Ebro River

Figure 13.15 Chromatograms obtained by on-line ti ace enrichment of 50 ml of Ebro river water with and without the addition of different volumes of 10% Na2S03 solution for every 100 ml of sample (a) blank with the addition of 1000 p.1 of sulfite (b) spiked with 4 p.g 1 of the analytes and 1000 p.1 of sulfite (c) spiked with 4 p.g 1 of the analytes and 500 p.1 of sulfite (d) spiked with 4 p.g 1 of the analytes without sulfite. Peak identification is as follows 1, oxamyl 2, methomyl 3, phenol 4, 4-niti ophenol 5, 2,4-dinitrophenol 6, 2-chlorophenol 7, bentazone 8, simazine 9, MCPA 10, atrazine. Reprinted from Journal of Chromatography, A 803, N. Masque et ai, New chemically modified polymeric resin for solid-phase extraction of pesticides and phenolic compounds from water , pp. 147-155, copyright 1998, with permission from Elsevier Science.

Case Study Occurrence of Pharmaceuticals and Illicit Drugs in the Ebro River Basin... 

Wastewater from seven WWTPs, located in the main cities in the Ebro river basin (Pamplona, Logrono, Miranda de Ebro, Zaragoza, Tudela, Lleida, Tortosa), as well as the receiving river waters downstream the plants were monitored for the presence... 

Fig. 4 Concentrations (ng L ) of the most ubiquitous analgesics and anti-inflammatories, lipid regulators, psychiatric drugs and [I-blockers detected in (a) wastewater effluents and (b) river water downstream of the three WWTP in the Ebro river basin in relationship to the dilution factor...

Gros M, Petrovic M, Barcelo D (2007) Wastewater treatment plants as a pathway for aquatic contamination by pharmaceuticals in the ebro river basin (northeast Spain). Environ Toxicol Chem 26(8) 1553-1562... 

Navarro-Ortega A, Tauler R, Lacortc S, Barcelo D (2010) Occurrence and transport of PAHs, pesticides and alkylphenols in sediment samples along the Ebro River Basin. J Hydrol 383... 

Postigo C, Lopez de Alda MJ, Barcelo D (2010) Drugs of abuse and their metabolites in the Ebro river basin occurrence in sewage and surface water, sewage treatment plants removal efficiency, and collective drug usage estimation. Environ Int 36(l) 75-84... 

The Physical Framework and Historic Human Influences in the Ebro River... 

Keywords Biogeochemistry, Ebro River watershed, Human settlements, Land use, Nutrient content, Physiography... 

The Ebro River basin is located in the NE of the Iberian Peninsula, occupying a total surface of 85,362 Km2. Most of the watershed surface area is in Spanish territory, but small parts drain in Andorra and in France (445 km2 and 502 km2, respectively). The Ebro River is the largest hydrographic basin in Spain, accounting for 17.3% of its total surface area. 

The Cantabrian Mountains and the Pyrenees in the North, the Iberian System in the South-East, and the Coastal Catalan mountains in the East are the natural limits of the Ebro River basin. Traditionally, the river source was supposed to be at Fontibre (name derived from Forties Iberis in latin, Springs of Iberia ) at 880 m.a.s.l., near Reinosa in Cantabria. Nowadays, the river source is placed at 1,980 m.a.s.l., the water coming from a source in Penalara (27 km upstream from Reinosa). The main river channel is 910 km in length, flows NW-SE, from the Cantabrian Mountains to the Mediterranean Sea, where it forms a delta. 

This chapter describes the main physical characteristics of the Ebro River, including the watershed orography, the biogeography and vegetation, the climatic and hydrological characteristics, and the soil type and biogeochemistry of river Ebro waters. The Ebro watershed has historically served as nucleus and connection for humans human settlements are known since pre-historic years and nowadays the river water chemistry cannot be understood without the anthropogenic effects. Therefore, the potential effects of human activities at the Ebro watershed are analyzed. 

Fig. 1 Map of the Ebro River watershed showing the main cities and tributaries. The position of the Ebro with respect to the Iberian Peninsula is also indicated...

Among the natural areas in the Ebro River basin, a broad spectrum of landscapes is scattered, ranging from boreal-alpine coniferous forests, mixed deciduous forests, Mediterranean evergreen and mixed forest and shrubs, and semi-arid treeless formations. 

The topography of the Ebro River basin determines a Mediterranean climate with continental characteristics in most of the river basin as well as a semi-arid climate in the center of the depression. At the western extreme of the basin (Pyrenees and Iberian mountains), there is an oceanic climate. The central part of the basin is isolated from the oceanic influence because of the surrounding mountains. This results in the increase of the continentality of the climate and the drastic decrease of the rainfall. In the central part of the river basin (Zaragoza, Alcaniz, and Lleida urban areas), aridity is the main climatic characteristic. 

The mean annual precipitation in the Ebro River basin is of 622 mm (mean from years 1920-2000), but with a high monthly and annual variability. Long periods of low precipitation are usual in winter and the end of autumn, especially in the plain. Higher rainfall occurs in spring and autumn. The rainfall is also irregularly... 

Table 1 Most significant sub-watersheds of the Ebro River basin. Mean annual discharge considering the river at natural regime avoiding detraction, inputs for translocations, regulation or evaporation in the reservoirs. Data from CHE...

The regulation of the Ebro River in the 1960s completed an irreversible change of the discharge pattern. The dams substantially altered flood timing, particularly of the flood peaks [26, 27]. Batalla et al. [28] analyzed flow records from 22 rivers to determine the effects of reservoirs on flow regime (flood frequency, flow duration of mean daily flows, monthly regime, and annual runoff) before and after dam construction. This research shows that variability of the mean daily flows was... 

During the history of the human settlement in the Ebro basin, the river channel has played an important role as a frontier line but also as a communication line. The Ebro River basin was a crucial scenario for hard and bloody battles, such as the Ebro battle which occurred at the lower part of the Ebro basin During the Spanish Civil War (1936-1939). Hydrology played a military role during this battle, with sudden openings of upstream dams in order to interrupt the crossing of the infantry. 

Land use in the Ebro River basin has been traditionally based on agricultural crops, such as vineyards, orchards, and maize. Up to 783,948 Ha are dedicated to agriculture, and mainly in the mid and lower Ebro sections, are irrigated. Nowadays, industry is a relevant activity at the most important cities (e.g., Zaragoza, Pamplona). Hydroelectric energy production uses about 8,297 m3/s in 340 hydroelectric plants at the Ebro River basin. Water of the Ebro River is also used for cooling nuclear and thermic plants. Urban water demand is 5% of that used for agriculture. 

The main economic use of the Ebro River has been hydropower and irrigation. The Ebro River has 187 reservoirs impounding 57% of the mean annual runoff. Such a large number of reservoirs deeply alter the fluvial regimes. None of the major dams in the basin was built for flood control, but the sheer volume of the impoundments affects the flood magnitude. Diverted water is used mainly for hydropower production and for irrigation. All the dams were constructed during the twentieth century,... 

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