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Floods are a consequence of extreme rainfall events. Although surface runoff generation is the origin of discharge, flood research usually focuses on lowlands where the impact is higher. Runoff and sediment delivery at slope and pedon scale receiving much less attention in the effort to understand flood behaviour in time and space. This is especially relevant in areas where, due to climatic and hydrogeological conditions, streams are ephemeral, so-called dry rivers (“wadis”, "ramblas" or “barrancos”) that are widespread throughout the Mediterranean. This paper researches the relationship between water delivery at pedon and slope scale with dry river floods in Macizo del Caroig, Eastern Iberian Peninsula. Plots of 1x1, 1x2, 1x4, and 2x8 m located in the “El Teularet” Soil Erosion and Degradation Research Station were monitored from 2004 to 2014 to measure soil and water delivery. Rainfall and flow at the dry river Barranco de Benacancil were also monitored. Results show that runoff and sediment discharge were concentrated in few events during the 11 years of research. A single flood event was registered in the channel on September 28, 2009, however, the runoff was registered 160 times at the plots. Runoff discharge was dependent on the size of the plots, with larger plots yielding lower runoff discharge per unit area, suggesting short runoff-travel distance and duration. Three rainfall events contributed with 26% of the whole runoff discharge, and five achieved 56% of the runoff. We conclude that the runoff generated at the plot scale is disconnected from the main channel. From a spatial point of view, there is a decrease in runoff coefficient along the slope. From a temporal point of view, the runoff is concentrated in a few rainfall events. These results show that the runoff generated at plot and slope scale does not contribute to the floods except for rainfall events with more than 100 mm day-1. The disconnection of the runoff and sediment delivery is confirmed by the reduction in the runoff delivery at plot scale due to the control of the length of the plot (slope) on the runoff and sediment delivery.

El temporal Glòria va suposar per a molts rius a Catalunya una reestructuració completa de la seva morfologia fluvial. Els cabals van assolir magnituds molt importants, que van provocar canvis profunds en la forma de la llera, van produir incisió i eixamplament generalitzades, van inundar planes d’inundació, i van reconnectar braços abandonats. L’episodi va contribuir a reactivar profundament els sistemes fluvials, i els rius van experimentar un grau de metamorfisme com feia dècades que no es veia. L’estudi mostra també el paper de les grans preses en la modificació dels hidrogrames de crescuda. El Glòria va trobar uns rius confinats per l’activitat antròpica, amb els balanços de sediments en desequilibri i en clara desconnexió hídrica i sedimentària amb la conca. Unes hores de pluja intensa i la subseqüent resposta hidrològica de les conques van aportar l’energia suficient per superar molts dels llindars físics als que estaven sotmesos, i canviar per molt de temps la morfologia de les lleres i valls afectades. El temporal Gloria supuso para muchos ríos en Catalunya una reestructuración completa de su morfología fluvial. Los caudales alcanzaron magnitudes muy importantes, provocando cambios profundos en la forma de los cauces, produciendo incisión y ensanchamiento generalizados, inundando las llanuras aluviales, y reconectando brazos abandonados. El episodio contribuyó a reactivar profundamente los sistemas fluviales, y los ríos experimentaron un grado de metamorfismo como no se había visto en décadas. El estudio muestra también el papel de las grandes presas en la modificación de los hidrogramas de crecida. El Gloria encontró ríos constreñidos por la actividad antrópica, con los balances de sedimento en desequilibrio y en clara desconexión hídrica y sedimentaria con la cuenca. Unas horas de lluvia intensa y la subsiguiente respuesta hidrológica de las cuencas aportaron la energía suficiente para superar muchos de los límites físicos alos que estaban sometidos, y cambiar por mucho tiempo la morfología de los cauces y valles afectados. Many rivers in Catalonia undertook a complete restructuring of its fluvial morphology under the effects of the storm Gloria. High magnitude flows caused profound changes in channel morphology, producing widespread incision and widening, flooding floodplains, and reconnecting abandoned channels. The episode contributed to a profound reactivation of river systems, and channels experienced a degree of metamorphism that had not been seen for decades. The study also shows the role of large dams in modifying flood hydrographs. The Gloria found rivers constrained by long-lasting human activity, with sediment balances in complete disequilibrium, and in clear water and sedimentary disconnection with the upstream river basin. Few hours of heavy rain and the subsequent hydrological response of the basins provided enough energy to exceed many of the physical thresholds to which they were subjected, and change the morphology of the affected river channels and valleys for a long time. Aquest treball s’ha realitzat gràcies al suport de la Generalitat de Catalunya a través dels Grups de Recerca Consolidats RIUS SGR2017-0459 i GRAM SGR2017-1344, i del Programa CERCA. Damià Vericat gaudeix d’un contracte de Professor Agregat Serra Húnter de la Generalitat de Catalunya. Els resultats obtinguts en diversos projectes de recerca (e.g. Consolider Ingenio 2010 CSD2009-00065, CGL2012-36394, CGL2016-78874) finançats pel Ministerio de Ciencia e Innovación i Fons FEDER, han contribuït a la formulació d’algunes de les idees que s’exposen en aquets treball.

