Search

Sedimentological, paleobiological, mineralogical, and geochemical analyses of a sediment core retrieved on the seafront of Cartagena Bay were performed after high-resolution sampling. A wide series of dates obtained through radiocarbon and amino acid racemization proved that the Holocene record on the analyzed core began at ca. 7300 yr cal BP. Reinterpretation of the marine seismic profiles indicated that the beginning of this transgression was channeled along erosive paleochannels excavated on a coastal plain of, at least, MIS5c age. The Holocene paleoenvironmental evolution consisted of a first period marked by marine conditions with strong inputs from a fan delta linked to the reorganized fluvial network that occurred after the sudden rise of the base level, which caused a growing sedimentary prism. Later, the full marine environment was reflected in the development of a Posidonia - Cymodocea meadow hosting a rich biodiversity of marine species (mollusks, foraminifera, ostracoda). Around 3800 yr cal BP, the area underwent a profound change and a silting process started to alter the conditions, turning the area into a paucispecific brackish marsh environment in which mud deposition was dominant. Since Carthaginian times, arrangement works locally affected the record, allowing the arrival of some marine species due to port work (dredging) undertaken to gain depth and showing anthropic influence. [ABSTRACT FROM AUTHOR]

Meat consumption by early hominins is a hotly debated issue. A key question concerns their access to large mammal carcasses, including megafauna. Currently, the evidence of anthropic cut marks on proboscidean bones older than -or close to- 1.0 Ma are restricted to the archaeological sites of Dmanisi (Georgia), Olduvai (Tanzania), Gona (Ethiopia), Olorgesailie (Kenya) and La Boella (Spain). During an inspection of the almost complete carcass of Mammuthus meridionalis (FN3-5-MPS) from the Oldowan site of Fuente Nueva 3 (Orce, Spain, c. 1.2 Ma), a few traces compatible with human-made cut marks and carnivore tooth marks were found. From this finding and previous interpretations the following questions arise: When and under what conditions was FN3-5-MPS deposited? What is the nature of the marks found on the surface of the bones of this mammoth? To answer, we have conducted a high-resolution analysis of these remains, combining both taphonomic and microstratigraphic data. Our results, using microstratigraphic and micromorphological analyses of sediments based on thin-sections, show that this individual was deposited in a marshy environment. Subsequently, the carcass was exploited by hominins and large felids that left their marks on the surface of some of its bones. For this purpose, the identification and characterisation of both cut marks and tooth marks were performed using high-resolution 3D modelling, geometric morphometrics, and artificially intelligent algorithms. Based on the anatomical position of both the cut and tooth marks, we propose that both the hominins and the saber-toothed cats had early access to the animal. Finally, this paper shows how an interdisciplinary approach can shed detailed light on the particular story regarding the death and processing of the carcass of a female mammoth, deposited at Fuente Nueva 3. • Original contextual approach combining taphonomy and microstratigraphy. • Proboscidean found in FN3 (FN3-5-MPS) died in a watery environment. • Cut and tooth marks reveal proboscidean exploitation by felids and Homo. • Earliest evidence of cut marks on proboscideans bones in western Eurasia. • New insights into the behaviour of the first inhabitants of western Eurasia. [ABSTRACT FROM AUTHOR]

