... contaminated sediments: Situation in Spain -51-The problematic of contaminated sediments: A g... more ... contaminated sediments: Situation in Spain -51-The problematic of contaminated sediments: A general view of the situation in Spain MJ Belzunce, J. Franco, R. Castro, A. Borja ... An intensive study is has been done in six estuaries: Nervión, Barbadún, Lea, Oka, Butrón and Artibai ...
In summer 1998 a well-developed anticyclone was found over Flemish Cap. Intense mesoscale activit... more In summer 1998 a well-developed anticyclone was found over Flemish Cap. Intense mesoscale activity, in form of cyclonic rings surrounding the Bank’s periphery, was observed. This dynamical configuration seems to be relevant on considering the distribution of photic layer fertilization-related parameters.
Localización: Actas de las I Jornadas Internacionales sobre reservas marinas: Murcia 24 al 26 de ... more Localización: Actas de las I Jornadas Internacionales sobre reservas marinas: Murcia 24 al 26 de marzo de 1999/coord. por Jose Luis González Serrano, Silvia Revenga Martínez de Pazos, 2001, ISBN 84-491-0492-0, págs. 359-371
Low-salinity waters, within the upper layers of the water column, have been observed in the ocean... more Low-salinity waters, within the upper layers of the water column, have been observed in the oceanic region of the southeastern limit of the Bay of Biscay (in March, 2007). This contribution assesses the potential role of large surface freshwater discharges from the Adour (France), Nervión, Oria, Deba, Urola, Urumea and Bidasoa (Basque Country) rivers, to explain the presence of these
The variability of polycyclic aromatic hydrocarbons (PAH) measured in the soft tissues of Mediter... more The variability of polycyclic aromatic hydrocarbons (PAH) measured in the soft tissues of Mediterranean mussels (Mytilus galloprovincialis) and Pacific oysters (Crassostrea gigas) are investigated. Samples were collected from estuarine waters within the Basque Country (Bay of Biscay), between 2003 and 2011. PAH bioaccumulation showed some seasonality and significant differences were observed between cold (autumn–winter) and warm (spring–summer) seasons. Sites located within the ports of Bilbao and Pasaia showed the highest PAH concentrations in molluscs, and the highest percentages of samples above the established Environmental Quality Standards and Environmental Assessment Criteria. Probably due to human activities carried out in the area, no clear trends were observed, between 2003 and 2011, for the autumn data. Since the Basque coast is an area with high population density and industrial activity, the congener profiles (which reveal the predominance of tetra-aromatics) and the diagnostic ratios identified urban/industrial combustion processes as the main PAH sources. However, natural and petrogenic sources cannot be disregarded.
To do this, egg abundances and environmental data acquired during the Bay of Biscay DEPM survey s... more To do this, egg abundances and environmental data acquired during the Bay of Biscay DEPM survey series, held in May from 1999 to 2002, have been used. The main spawning grounds for each species were identified and the coincidences and dissimilarities in their spatial distribution were analysed, revealing a spatial segregation of the main spawning grounds and a coexistence in secondary spawning grounds.
According to Water Framework Directive requirements, Member States must identify and analyze effe... more According to Water Framework Directive requirements, Member States must identify and analyze effects derived from human pressures in aquatic systems. As different kind of pressures can impact water bodies at different scales, analyses of spatio-temporal evolution of water bodies becomes essential in order to understand ecosystem responses. In this investigation, an analysis of spatio-temporal evolution of sedimentary metal pollution (Cd, Cr, Cu, Hg, Ni, Pb, Zn) in 12 Basque estuaries (Bay of Biscay) is presented. Data collected in extensive sampling surveys is the basis for the GIS-based statistical approach used. The implementation of pollution abatement measures is reflected in a long-term decontamination process, mostly evident in estuaries with highest historical sediment pollution levels. Spatial evolution is determined by either naturally occurring or human driven processes. Such spatial processes are more obviously being reflected in estuaries with lower historical sediment pollution levels.
Using a long-term (1995-2014) monitoring network, from 51 sampling stations in estuaries and coas... more Using a long-term (1995-2014) monitoring network, from 51 sampling stations in estuaries and coasts of the Basque Country (Bay of Biscay), the objective of this investigation was to assess the responsiveness of 83 variables in water (18), sediments (27), biota (26), phytoplankton (2), macroinvertebrates (5) and fishes (5) to different human pressures and management actions. We used a total of 3247 series of data to analyse trends of improvement and worsening in quality. In a high percentage of the cases, the management actions taken have resulted in positive effects in the environment, as shown by the trend analysis in this investigation. Overall, much more trends of improvement than of worsening have been observed; this is true for almost all the media and biological components studied, with the exception of phytoplankton; and it applies as well to almost all the stations and water bodies, with the exception of those corresponding to areas with water treatment pending of accomplishment. In estuaries with decreasing human pressures during the period, the percentage of series showing quality improvement was higher (approx. 30%) than those showing worsening of quality (12%). Moreover, in those water bodies showing an increase of pressure, variables which can be considered indicators of anthropogenic effects showed negative trends (quality worsening). On the other hand, some of the variables analysed were more affected by natural variability than by changes in pressures. That was the case of silicate, nitrate and suspended solids, which followed trends correlated to salinity, which, in turn, was related to the rainfall regime during the study period.
