vegetation Dynamic Model (RVDM) (García-Arias i Francés, 2016). L'objectiu principal del present Treball Fi de Máster és la modelització ecològica d'àrees ripàries pertanyents a l'àmbit de la Demarcació Hidrogràfica del Xúquer (CHJ) mitjançant l'aplicació del nou Protocol de Caracterització Hidromorfològica i la modelització de la dinàmica del bosc de ribera mitjançant el model RVDM, de manera que es donen a conèixer les potencialitats d'aquestes dues noves eines. Per a açò s'ha realitzat una recopilació de la informació necessària, una anàlisi d'ambdues eines, i la seua posterior implementació i aplicació en dos trams d'estudis pi

"This is the peer reviewed version of the following article: Muñoz-Mas, R., V. Garófano-Gómez, I. Andrés-Doménech, D. Corenblit, G. Egger, F. Francés, M.T. Ferreira, et al. 2017. ¿Exploring the Key Drivers of Riparian Woodland Successional Pathways across Three European River Reaches.¿ Ecohydrology 10 (8). Wiley: e1888. doi:10.1002/eco.1888, which has been published in final form at https://doi.org/10.1002/eco.1888. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.", [EN] Climate change and river regulation are negatively impacting riparian vegetation. To evaluate these impacts, process-based models are preferred over data-driven approaches. However, they require extensive knowledge about ecohydrological processes. To facilitate the implementation of such process-based models, the key drivers of riparian woodland successional pathways across three river reaches, in Austria, Portugal, and Spain, were explored, employing two complementary approaches. The principal component analyses highlighted the importance of the physical gradients determining the placement of the succession phases within the riparian and floodplain zones. The generalized additive models revealed that the initial and pioneer succession phases, characteristic of the colonization stage, appeared in areas highly morphodynamic, close in height and distance to the water table, and with coarse substrate, whereas elder phases within the transitional and mature stages showed incremental differences, occupying less dynamic areas with finer substrate. The Austrian site fitted well the current successional theory (elder phases appearing sequentially further up and distant), but at the Portuguese site, the tolerance of the riparian species to drought and flash flood events governed their placement. Finally, at the Spanish site, the patchy distribution of the elder phases was the remnants of formative events that reshaped the river channel. These results highlight the complex relationships between flow regime, channel morphology, and riparian vegetation. The use of succession phases, which rely on the sequential evolution of riparian vegetation as a response to different drivers, may be potentially better reproducible, within numerical process-based models, and transferable to other geographical regions.

[EN] The riparian vegetation dynamic model (RVDM) is an ecohydrological model aimed to study the vegetation dynamics in riparian areas that represents an upgrade with respect to previous tools in the way of understanding the riparian dynamics. Important novelties are proposed by this tool, including a high temporal resolution (daily time step), a proposal of a new plant classification approach useful for research and management (successional plant functional types), good representation of the key processes that determine the vegetation dynamics in riparian areas (drought and flood impacts, recruitment, growth, succession and competition), an easy implementation and feasible inclusion of river morphodynamics in the model implementation (including different daily elevation and soil maps in the inputs). The model implementation in a Mediterranean semi-arid study site resulted satisfactorily (cell by cell calibration accuracy >= 65% and cell by cell validation accuracy between 40% and 60%), demonstrating the great potential of this approach for future research and management applications. Although 36 parameters are included in the model conceptualization, the global sensitivity analysis demonstrated that only eight types of parameters are actually influent. These parameters are as follows: minimum time since mixed for transition to terrestrial, root depths, transpiration factors, critical shear stress of early stages, minimum biomass required to allow succession, germination minimum capillary water content in the upper soil, effective depth considered for evaporation from bare soil and coverage of pioneers. Riparian vegetation dynamic model will be a useful tool for gaining a better understanding of the riparian plants behaviour under different ecohydrological conditions. Copyright (C) 2015 John Wiley & Sons, Ltd.