Los incendios pueden tener lugar en cualquier lugar del planeta. Incendios siempre ha habido y siempre habrá. Cada ecosistema responderá de manera diferente, ya que, de hecho, muchos paisajes han sido modelados por el fuego. Se describen algunos aspectos importantes, como el régimen de incendios, o la paradoja de los incendios. Se analizan las causas, sus efectos y se concluye que solo con un buen conocimiento del problema se pueden encontrar soluciones., Fires can take place anywhere on the planet. It is a phenomenon that has exists and always will be present. Each ecosystem will respond differently to a fire, in fact, many landscapes have been modeled by fire. Some important aspects are described, such as the fire regime, or the paradox of fires. The causes and the effects of fires are analyzed and it is concluded that only with a good knowledge of the problem we can find solutions.

Trabajo presentado en TERRAenVISION Environmental Issues Today: Scientific Solutions for Societal Issues, celebrado en Barcelona (España) del 27 de enero al 2 de febrero de 2018, This contribution results from international collaborative efforts of different research groups around the Mediterranean basin focusing on soil conservation and water management. We will present the most complete database of runoff and soil erosion information and analyze the records from 68 locations, including more than 22458 detail events between 1985-2015. Soil conservation and water planning are two of the most challenging problems around the Mediterranean basin due to climate conditions and human activity. We believe that future advances on understanding soil degradation by water should be developed under global approaches. In this contribution, we will present an analysis of atmospheric conditions, expressed by weather types and the resulted rainfall, runoff, and erosion and sediment yield around the Mediterranean basin. The weather types compile daily information about the different air masses responsible for rainfall, runoff and eventually erosion and sediment yield, and their analyses let us know the synchrony of the response at different sites around the Mediterranean basin. The analyses of the global dataset display different spatial patterns for rainfall, runoff, and sediment yield, related to different atmospheric patterns. This research will be a valuable tool for understanding the evolution of these environmental variables, and therefore it will allow future planning to design regional water management and soil conservation measures

Fires can take place anywhere on the planet. It is a phenomenon that has exists and always will be present. Each ecosystem will respond differently to a fire, in fact, many landscapes have been modeled by fire. Some important aspects are described, such as the fire regime, or the paradox of fires. The causes and the effects of fires are analyzed and it is concluded that only with a good knowledge of the problem we can find solutions. Los incendios pueden tener lugar en cualquier lugar del planeta. Incendios siempre ha habido y siempre habrá. Cada ecosistema responderá de manera diferente, ya que, de hecho, muchos paisajes han sido modelados por el fuego. Se describen algunos aspectos importantes, como el régimen de incendios, o la paradoja de los incendios. Se analizan las causas, sus efectos y se concluye que solo con un buen conocimiento del problema se pueden encontrar soluciones.