Sheep remains constitute the main archaeozoological evidence for the presence of Early Neolithic human groups in the highlands of the Southern Pyrenees but understanding the role of herding activities in the Neolithisation process of this mountain ecosystem calls for the analysis of large and well-dated faunal assemblages. Cova de Els Trocs (Bisaurri, Huesca, Spain), a cave located at 1564 m a.s.l on the southern slopes of the Central Pyrenees, is an excellent case study since it was seasonally occupied throughout the Neolithic (ca. 5312–2913 cal. BC) and more than 4000 caprine remains were recovered inside. The multi-proxy analytical approach here presented has allowed us to offer new data elaborating on vertical mobility practices and herd management dynamics as has not been attempted up until now within Neolithic high-mountain sites in the Iberian Peninsula. For the first time, δ18O and δ13C stable isotope analyses offer direct evidence on both the regular practice of altitudinal movements of sheep flocks and the extended breeding season of sheep. Autumn births are recorded from the second half of the fifth millennium cal. BC onwards. Age-at-death distributions illustrate the progressive decline in caprine perinatal mortality together with the rising survival rate of individuals older than six months of age and the larger frequency of adults. This trend alongside the 'off-season' lambing signal at the implementation of husbandry techniques over time, probably aiming to increase the size of the flocks and their productivity. Palaeoparasitological analyses of sediment samples document also the growing reliance on herding activities of the human groups visiting the Els Trocs cave throughout the Neolithic sequence. In sum, our work provides substantial arguments to conclude that the advanced herding management skills of the Early Neolithic communities arriving in Iberia facilitated the anthropisation process of the subalpine areas of the Central Pyrenees. [ABSTRACT FROM AUTHOR]

A rapid solid-spiking matrix-matched strategy is applied to simultaneously determine Cd and Cr in sediments by laser ablation inductively coupled plasma isotope dilution mass spectrometry (LA-ICP-IDMS). For this, conventional instrumentation (i.e. nanosecond laser device and ablation chamber) frequently available in laboratories is used. Two drying procedures for the synthesis of the isotopically enriched solid spike were studied considering precision, as RSD values, and applying nested ANOVA statistics; where from it was found that rotary evaporation mixed the spike solution with the solid matrix best. Thus, the solid spike is prepared using a drying step which reduced significantly the time of the synthesis, from hours (reported in literature) to minutes. The elemental distribution of the target isotopes in the pellets was assessed for natural isotope composition materials, solid spikes and enriched blend samples, and it was statistically demonstrated that the ablation of only five lines per pellet provided satisfactory precision. The time of the measurement step of the mass spectrometer was reduced compared to conventional instrumental conditions, programming a unique sequence to measure Cd (in low mass resolution) and Cr (in medium mass resolution) in the same ablation line. The study of the variables affecting the ablation process by means of a Plackett–Burman experimental design revealed that the method was robust. Accuracy was studied, both trueness (experimental/certified values ratios around unity) and precision (relative standard deviations around 2% and 4% for Cd, and 7% and 10% for Cr, when analyzing SRM 1944 and PACS-3, respectively), with good results. Satisfactory relative uncertainties in the range 10–17% were obtained. The important task of the applicability of the proposed approach (not often found in the literature) was demonstrated by the analysis of marine sediments collected at the Northwest coast of Spain. [ABSTRACT FROM AUTHOR]

Galician rías provide several ecosystem services of great ecological and economic significance in the northwestern Iberian margin, requiring a good environmental quality for sustainable harnessing. More paleoenvironmental reconstructions extending to their preindustrial state are needed to predict their evolution under natural and human-induced perturbations, such as ongoing anthropogenic global warming. This study's aim is twofold: first, characterize the current environmental conditions governing the inner Ría of Ferrol (Galicia, NW Spain) and address its recent natural and anthropogenic evolution. Therefore, a multiproxy approach (benthic foraminifera, grain size, pollen content, trace metals, Al, total organic and inorganic carbon contents, total nitrogen content, δ13C, magnetic susceptibility, 210Pb and 137Cs radiotracers, and microplastics) has been applied to intertidal surface and sediment core samples. The benthic foraminiferal results exhibit typical inner ría assemblages, primarily driven by natural ría-estuarine dynamics, with a higher dominance of brackish species (H. germanica , A. morphogroup tepida), fewer living individuals and marine allochthonous taxa toward the continental end-member. The foraminiferal standing crops and surface trace metal concentrations do not reflect strong anthropogenic impacts, although areas with elevated magnetic susceptibility have been detected, probably associated with nearby industrial activities. The recent sedimentary deposits reveal anthropogenic impacts at local and regional scales, with different environmental shifts. Local impacts were triggered by physical interventions in the inner ría, with the construction of the As Pías Bridge in 1968 and the great urban-industrial development of Ferrol city and surrounding localities experienced since the late 19th century. Land-use changes have driven regional scale changes, corresponding to reforestation plans with the introduction of anthropogenic plant species for industrial purposes initiated in the 1940s. The stratigraphic analysis of sediment cores has unveiled high levels of contaminants (Zn and microplastics) in the innermost sector as the primary environmental concerns. In this sediment-infilling and restricted area, potential dredging activities could release them leading to their possible bioavailability. Although past adverse environmental conditions cannot be discarded, sedimentary intervals with negligible presence of microfauna in the innermost area have mostly been attributed to taphonomic processes involving calcareous dissolution and disaggregation of agglutinated tests, likely caused by carbonate-undersaturated conditions and organic matter metabolization by microbial activity respectively. • Inner ría sediments allow a precise (paleo)environmental reconstruction. • The overall current environmental state of the inner ría is good. • Historical environmental shifts at local and regional scales have been detected. • Zn and microplastics, main contaminants, could be made bioavailable after dredging. • Azoic intervals resulted from taphonomic biases, not only from anthropogenic impacts. [ABSTRACT FROM AUTHOR]

