Search results for "Drainage"
showing 10 items of 381 documents
Perfluoroalkyl substances in the Ebro and Guadalquivir river basins (Spain).
2015
Mediterranean rivers are characteristically irregular with changes in flow and located in high population density areas. This affects the concentration of pollutants in the aquatic environments. In this study, the occurrence and sources of 21 perfluoroalkyl substances (PFASs) were determined in water, sediment and biota of the Ebro and Guadalquivir river basins (Spain). In water samples, of 21 analytes screened, 11 were found in Ebro and 9 in Guadalquivir. In both basins, the most frequents were PFBA, PFPeA and PFOA. Maximum concentration was detected for PFBA, up to 251.3ngL-1 in Ebro and 742.9ngL-1 in Guadalquivir. Regarding the sediments, 8 PFASs were detected in the samples from Ebro an…
Multi-method evaluation of denudation rates in small mediterranean catchments
2015
The paper presents the results of the research tasks of the Quantitative Geomorphology Working Group (of the Italian Association of Physical Geography and Geomorphology) focused on multi-method evaluation of denudation rates in small catchments of Italy. Several study areas are compared with the goal of quantifying the morphodynamic evolution in different response times and with traditional and innovative techniques. The final aims are the direct erosion monitoring, the geomorphic analysis for the comprehension of drainage basin morphodynamics, up to the geomorphological hazard evaluation. The catchments are key Mediterranean areas particularly sensitive to climatic and anthropic modificati…
Causes and underlying processes of measurement variability in field erosion plots in Mediterranean conditions
2007
Published online 25 May 2006
Rainfall-runoff modelling of ephemeral streams in the Valencia region (eastern Spain)
2002
This paper presents preliminary results from the application of a transfer-function rainfall–runoff model to ephemeral streams in Mediterranean Spain. Flow simulations have been conducted for two small catchments (Carraixet and Poyo basins), located in close proximity to one another yet with significantly different geological characteristics. Analysis of flow simulations for a number of high-flow events has revealed the dominant influence of the rainfall on the catchment response, particularly for high-rainfall events. Particular success has been attained modelling the highest magnitude events in both catchments and for all events in the faster responding (Poyo) catchment. In order to inves…
Invertebrate community responses to emerging water pollutants in Iberian river basins
2014
Abstract Chemical pollution is one of the greatest threats to freshwater ecosystems, especially in Mediterranean watersheds, characterized by periodical low flows that may exacerbate chemical exposure. Different groups of emerging pollutants have been detected in these basins during the last decade. This study aims to identify the relationships between the presence and levels of prioritary and emerging pollutants (pesticides, pharmaceutical active compounds—PhACs, Endocrine Disrupting Compounds EDCs and Perfluorinated Compounds—PFCs) and the invertebrate community in four Mediterranean basins: the Ebro, the Llobregat, the Jucar and the Guadalquivir. Structural (species composition and densi…
Spatio-temporal distribution of microplastics in a Mediterranean river catchment: The importance of wastewater as an environmental pathway.
2021
Abstract Microplastics (MPs) are considered to be ubiquitous contaminants in freshwater ecosystems, yet their sources and pathways at the river catchment scale need to be better determined. This study assessed MP (55–5000 µm) pollution in a Mediterranean river catchment (central Spain) and aimed to identify the importance of wastewater as an environmental pathway. We sampled treated and untreated wastewaters, and raw and digested sludge from five WWTPs during two seasons. River water and sediments were sampled at three locations with different anthropogenic influences during three seasons. On average, 93% (47–99%) of MPs were retained by WWTPs. Concentrations in river water and sediment ran…
Relationship of Weather Types on the Seasonal and Spatial Variability of Rainfall, Runoff, and Sediment Yield in the Western Mediterranean Basin
2020
Producción Científica
Assessment of the Pressure Level over Lentic Waterbodies through the Estimation of Land Uses in the Catchment and Hydro-Morphological Alterations: Th…
2021
The features of lentic waterbodies largely depend on the surrounding environment. Mediterranean coastal lagoons have been historically altered, with their catchment being highly modified for agricultural, livestock, or urban uses. Changes in land uses induce pressures that impact the waterbodies and alter their ecological status. The objectives of this paper were: to develop a methodological approach (LUPLES: Land Uses for estimating Pressure Levels to approach the Ecological Status), to quantify the main pressures on the waterbodies and to forecast the possible impacts of these pressures on their ecological status. Corine-Land Cover maps and Geographic Information System technics were used…
Lluvias torrenciales y cambios geomórficos en una pequeña cuenca de montaña : el barranco de la Cuesta de la Vega (Valencia)
2013
In this paper the effects of great magnitude -450 mm.- as well as high continued intensity -> 90 mm. for 3h.- storm-rains have been studied for a small mediterranean drainage basin (Ayora, Valencia). Such rains caused anormal flows -between 11.2 y 38.2 m3/sec/km2- and the reactivation of erosiona! and aggradational processes, especially at flat bottomed valleys with terrace culture, where new channels were formed. Severa! types of deposits and erosiona! phenomena are established; among them valley amplitude, local slopes, culture abandonment (in a positive sense ), and valley floor terracing are pointed out.
The crisis facing Tunisian drainage tunnels: identification, analysis and evaluation of water heritage in the Mediterranean region
2014
In regions with Mediterranean and steppe climates, the presence of surface water is sporadic, and a unique – but fragile and undervalued – element of water capture for irrigation and human supply is the ‘qanats’, ‘foggaras’, ‘mkoulas’ or water tunnels. The central objective of this project has been the full study of Tunisia's drainage tunnels. The inventory, analysis and heritage evaluation of Tunisia's ‘qanats’ have been possible through the application of a particular methodology during four annual sessions of fieldwork and analysis in the geographic information system (GIS) laboratory. The results have been: the creation of a spatial data and cartography infrastructure for the Tunisian ‘…