... contaminated sediments: Situation in Spain -51-The problematic of contaminated sediments: A g... more ... contaminated sediments: Situation in Spain -51-The problematic of contaminated sediments: A general view of the situation in Spain MJ Belzunce, J. Franco, R. Castro, A. Borja ... An intensive study is has been done in six estuaries: Nervión, Barbadún, Lea, Oka, Butrón and Artibai ...
In summer 1998 a well-developed anticyclone was found over Flemish Cap. Intense mesoscale activit... more In summer 1998 a well-developed anticyclone was found over Flemish Cap. Intense mesoscale activity, in form of cyclonic rings surrounding the Bank’s periphery, was observed. This dynamical configuration seems to be relevant on considering the distribution of photic layer fertilization-related parameters.
Localización: Actas de las I Jornadas Internacionales sobre reservas marinas: Murcia 24 al 26 de ... more Localización: Actas de las I Jornadas Internacionales sobre reservas marinas: Murcia 24 al 26 de marzo de 1999/coord. por Jose Luis González Serrano, Silvia Revenga Martínez de Pazos, 2001, ISBN 84-491-0492-0, págs. 359-371
Low-salinity waters, within the upper layers of the water column, have been observed in the ocean... more Low-salinity waters, within the upper layers of the water column, have been observed in the oceanic region of the southeastern limit of the Bay of Biscay (in March, 2007). This contribution assesses the potential role of large surface freshwater discharges from the Adour (France), Nervión, Oria, Deba, Urola, Urumea and Bidasoa (Basque Country) rivers, to explain the presence of these
The variability of polycyclic aromatic hydrocarbons (PAH) measured in the soft tissues of Mediter... more The variability of polycyclic aromatic hydrocarbons (PAH) measured in the soft tissues of Mediterranean mussels (Mytilus galloprovincialis) and Pacific oysters (Crassostrea gigas) are investigated. Samples were collected from estuarine waters within the Basque Country (Bay of Biscay), between 2003 and 2011. PAH bioaccumulation showed some seasonality and significant differences were observed between cold (autumn–winter) and warm (spring–summer) seasons. Sites located within the ports of Bilbao and Pasaia showed the highest PAH concentrations in molluscs, and the highest percentages of samples above the established Environmental Quality Standards and Environmental Assessment Criteria. Probably due to human activities carried out in the area, no clear trends were observed, between 2003 and 2011, for the autumn data. Since the Basque coast is an area with high population density and industrial activity, the congener profiles (which reveal the predominance of tetra-aromatics) and the diagnostic ratios identified urban/industrial combustion processes as the main PAH sources. However, natural and petrogenic sources cannot be disregarded.
To do this, egg abundances and environmental data acquired during the Bay of Biscay DEPM survey s... more To do this, egg abundances and environmental data acquired during the Bay of Biscay DEPM survey series, held in May from 1999 to 2002, have been used. The main spawning grounds for each species were identified and the coincidences and dissimilarities in their spatial distribution were analysed, revealing a spatial segregation of the main spawning grounds and a coexistence in secondary spawning grounds.
According to Water Framework Directive requirements, Member States must identify and analyze effe... more According to Water Framework Directive requirements, Member States must identify and analyze effects derived from human pressures in aquatic systems. As different kind of pressures can impact water bodies at different scales, analyses of spatio-temporal evolution of water bodies becomes essential in order to understand ecosystem responses. In this investigation, an analysis of spatio-temporal evolution of sedimentary metal pollution (Cd, Cr, Cu, Hg, Ni, Pb, Zn) in 12 Basque estuaries (Bay of Biscay) is presented. Data collected in extensive sampling surveys is the basis for the GIS-based statistical approach used. The implementation of pollution abatement measures is reflected in a long-term decontamination process, mostly evident in estuaries with highest historical sediment pollution levels. Spatial evolution is determined by either naturally occurring or human driven processes. Such spatial processes are more obviously being reflected in estuaries with lower historical sediment pollution levels.
Using a long-term (1995-2014) monitoring network, from 51 sampling stations in estuaries and coas... more Using a long-term (1995-2014) monitoring network, from 51 sampling stations in estuaries and coasts of the Basque Country (Bay of Biscay), the objective of this investigation was to assess the responsiveness of 83 variables in water (18), sediments (27), biota (26), phytoplankton (2), macroinvertebrates (5) and fishes (5) to different human pressures and management actions. We used a total of 3247 series of data to analyse trends of improvement and worsening in quality. In a high percentage of the cases, the management actions taken have resulted in positive effects in the environment, as shown by the trend analysis in this investigation. Overall, much more trends of improvement than of worsening have been observed; this is true for almost all the media and biological components studied, with the exception of phytoplankton; and it applies as well to almost all the stations and water bodies, with the exception of those corresponding to areas with water treatment pending of accomplishment. In estuaries with decreasing human pressures during the period, the percentage of series showing quality improvement was higher (approx. 30%) than those showing worsening of quality (12%). Moreover, in those water bodies showing an increase of pressure, variables which can be considered indicators of anthropogenic effects showed negative trends (quality worsening). On the other hand, some of the variables analysed were more affected by natural variability than by changes in pressures. That was the case of silicate, nitrate and suspended solids, which followed trends correlated to salinity, which, in turn, was related to the rainfall regime during the study period.
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