Gallocanta Lake (NE Spain), with a high ecological value, is the largest and best preserved saline lake in Western Europe. The aim of this study is to map the landforms developed in the margins of the central sector of Gallocanta Lake, at adequate scale for the study of soils and habitats, which is needed for the delineation, management and protection of the wetland. Photointerpretation was combined with topographical, geological, and satellite data in a geographical information system. This study, applied in two selected areas of the central body of the lake, allowed the identification of contrasting landforms and processes in the lake margins. The southern margin, which receives most of the fluvial materials in the zone exhibits coastal progradation by means of barrier-island generation and sedimentation in the resulting coastal lagoon, a process that can be inferred from the map presented in this work and was confirmed by comparison of aerial photographs taken in different decades. With virtually no sediment supply on the margin, coastal erosion and shoreline retreat prevail. In summary, coastal landforms are a result of a complex combination of fluvial and lacustrine processes operating during high and low water-level periods. [ABSTRACT FROM AUTHOR]

Abstract: Endorheic basins located in semiarid or arid regions constitute one of the most vulnerable and exposed environments to pollution. The Pétrola basin (Central Spain) is an outstanding example of one of these endorheic system. Several constraints have been observed that impede correct identification of the denitrification pathway and its degree at the field scale. To better understand the key factors controlling attenuation, a five-stage column experiment was performed using organic and pyrite rich sediments from the Utrillas Facies (Lower Cretaceous) as a possible electron donor source to promote denitrification. A chemical and multi-isotopic characterization (δ15NNO3, δ18ONO3, δ13CDIC, δ34SSO4, δ18OSO4) of the outflow of the column experiment showed that attenuation was driven by organic matter. The amount of organic C consumed during denitrification was 2% of the total organic C present in the sediment. Both the degree and rate of denitrification were related to flow rate variations. Lower flow rates favored bacterial growth at the beginning of the experiment producing an increase of complete denitrification rate (CDR). When reduction was greater than 15%, CDR remained constant (around 30μmolL−1 d−1) under different flow rates. In the last stage, flow rate had no effect on output concentration because the organic C supply was limited and had become the main kinetic factor in denitrification. Isotopic fractionations (ε of 15N– and 18O– between reaction products and remaining reactants were calculated using representative column samples. The results for the two attenuation stages observed were −11.6‰ and −15.7‰ for εN, and −12.1‰ and −13.8‰ for εO. Most of the field samples showed a percentage of attenuation ranging from 0% to 60% of removal. [Copyright &y& Elsevier]

