Search results for "feature"
showing 10 items of 4091 documents
Assessment of channel changes in a Mediterranean ephemeral stream since the early twentieth century. The Rambla de Cervera, eastern Spain
2013
An analysis of morphological changes during the last six decades is presented for a 16.5-km reach of the Rambla de Cervera, a Mediterranean ephemeral stream located in eastern Spain. Channel changes were analysed through a range of techniques, specifically the analysis of aerial photographs with geographical information systems (GIS) and comparison of topographic surveys. The gravel channel underwent a general decline over the study period, losing width (68.5%) and surface area (45.7%). Incision ocurred along the entire study reach at an average depth of 3.5 m. Natural and human-induced factors producing contradictory effects are considered responsible for changes in the Rambla de Cervera
Sensitivity of precipitation forecasts to convective parameterization in the October 2007 Flash Flood in the Valencia Region (Eastern Spain)
2018
Abstract. The Valencia region, on the Mediterranean coast of the Iberian Peninsula, is an area prone to torrential rains, especially the north of Alicante province and the south of Valencia province. In October 2007, a torrential rain event with accumulated rainfall values exceeding 400 mm in less than 24 h affected the aforementioned areas, producing flash floods that caused extensive economic losses and human casualties. Several simulations of this rain event have been performed with the Regional Atmospheric Modeling System (RAMS) to test the influence of the different convective parameterization scheme implemented in the model on the precipitation forecast.
Plot-scale measurement of soil erosion at the experimental area of Sparacia (southern Italy)
2004
Obtaining good quality soil loss data from plots requires knowledge of the factors that affect natural and measurement data variability and of the erosion processes that occur on plots of different sizes. Data variability was investigated in southern Italy by collecting runoff and soil loss from four universal soil-loss equation (USLE) plots of 176 m2, 20 ‘large’ microplots (0·16 m2) and 40 ‘small’ microplots (0·04 m2). For the four most erosive events (event erosivity index, Re ≥ 139 MJ mm ha−1 h−1), mean soil loss from the USLE plots was significantly correlated with Re. Variability of soil loss measurements from microplots was five to ten times greater than that of runoff measurements. D…
Pharmaceuticals and personal care products in a Mediterranean coastal wetland: Impact of anthropogenic and spatial factors and environmental risk ass…
2021
The present study focused on the occurrence, distribution and risk assessment of 32 pharmaceuticals and personal care products (PPCPs) in water and sediment, as well as the surrounding soil of the irrigation channels and lake of a Mediterranean coastal wetland, the Albufera Natural Park (Valencia, Spain). Moreover, the influent and effluent of ten wastewater treatment plants (WWTPs) that treat wastewater from Valencia and the surrounding areas were also studied. BPA, caffeine, diclofenac, ethyl paraben, methyl paraben, metformin, tramadol and salicylic acid were the predominant PPCPs detected in the channels and the lake, and are in good agreement with those detected in the effluent. Furthe…
Post-fire soil functionality and microbial community structure in a Mediterranean shrubland subjected to experimental drought.
2016
Fire may cause significant alterations in soil properties. Post-fire soil dynamics can vary depending, among other factors, on rainfall patterns. However, little is known regarding variations in response to post-fire drought. This is relevant in arid and semiarid areas with poor soils, like much of the western Mediterranean. Furthermore, climate change projections in such areas anticipate reduced precipitation and longer annual drought periods, together with an increase in fire severity and frequency. This research evaluates the effects of experimental drought after fire on soil dynamics of a Cistus-Erica shrubland (Central Spain). A replicated (n = 4) field experiment was conducted in whic…
A test on Ellenberg indicator values in the Mediterranean evergreen woods (Quercetea ilicis)
2015
The consistency and reliability of Ellenberg’s indicator values (Eiv) as ecological descriptors of the Mediterranean evergreen vegetation ascribed to the phytosociological class Quercetea ilicis have been checked on a set of 859 phytosociological releves × 699 species. Diagnostic species were identified through a Twinspan analysis and their Eiv analyzed and related to the following independent variables: (1) annual mean temperatures, (2) annual rainfall. The results provided interesting insights to disentangle the current syntaxonomical framework at the alliance level demonstrating the usefulness of ecological indicator values to test the efficiency and predictivity of the phytosociological…
Isotope evidence for the use of marine resources in the Eastern Iberian Mesolithic
2014
There are relatively few coastal Mesolithic sites in the Iberian Mediterranean region, probably due to a number of factors including sea level changes and the disappearance of sites due to agriculture and urbanisation. However, recent excavations have uncovered inland sites that have marine faunal remains (i.e. molluscs and fish) and lithics from the coastal area, which both indicate interactions between the coast and the upland valleys. These inland sites are located at a distance of 30-50km from today's coastline and are at altitudes higher than 1000m. We report on additional information on the links between the coast and these inland sites through the use of dietary isotope analysis (car…
Late Mesolithic burials at Casa Corona (Villena, Spain): direct radiocarbon and palaeodietary evidence of the last forager populations in Eastern Ibe…
2013
Abstract Current knowledge about the Mesolithic–Neolithic transition in the Central and Western Mediterranean European regions is deeply limited by the paucity of Late Mesolithic human osteological data and the presence of chronological gaps covering several centuries between the last foragers and the first archaeological evidence of farming peoples. In this work, we present new data to fill these gaps. We provide direct AMS radiocarbon dating and carbon (δ13C) and nitrogen (δ15N) stable isotope analysis were carried out on bone collagen samples of two single burials from the recently discovered open-air Late Mesolithic site of Casa Corona (Villena, Spain). The results shed new light on the…
Economic transitions in finis terra
2009
A gradualist approach has been taken in describing the evolution of the last foragers in the Iberian Mediterranean Region (IMR) up to their rapid collapse, brought about by the appearance of the first prehistoric farmers. This point of view assumes that the post-Last Glaical Maximum (LGM) climatic change brought about a certain restructuring of the mammal fauna and exerted a direct influence by flooding the changing coastal plain and submerging coastal sites related to marine resource use. This paper proposes that small prey was a constant and structural resource in the IMR that did not signal intensification, since human consumption of rabbits goes back to the Middle Palaeolithic. At the s…
Ferula sommieriana (Apiaceae), a new species from Pelagie Islands (Sicily)
2021
Ferula sommieriana, a new species occurring in Lampedusa and Linosa, islands of Pelagie Archipelago in the Sicilian Channel, is described and illustrated. Previously it was attributed to F. communis, from which it differs in several features regarding mainly the morphology and anatomy of terminal leaf lobes and mericarps, as well as the shape and size of reproductive structures. Its ecology, conservation status and relationships with other allied Mediterranean species of the sect. Ferula are provided, as well as the analytical keys of the species belonging to the aforesaid section.