Search results for " basin"

Ecohydrological modelling of flow duration curve in Mediterranean river basins

2013

Abstract Flow duration curve provides an important synthesis of the relevant hydrological processes occurring at the basin scale, and, although it is typically obtained from field observations, different theoretical approaches finalized to its indirect reconstruction have been developed in recent years. In this study a recent ecohydrological model for the probabilistic characterization of base flows is tested through its application to a study catchment located in southern Italy, where long historical series of daily streamflow are available. The model, coupling soil moisture balance with a simplified scheme of the hydrological response of the basin, provides the daily flow duration curve. …

Long-Term Hydrological Regime Monitoring of a Mediterranean Agro-Ecological Wetland Using Landsat Imagery: Correlation with the Water Renewal Rate of…

2021

The Natural Park of Albufera (Valencia, Spain) is one of the Spanish Mediterranean wetlands where rice is cultivated intensively. The hydrology of the Albufera Lake, located in the center, combines natural contributions with complex human management. The aim of our study was to develop a new methodology to accurately detect the volume of flood water in complex natural environments which experience significant seasonal changes due to climate and agriculture. The study included 132 Landsat images, covering a 15-year period. The algorithm was adjusted using the NDWI index and simultaneous measurements of water levels in the rice fields. The NDVI index was applied to monitor the cultivated area…

Drought Management Decision Support System by Means of Risk Analysis Models

2007

Droughts in arid and semiarid Mediterranean river basins have an increasing socioeconomic and environmental impact. The problem is especially complex in basins where droughts are very frequent and intense and where water resources are under a massive use. For that reason in the Mediterranean basins it is necessary to manage the water resources in constant alert in order to relieve the consequences of a drought. In this chapter a complete methodology for the mitigation of the droughts is defined. The methodology includes different tools: from the definition of an alert system for the different types of drought up to the simulation and optimization software for water system management. This m…

Las crecidas en ramblas valencianas mediterráneas

2001

This paper takes into account the characterisation of ephemeral stream hydrology from Mediterranean environments. The heavy floods that these countries suffer are due to firstly, the physical watershed features (steep slopes, scarced vegetation cover and thin soils) and, secondly, to the intense and variable rainfall. Large quantities of precipitation fall in a matter of hours, or even minutes, over very steep catchments, causing catastrophic flash-floods, with very pointed hydrographs and short time lags. Using hydrological daily data from the Rambla de la Viuda basin and five-minute data from both Barranc de Carraixet and Rambla de Poyo basins, we have analysed the rainfall- runoff proces…

Sea surface temperature and torrential rains in the Valencia region: modelling the role of recharge areas

2015

Abstract. Heavy rain events are frequently recorded in the Western Mediterranean causing economic losses and even human casualties. The Western Mediterranean is a deep and almost closed sea surrounded by high mountain ranges and with little exchange of water with the Atlantic ocean. A main factor in the development of torrential rains is ocean-atmosphere exchanges of heat and moisture that can potentially destabilize air masses travelling over the sea. The study of air mass trajectories previous to the rain event permits the identification of sea areas that could probably contribute to the development or intensification of rainfall. From a previous Mediterranean sea surface temperature clim…

Dietary fiber intake and the Mediterranean population

2020

Abstract Dietary fiber encompasses carbohydrates not digested or absorbed in the small intestine, arriving intact to the colon. Its role in human health has been mentioned since the times of Hippocrates but only in the 1970s of the 20th century, and subsequently a myriad of epidemiological and clinical studies has shown that a diet with low content of dietary fiber is associated with several chronic diseases such as diabetes, cardiovascular diseases, certain neoplastic diseases, specially colon cancer, and also obesity. The Western dietary pattern, which is spreading in our current globalized world and in which many components are ultraprocessed, has very low fiber content. Conversely the M…

Long-term impact of rainfed agricultural land abandonment on soil erosion in the Western Mediterranean basin

2018

[EN] Land abandonment is widespread in the Mediterranean mountains. The impact of agricultural abandonment results in a shift in ecosystem evolution due to changes in soil erosion, but little is known about long-term soil and water losses. This paper uses 11 years of measurements in two paired plots (abandoned vs control) with four subplots to determine how soil and water losses evolved after abandonment within an agricultural parcel. For two years (2004¿2005) both plots were under tillage, and after 2006 one plot was abandoned. The monitored plots measured runoff and sediment concentration after each rainfall event.

An anomalous case in the evolution of the Mesozoic sedimentary basins between Alpine and Ionian Tethys: the Panormide Carbonate Platform (Sicily).

2007

Transtensional/extensional fault activity from the Mesozoic rifting to Tertiary chain building in Northern Sicily (Central Mediterranean)

2005

Extensional structures of different ages characterize the Sicilian fold-and-thrust belt. Normal faults ranging in geometry from stepped to listric and formed in different geodynamic settings significantly controlled the pattern of syn-tectonic deposits. Since Mesozoic times Sicily has experienced deformation related to the opening of the Tethys Ocean. Between the Upper Triassic and the Cretaceous normal, strike- and oblique-slip faults, developed in northern Sicily, in the framework of a transtensional deformation regime induced by the oblique rifting of the African and European continental passive margins. Since Tertiary times a reversal in the general relative plate motion induced converg…

Noble gas and CO2 isotopic signatures of the lithospheric mantle underneath Mexico and the Canary Islands: clues from mantle xenoliths and arc lavas

2022

Studying the isotopic composition of fluids trapped in mantle xenoliths opens avenues to understand the origin and cycling of volatiles in the Earth’s upper mantle. In this PhD dissertation, new and in most cases the very first data regarding the isotopic (noble gases and CO2) characterization of the lithospheric mantle portions of three different geodynamic environments are presented: (i) Central and NW Mexico, a continental setting dominated by extension; (ii) the Transmexican Volcanic Belt (TMVB) a subduction setting, and (iii) the Canary Islands, particularly El Hierro and Lanzarote, two oceanic islands formed by mantle plume-derived intraplate volcanism. In total 32 peridotites (includ…