Abstract: This study evaluates the feasibility of comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC–ToF MS) for the determination of the 15+1EU PAHs in sediments. Experimental variables affecting the injection, chromatographic separation and analytical detection of the analytes have systematically been optimised. Under finally proposed conditions, a satisfactory resolution among critical pairs/groups of PAHs, including benz[a]anthracene, cyclopenta[cd]pyrene and chrysene, the three benzofluoranthene isomers, indeno[1,2,3-cd]pyrene from dibenz[a,h]anthracene (DahA), and DahA from dibenz[a,c]anthracene, has been achieved using DB-5×BPX-50 as column combination with a run time of 1h. The feasibility of the method for the analysis of real-life samples has been demonstrated by accurate determination of relevant target PAHs in the certified harbour sediment BCR-535 (deviations among certified concentration values and those calculated using the proposed method lower than 3%); and by successful application to sediments sampled from a relevant protected area located in the South of Spain. The low methodological limits of detection (LODs) obtained for most of the targeted PAHs (in the 5.7–60μg/kg range, as calculated for real samples) guarantied accurate quantification of the target compounds at the low levels expected in these types of pristine matrices. The strong retention experienced by the heaviest dibenzopyrene isomers included in the study resulted in relatively high LODs for these analytes; nevertheless, these compounds were detected at concentration levels above the corresponding LOD in some of the analysed sediments. In addition, the enhanced identification power provided by GC×GC–ToF MS for the identification of non-target analytes allowed the tentative identification of a group of polynuclear aromatic thiophenes in some of the test samples. Finally, the potential of the use of normalised bubble plots for the fast screening of the potential PAH sources has been demonstrated. [Copyright &y& Elsevier]

In the Rodalquilar mining district of SE Spain, a total of 46 soil samples that were between 0 and 20 cm in depth were taken from the tailings dump, stream sediments, and surfaces that were presumably were unaffected by mining. In each soil sample, organic carbon content, pH, particle size distribution and total and soluble trace element content were analysed. Pollutants were scattered by runoff from two source areas: tailings from Au mining (Sn, Sb, As and Se) and wastes from Pb mining (Pb, Cu and Zn). Sn, Pb, and Sb were spread mostly in the solid phase of the runoff, while Cu, Zn, As and Se were spread in both the solid and soluble phases of the runoff. The pollutants with the highest soluble concentrations were As and Se, which were scattered at greater distances from the source. Some evidence suggests that tailings from Au mining could also be scattered by wind, but no farther than 1500 m from the source. [Copyright &y& Elsevier]

Abstract: The subtidal sediments of the inner Ría de Vigo (NW Spain) are fine-grained, rich in organic matter, and accumulate at rates of around 3 mm/yr. Redoxomorphic pyrites formation was studied in four sediment cores. Four operationally-defined iron fractions were determined (HCl-extracted, silicate-bound, organic and pyritic), and the dimensions and morphology of pyrites (which mainly occurred as isolated framboids 3–5 μm in diameter) were studied by SEM. Sediment appearance and degree of pyritization (DOP) identified an oxic zone limited to the top few millimetres, a suboxic zone that in most cores was just a few decimetres thick (the exception was a core obtained in an area of strong turbulent currents), and an underlying anoxic zone with DOP values of around 60%. Pyritic iron increased at the expense of the HCl-extracted fraction in approximately the top metre, but no further pyrite formation occurred at greater depths. Pyrite formation in these lower levels was not limited by lack of either HCl-extracted iron or metabolizable organic matter, but apparently by lack of sulphate ion, the diffusion of which to these depths was probably prevented by the fine texture of the sediments. Our findings highlight the interest of studying transitional sedimentary environments in order to explore in detail the geochemical parameters controlling pyrite formation. [Copyright &y& Elsevier]

Settling particles were collected by an array of sediment trap moorings deployed along the Cap de Creus (CCC) and Lacaze-Duthiers (LDC) submarine canyons and on the adjacent southern open slope (SOS) between October 2005 and October 2006. This array collected particles during common settling processes and particles transferred to deep waters by dense shelf water cascading (DSWC). Polychlorobiphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlorobenzenes (CBzs)—pentachlorobenzene and hexachlorobenzene—and hexachlorocyclohexanes were analyzed in all samples. The results show much higher settling fluxes of these compounds during DSWC than during common sedimentation processes. The area of highest deposition was located between 1000 and 1500 m depth and extended along the canyons and outside them showing their channelling effects but also overflows of dense shelf water from these canyons. Higher fluxes were observed near the bottom (30 m above bottom; mab) than at intermediate waters (500 mab) which is consistent with the formation and sinking of dense water close to the continental shelf and main displacement through the slope by the bottom. DSWC involved the highest settling fluxes of these compounds ever described in marine continental slopes and pelagic areas, e.g., peak values of PCBs (960 ng·m-2·d-1), DDTs (2900 ng·m-2·d-1), CBzs (340 ng·m-2·d-1) and lindane (180 ng·m-2·d-1). [ABSTRACT FROM AUTHOR]

