ABSTRACT:In southern Spain a longitudinal pluviometric gradient occurs under Mediterranean climatic conditions in an area that has at least two months of drought each year and very irregular rainfall. From the Strait of Gibraltar to the Cabo de Gata in Almería there is a reduction of more than 1,000 mm year −1 in the mean annual rainfall. Analysis of the frequency and intensity of drought periods is necessary in regions where water resources are scarce and the ecosystem is highly dependent on water availability. Drought periods in the region described above were analysed using the DDSLR (Dry Days Since Last Rain) index to i) characterize trends in number of dry days and the amount of rainfall along the pluviometric gradient, ii) assess how the DDSLR index changes along the gradient from semiarid to humid Mediterranean regions, and iii) contribute to studies addressing the importance of climatic gradients in relation to the dynamics of various ecosystems. The DDSLR method enables calculation of the probability of the occurrence of dry days (days without rain) at any time of the year, assessment of the risk of water deficits for vegetation during plant growth periods, and evaluation of the temporal variability of hydrological/geomorphological processes that depend on soil moisture throughout the year. The results showed that there is a critical period of rainfall scarcity during September and October, which has implications for the availability of soil water resources for vegetation.In short-term, the major problems are predicted for the Spanish Southern Mediterranean due to the increasing irregularity in precipitations: the number of days with no rains and drought periods are increased, but also a significant increment in the probabilities of extreme rainfalls exceeding 30 mm day −1 .

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Rangelands are a major component of the Mediterranean landscape. These environments are commonly affected by grazing, which reduces vegetation cover. Consequently, patchy vegetation patterns occur on Mediterranean hillslopes, where the bare soil is characterized by a number of surface components that are controlled by climatic conditions and exposure. The aim of this study was to assess at a fine scale the effects of exposure, scrub, and soil surface components on the hydrological response under various Mediterranean climatic conditions. A set of closed plots (each of area 1Ð3 m 2 ) were established in each of three Mediterranean rangeland environments that differ in climatic conditions (humid, dry, and semiarid), but were not affected by intensive grazing. Rainfall was recorded at a meteorological station installed at each field site, and topsoil moisture was measured after every rainfall event, when run-off was collected. The results showed that (i) run-off was generated when topsoil moisture was close to saturation in the case of humid sites, and close to the wilting point at dry and semi-arid sites; (ii) run-off did not follow the same trends as rainfall and topsoil moisture along the climatic gradient because of the effects of soil surface components; (iii) the hydrological response in the plots was not clearly controlled by exposure and the location of scrub, especially at the semi-arid site; and (iv) the differences between field sites were small because of the influence of grazing on vegetation cover and the effects of soil water repellency, both of which require further investigation.

resumen | En las últimas décadas se ha implementado en el litoral mediterráneo español un modelo turístico basado en la construcción de complejos residenciales próximos a la costa, la mayoría de ellos asociados a un campo de golf, con viviendas adquiridas en general por ciudadanos de otros países europeos. Este proceso (1995-2007) ha generado un vigoroso mercado inmobiliario y diversos fenómenos socioespaciales, como gentrificación, segregación, homogeneización o fragmentación del espacio urbanizado, en un modelo que ha sido exportado a diversos lugares, como el continente americano. El objetivo de la presente investigación es analizar la difusión del modelo turístico español hacia Brasil, concretamente su presencia en Polo Costa das Dunas, en el Estado de Rio Grande do Norte. Esta transmisión se debe principalmente a las empresas constructoras de capital europeo que invierten en el citado territorio. La conclusión más relevante es la difusión y traslado, a otras realidades, de los procesos socioespaciales urbanos que caracterizan el modelo turístico residencial español. palabras clave | mercado inmobiliario, transformaciones socioterritoriales, geografía urbana. abstract | In recent decades, a tourist model based on the construction of residential complexes close to the coast has been implemented on the Spanish Mediterranean coast, with homes generally acquired by citizens of other European countries. This process has generated a vigorous real estate market (1995-2007) and various socio-spatial phenomena, such as gentrification, segregation, homogenization or fragmentation of the urbanized space, in a model that has been exported to various places, such as the American continent. The objective of the present investigation is to analyze the diffusion of the Spanish tourist model towards Brazil, specifically its presence in Polo Costa das Dunas, in the State of Rio Grande do Norte. This transmission is mainly due to the European capital construction companies that invest in the aforementioned territory. The most relevant conclusion is the dissemination and transfer of the urban socio-spatial processes that characterize the Spanish residential tourism model. keywords | real-estate market, socio-territorial transformations, urban geography.

The scarcity of water in the Campo de Cartagena has limited its exploitation, which is why, historically, runoff water has been used through sustainable traditional practices which have been dismissed by technological advances. In order to demonstrate the potential of this resource at present, an analysis by interpolation of rainfall distribution in the sub-basin of the Rambla de Fuente Álamo-Albujón was carried out (for the intense rainfall episodes of 2012 and 2016) as well as hydraulic modelling of the estimation of surface runoff. In addition, taking into account the future climate scenarios, a projection of the total runoff in the study area was made up to the year 2100. The bibliographic review and the press analysis showed that the traditional use of runoff water has remained in disuse, although there are infrastructures to collect water from floods but with an eminently sanitary purpose. The current model of agricultural and touristic exploitation is giving rise to serious socio-environmental conflicts which manifest in obsolescence. Therefore, the increase in the availability of water with the use of a specific endogenous resource may lead to a decrease in the pressures exerted on the study area.