Browsing by Subject "Mediterranean mountain"

Now showing 1 - 4 of 4
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    Ecología del paisaje y sistemas de información geográfica ante el cambio socioambiental en las áreas de montaña mediterránea : una aproximación metodológica al caso de los valles d’Hortmoier y Sant Aniol (Alta Garrotxa. Girona)
    (Murcia : Editora Regional de Murcia, 2006) Varga Linde, Diego; Vila Subirós, Josep; Editora Regional de Murcia
    Este artículo es una aproximación a los métodos utilizados para analizar, cuantificar y valorar los cambios en los usos y cubiertas del suelo en estos dos valles que forman parte del espacio natural protegido de la Alta Garrotxa. La dinámica vivida en este territorio es un claro ejemplo de los procesos acaecidos a lo largo del siglo XX en buena parte de las áreas de montaña mediterránea. Una dinámica caracterizada fundamentalmente por un incremento de la superficie forestal en detrimento del espacio agrario. Así mismo se proponen pautas metodológicas para su adecuada cartografía, así como para determinar las áreas potencialmente recuperables de espacio agrario con el objetivo de mantener la diversidad paisajística, biológica y el patrimonio cultural con la ayuda de los SIG y la Ecología del Paisaje.
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    Morfología Fluvial.-Hidrología de un ambiente Mediterráneo de montaña. Las cuencas de Vallcebre (Pirineo Oriental) I. 20 años de investigaciones hidrológicas
    Latron, J.; Llorens, P.; Soler, M.; Poyatos, R.; Rubio, C.; Muzylo, A.; Martínez-Carreras, N.; Delgado, J.; Regüés, D.; Catari, G.; Nord, G.; Gallart, F.; Universidad de Murcia
    ABSTRACT The Vallcebre research catchments are located in a Mediterranean mountain area (Pyrenean range, NE Spain). These catchments were originally covered by Quercus pubescens Willd. and deforested for agricultural use in the past. Nowadays they are covered by mesophyle grasses with spontaneous afforestation by Pinus sylvestris L. In this context, different investigations studying water fluxes in the soil-vegetation-atmosphere continuum have been performed. The main objective of these studies is the analysis and modelling of the role of vegetation cover on the catchment water balance in a framework of climate and land use changes. The dynamics of rainfall interception and transpiration by Scots pines and pubescens oaks, are investigated in terms of their dependence on meteorological conditions, on soil moisture and water table depth. Furthermore, the role of vegetation on catchment water balance is analysed. The results underline: (i) the importance of rainfall interception losses by both tree species and the high temporal variability of this flux, (ii) the effect of forest covers on soil moisture and (iii) the differences in transpiration between species, showing Scots pines a strong reduction of transpiration during droughts. Modelling results indicate that TOPBAL model (a developed version of TOPMODEL for an improved simulation of the response of catchments with diverse vegetation covers and high climatic seasonality) improved the simulation of the catchment water balance.
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    Morfología Fluvial.-Hidrología de un ambiente Mediterráneo de montaña. Las cuencas de Vallcebre (pirineo oriental) III. Vegetación y flujos de agua
    Llorens, P.; Poyatos, R.; Muzylo, A.; Rubio, C.M.; Latron, J.; Delgado, J.; Gallart, F.; Universidad de Murcia
    ABSTRACT The Vallcebre research catchments are located in a Mediterranean mountain area (Pyrenean range, NE Spain). These catchments were originally covered by Quercus pubescens Willd. and deforested for agricultural use in the past. Nowadays they are covered by mesophyle grasses with spontaneous afforestation by Pinus sylvestris L. In this context, different investigations studying water fluxes in the soil-vegetation-atmosphere continuum have been performed. The main objective of these studies is the analysis and modelling of the role of vegetation cover on the catchment water balance in a framework of climate and land use changes. The dynamics of rainfall interception and transpiration by Scots pines and pubescens oaks, are investigated in terms of their dependence on meteorological conditions, on soil moisture and water table depth. Furthermore, the role of vegetation on catchment water balance is analysed. The results underline: (i) the importance of rainfall interception losses by both tree species and the high temporal variability of this flux, (ii) the effect of forest covers on soil moisture and (iii) the differences in transpiration between species, showing Scots pines a strong reduction of transpiration during droughts. Modelling results indicate that TOPBAL model (a developed version of TOPMODEL for an improved simulation of the response of catchments with diverse vegetation covers and high climatic seasonality) improved the simulation of the catchment water balance.
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    Relaciones agua-suelo-vegetación.-Hidrología de un ambiente Mediterráneo de montaña. Las cuencas de Vallcebre (Pirineo Oriental) II. Relaciones precipitación-escorrentía y procesos hidrológicos
    Latron, J.; Soler, M.; Nord, G.; Llorens, P.; Gallart, F.; Universidad de Murcia
    ABSTRACT Hydrological response and runoff processes have been studied in the Vallcebre research basins (North Eastern Spain) for almost 20 years. Results obtained allowed to build a more complete perceptual model of the hydrological functioning of Mediterranean mountains basins. On a seasonal and monthly scale, there was no simple relationship between rainfall and runoff depths. Monthly rainfall and runoff values revealed the existence of a threshold in the relationship between rainfall and runoff depths. At the event scale, the storm-flow coefficient had a clear seasonal pattern. The effect of the water table position on how rainfall and runoff volumes relate was observed. Examination of soil water potential and water table dynamics during representative floods helped to identify 3 types of characteristic hydrological behaviour during the year. Under dry conditions, runoff was generated essentially as infiltration excess runoff in low permeable areas, whereas saturation excess runoff dominated during wetting-up and wet conditions. During wetting-up transition, saturated areas resulted from the development of scattered perched water tables, whereas in wet conditions they were linked to the rise of the shallow water table.