Abstract: This article proposes a synthetic model to explain the cracking process observed in Santos Morcillo Lake, Ruidera Lakes Natural Park, central Spain. The model was obtained by means of a comprehensive review of the available data, supplemented with an electrical tomography survey and a field and laboratory investigation. The system’s structure has been condensed into a microscale model based on a sediment column connecting the crust of the lake bottom with the Mesozoic substrate. The deformation of both this column and the crust covering it allows for a consistent explanation of the behaviors observed. It also provides a simple reproduction of the crack opening data. Hence the model has been used to define guidelines for the safe use and management of this protected space. [Copyright &y& Elsevier]

Changes in benthic community structure are strongly related to environmental factors, and we need to determine how these natural changes occur in order to interpret the possible changes associated with anthropogenic impacts. The aim of this survey was to characterize and classify the polychaete assemblages inhabiting unpolluted soft bottoms in the Spanish Mediterranean in relation to environmental factors. Thirteen localities were sampled at depths between 9 and 31 m, from 2004 to 2006. Multivariate techniques showed that the structure of polychaete assemblages detected in 2004 was consistent over time and correlations between polychaetes and environmental factors were detected. The study area comprises four kinds of communities mainly characterized by polychaete assemblages, sediment types, and depth. [ABSTRACT FROM AUTHOR]

Abstract: The present paper deals with the application of Tucker3 modelling to a sediment monitoring data set from the area of Mar Menor coastal lagoon (Spain). The aim of the study is to model and interpret the fractionation of heavy metals in the suspended particulate matter and sediment fractions resulting by sedimentation processes. Since the lagoon is seriously influenced by anthropogenic activities the modelling aims an assessment of the environmental hazard, too. After application of various scaling and centering procedures and estimation of the model dimensionality, an optimal (3, 3, 3) Tucker3 model was chosen for data interpretation. Using the model output (factor loadings connected to the four main core elements) it could be concluded that the heavy metal concentrations in the suspended particulate matter and sediment fractions increase in order Cu>Mn>Zn≈Pb>Cd and could be examined as estimation of basic levels for all heavy metals caused by different sedimentation processes. The second important core element summarizes the anthropogenic influence of the mining activity in the region. The third important core element shows the different mobility of the heavy metals. The fourth important core element should be related to the specific sediment formation at one of the sampling location. [Copyright &y& Elsevier]

Abstract: Coastal outcrops of Upper Pleistocene deposits in north-eastern Mallorca (Balearic Islands, Spain) have been examined and a chronological framework established using Optically Stimulated Luminescence (OSL) dating. The outcrops record a complex interaction between aeolian, colluvial and alluvial fan deposition that result in a variable stratigraphical architecture. Dating and facies analysis make it possible to identify four aeolian activity episodes during MIS 5c/b, 4 and 3, and also add to the understanding of the environmental history of north-eastern Mallorca over the last 100 ka. The new data suggest enhanced aeolian transport and dune formation during cold climatic intervals when sea level was low, sediment supply (exposed marine carbonate sediment) was high, winter windiness was high, and vegetation on coastal plains at a minimum. [Copyright &y& Elsevier]

