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The influence of the sea and topography are vital factors in the atmospheric processes affecting any island, as they introduce peculiarities in the hydrosedimentary response of fluvial systems. In view of that, the relationship between the surface atmospheric conditions (weather types, WTs), rainfall, runoff and erosion dynamics in three small catchments located in Mallorca were analysed. The catchments are representative in terms of geomorphology and land use but also due to their location within the major rainfall areas previously identified in the island by (Sumner et al., 1993). Data of rainfall, runoff and sediment variables, coupled with calculated WTs were used for the 2013–2017 period. WTs frequency and distribution during this period were compared to the last climatic period reference (1981–2010) to test the climate validity of the study period. The results illustrated how hydrosedimentary response was mostly caused by eco-geographical patterns but also by differences in the response of each catchment to WTs, related to the intrinsic geographical position in the island and different exposures to humid winds. Anticyclonic WT was the most frequent, despite it being only involved in one flood event at the eastern catchment. Conversely, eastern and northeastern WTs generated more than 85% of the total runoff and sediment, representing only 39% of flood events. The understanding of the specific role of WTs on the island's hydrology was improved, considering that freshwater resources are scarce and eco-sociologically crucial.

Soil moisture conditions play a key role in runoff and sediment load dynamics in river catchments of contrasting ecosystems. However, the highly marked seasonality of Mediterranean climate affects hydrological processes and sediment transport strongly, as evapotranspiration determines a succession of wet, transition and dry periods throughout a hydrological year. This study examines results of soil moisture, water and sediment fluxes during five hydrological years in a representative small mid-mountain Mediterranean catchment. It aims to assess the sediment load contribution and its variability at different temporal scales. Precipitation, runoff and suspended sediment load were calculated at annual, seasonal and event scales to assess inter- and intra-annual variability. A database with 45 events was used to identify the main controlling factors over sediment load thought bivariate relationships and an analysis of soil moisture-discharge and discharge-suspended sediment concentration hysteresis. At the annual scale, lithology, land use and soil conservation structures characteristic of the catchment caused low values of sediment yield, although inter-annual rates varied by up to three orders of magnitude (0.08 to 11.86 t km−2 y−1). Seasonal analysis of accumulated sediment load showed that 80% was generated during the autumn and winter seasons. At the event scale, streamflow and soil moisture were the controlling factors for the largest sediment load contributions. The highest frequency of clockwise discharge-suspended sediment concentration hysteresis revealed that most of the sediment was generated from nearby sources, although the largest sediment loads were contributed under wet antecedent conditions, as depicted by the soil moisture-discharge hysteresis assessment.

Mediterranean-climate catchments are characterized by significant spatial and temporal hydrological variability caused by the interaction of natural as well human-induced abiotic and biotic factors. This study investigates the non-linearity of rainfall-runoff relationship at multiple temporal scales in representative small Mediterranean-climate catchments (i.e., <10 km2) to achieve a better understanding of their hydrological response. The rainfall-runoff relationship was evaluated in 43 catchments at annual and event—203 events in 12 of these 43 catchments—scales. A linear rainfall-runoff relationship was observed at an annual scale, with a higher scatter in pervious (R2: 0.47) than impervious catchments (R2: 0.82). Larger scattering was observed at the event scale, although pervious lithology and agricultural land use promoted significant rainfall-runoff linear relations in winter and spring. These relationships were particularly analysed during five hydrological years in the Es Fangar catchment (3.35 km2; Mallorca, Spain) as a temporal downscaling to assess the intra-annual variability, elucidating whether antecedent wetness conditions played a significant role in runoff generation. The assessment of rainfall-runoff relationships under contrasted lithology, land use and seasonality is a useful approach to improve the hydrological modelling of global change scenarios in small catchments where the linearity and non-linearity of the hydrological response—at multiple temporal scales—can inherently co-exist in Mediterranean-climate catchments.

[ES] Los instrumentos musicales de viento metal que se emplean en la actualidad son fruto de diseños artesanales realizados hace aproximadamente un siglo. En este TFG se introduce el estudio de los parámetros de calidad que permitan validar un correcto diseño de una boquilla de trompa aplicando una metodología novedosa. Este nuevo concepto ha permitido el estudio de la calidad de una boquilla sin necesidad de fabricar ningún prototipo. Este proyecto pretende convertirse en el inicio de una nueva línea de aplicación que permita rediseñar los instrumentos musicales de viento metal con el fin de solucionar los problemas que escapan a las limitaciones del diseño artesanal., [CA] Els instruments musicals de vent metall que s'empren en l'actualitat són fruit de dissenys artesanals realitzats fa aproximadament un segle. En aquest TFG s'introdueix l'estudi dels paràmetres de qualitat que permeten validar un correcte disseny d'una boquilla de trompa aplicant una metodologia nova. Aquest nou concepte ha permès l'estudi de la qualitat d'una boquilla sense necessitat de fabricar cap prototip. Aquest projecte pretén convertir-se en el inici d'una nova línia d'investigació que permeti re-dissenyar els instruments musicals de vent metall per tal de solucionar els problemes que escapen a les limitacions del disseny artesanal., [EN] Musical brass instruments that are played nowadays are the result of handmade designs created over a century ago. In this project the study of quality parameters to validate proper design of a mouthpiece using a new methodology is introduced. This new concept has allowed the study of the quality of a mouthpiece without making any prototype. This project aims to become the beginning of a new line of research to redesign the musical brass instruments in order to solve problems that are beyond the limitations of the handmade design.