[EN] The riparian areas can be understood as those areas adjacent or very close to the river channels that are environmentally influenced by this proximity and, in consequence, that are frequently subjected to periodic flooding. The riverbank is an ecosystem itself that has great ecological value. It acts as a transition zone between land and water areas and as a corridor across different regions. As riparian areas are located beside the river water, their soils are frequently very productive. The vegetation in these areas is very productive and favours a great density and diversity of wild life. It has an important role in the ecosystem's capacity for other different functions as the nutrients balance, the water temperature regulation by shadowing, the banks stabilization, etc. In consequence, the riparian vegetation is necessary for the correct balance in the fluvial ecosystem. As this vegetation conditions the hydrology of the river system, the hydrological regime of the river determines the development, the distribution and the diversity of this vegetation. In fact, the presence and wellbeing of the vegetation in semiarid riparian environments is mainly conditioned to the floods frequency and magnitude, to the water availability in the unsaturated upper soil and to the water table accessibility. The aim of the present thesis is to develop and to implement a new ecohydrological dynamic model that predicts the vegetation on the riparian zones of a river reach by including new processes or by reconsidering the definition of those already included in the models taken as reference. In addition, it is pursued to demonstrate the utility of the new model by analysing the dynamic response of the vegetation under different global change scenarios. A background review has been intensively addressed to obtain the required expert knowledge needed to face the proposal of a new methodology for the analysis of the spatial and temporal distribution of the vegetation in the ripar, [ES] Las riberas pueden entenderse como aquellas áreas adyacentes o muy próximas a los cauces fluviales, con inundaciones periódicas, que se ven ambientalmente influidas de forma distintiva por esta proximidad. La ribera es un ecosistema en sí mismo que tiene un gran valor ecológico por constituir una zona de transición entre las zonas terrestre y acuática y un corredor a través de diferentes regiones. Su cercanía al agua, sus suelos tradicionalmente fértiles y su vegetación característica, hacen de estos ecosistemas entornos favorables para una gran densidad y diversidad de vida salvaje. La vegetación de ribera tiene un papel importante en la capacidad del ecosistema para diferentes funciones como son el balance de nutrientes, la regulación de la temperatura de las aguas por efecto del sombreo, la estabilización de las márgenes del río, etc., y por tanto es necesaria para un equilibrio adecuado del ecosistema fluvial. Pero no solo la vegetación de ribera tiene influencia sobre la hidrología del cauce; el desarrollo, la distribución o la diversidad de esta vegetación vienen determinados por el régimen hidrológico del mismo. De hecho, en entornos semiáridos, no solo la frecuencia e intensidad de las avenidas, sino también la cantidad de agua capilar disponible en la zona superficial del suelo, así como la accesibilidad al nivel freático, condicionan tanto la presencia como el bienestar de la vegetación. El objetivo fundamental de esta tesis doctoral es el desarrollo e implementación de un modelo ecohidrológico dinámico, de distribución espacio-temporal de la vegetación de ribera a escala de tramo que, incluyendo nuevos procesos o replanteando la definición de los ya incluidos en los modelos de referencia, mejore los resultados que pueden obtenerse con los modelos actualmente disponibles. Asimismo, se pretende demostrar la utilidad del nuevo modelo mediante el análisis de la respuesta dinámica de la vegetación de ribera a escala de tramo frente a diferentes escenarios, [CA] Les riberes poden entendre's com aquelles àrees adjacents o molt pròximes als llits fluvials, amb inundacions periòdiques, que es veuen ambientalment influïdes de forma distintiva per esta proximitat. La ribera és un ecosistema en si mateix que té un gran valor ecològic per constituir una zona de transició entre les zones terrestre i aquàtica i un corredor a través de diferents regions. La seua proximitat a l'aigua, els seus sòls tradicionalment fèrtils i la seua vegetació característica, fan d'estos ecosistemes entorns favorables per a una gran densitat i diversitat de vida salvatge. La vegetació de ribera té un paper important en la capacitat de l'ecosistema per a diferents funcions com són el balanç de nutrients, la regulació de la temperatura de les aigües per efecte de l'ombrege, l'estabilització dels marges del riu, etc., i per tant és necessària per a un equilibri adequat de l'ecosistema fluvial. Però no sols la vegetació de ribera té influència sobre la hidrologia del llit; el desenvolupament, la distribució o la diversitat d'esta vegetació vénen determinats pel règim hidrològic del mateix. De fet, en entorns semiárids, no sols la freqüència i intensitat de les avingudes, sinó també la quantitat d'aigua capil·lar disponible en la zona superficial del sòl, així com l'accessibilitat al nivell freàtic, condicionen tant la presència com el benestar de la vegetació. L'objectiu fonamental d'esta tesi doctoral és el desenvolupament i implementació d'un model ecohidrológic dinàmic, de distribució espai-temporal de la vegetació de ribera a escala de tram que, incloent nous processos o replantejant la definició dels ja inclosos en els models de referència, millore els resultats que poden obtindre's amb els models actualment disponibles. Així mateix, es pretén demostrar la utilitat del nou model per mitjà de l'anàlisi de la resposta dinàmica de la vegetació de ribera a escala de tram enfront de diferents escenaris de canvi global. A fi d'adquirir l'autonomia i el

Global circulation models forecasts indicate a future temperature and rainfall pattern modification worldwide. Such phenomena will become particularly evident in Europe where climate modifications could be more severe than the average change at the global level. As such, river flow regimes are expected to change, with resultant impacts on aquatic and riparian ecosystems. Riparian woodlands are among the most endangered ecosystems on earth and provide vital services to interconnected ecosystems and human societies. However, they have not been the object of many studies designed to spatially and temporally quantify how these ecosystems will react to climate change-induced flow regimes. Our goal was to assess the effects of climate-changed flow regimes on the existing riparian vegetation of three different European flow regimes. Cases studies were selected in the light of the most common watershed alimentation modes occurring across European regions, with the objective of appraising expected alterations in the riparian elements of fluvial systems due to climate change. Riparian vegetation modeling was performed using the CASiMiR-vegetation model, which bases its computation on the fluvial disturbance of the riparian patch mosaic. Modeling results show that riparian woodlands may undergo not only at least moderate changes for all flow regimes, but also some dramatic adjustments in specific areas of particular vegetation development stages. There are circumstances in which complete annihilation is feasible. Pluvial flow regimes, like the ones in southern European rivers, are those likely to experience more pronounced changes. Furthermore, regardless of the flow regime, younger and more water-dependent individuals are expected to be the most affected by climate change.

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

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.

El modelo RibAV es útil en la determinación de índices de evapotranspiración. Una vez calibrado/validado el modelo, es posible zonificar diferentes tipos funcionales de vegetación presentes en las riberas. Bajo diferentes hipótesis de escenarios hidrológicos y climáticos se ha analizado la zonación en varios tramos de ríos de la CHJ.