Abstract: The multi-proxy analysis of sediment cores recovered in karstic Lake Estanya (42°02′ N, 0°32′ E; 670m a. s. l., NE Spain), located in the transitional area between the humid Pyrenees and the semi-arid Central Ebro Basin, provides the first high-resolution, continuous sedimentary record in the region, extending back the last 21 000 years. The integration of sedimentary facies, elemental and isotopical geochemistry and biogenic silica, together with a robust age model based on 17 AMS radiocarbon dates, enables precise reconstruction of the main hydrological and environmental changes in the region during the last deglaciation. Arid conditions, represented by shallow lake levels, predominantly saline waters and reduced organic productivity occurred throughout the last glacial maximum (21–18calkyrs BP) and the lateglacial, reaching their maximum intensity during the period 18–14.5calkyrs BP (including Heinrich event 1) and the Younger Dryas (12.9–11.6calkyrs BP). Less saline conditions characterized the 14.5–12.6calkyrs BP period, suggesting higher effective moisture during the Bölling/Allerød. The onset of more humid conditions started at 9.4calkyrs, indicating a delayed hydrological response to the onset of the Holocene which is also documented in several sites of the Mediterranean Basin. Higher, although fluctuating, Holocene lake levels were punctuated by a mid Holocene arid period between 4.8 and 4.0calkyrs BP. A major lake-level rise occurred at 1.2calkyrs BP, conducive to the establishment of conditions similar to the present and interrupted by a last major water level drop, occurring around 800calyrs BP, which coincides with the Medieval Climate Anomaly. The main hydrological stages in Lake Estanya are in phase with most Western Mediterranean and North Atlantic continental and marine records, but our results also show similarities with other Iberian and northern African reconstructions, emphasizing peculiarities of palaeohydrological evolution of the Iberian Peninsula during the last deglaciation. [Copyright &y& Elsevier]

Abstract: Biomass, primary production and nutrient budgets associated to Sarcocornia perennis subspecies (ssp.) alpini were studied in the Palmones River estuary salt marsh (Southern Spain) to evaluate the nutrient sequestration capacity of the low marsh. Above- and belowground living and dead biomass, as well as carbon, nitrogen and phosphorus content were monitored during 1 year. Additionally, the fate of aboveground detritus was evaluated in an experiment on litter decomposition. The detritus production of S. perennis ssp. alpini was almost equivalent to its annual primary production indicating a rapid turnover of biomass. We calculated that only 12% of the aboveground detritus was exported out of the low marsh while the rest was decomposed in the sediment with a rate of 0.8year−1. Changes in concentrations of total carbon, nitrogen and phosphorus in the sediment showed patterns related to S. perennis ssp. alpini belowground biomass. Our results suggested that the sediment functions as a net sink for nutrients accumulating 550gCm−2 year−1, 55gNm−2 year−1, and 13gPm−2 year−1. [Copyright &y& Elsevier]

Abstract: Production (P) and production/biomass ratio (P/B) were estimated from 21 species of peracarid and eucarid crustaceans belonging to two different compartments (infauna: 10 species and suprabenthos: 11 species) using the Hynes size–frequency method. Calculations were based on 7 cruises performed between December 2002 and November 2003 in the continental shelf of the Ebro river delta (ED, Catalan Sea: northwestern Mediterranean). Within ED, P and P/B were compared between two neighbouring sites, one located on 47 m (S1), the other at 61 m (S2). The possible effects of natural variability on production were considered. Sediments in ED were muddy (%clay between 40 and 65%). No significant trend in production comparing S1 and S2 was detected, with 50% of species showing higher P value in S1, and 50% in S2. A significant trend emerged from P/B estimates, with 18 of 21 species showing higher P/B at S1. Similarly significant trends for infauna and suprabenthos were found after analyzing both compartments separately. It is suggested that the more significant P/B found on S1 both among infauna and suprabenthos could be caused by the higher temperature and organic matter content (%TOC) at S1. In multi-linear regression (MLR) models, differences in P between S1 and S2 were greater with increasing differences in the density of species (RD) between sites. Differences were greater in infauna than in suprabenthos, and greater among rare species (those with low dominance, %D). P/B differences between S1 and S2 were mainly explained by %D and RD, and to a lesser extent by differences between sites in the mean size of species (RW). In other words changes in P and P/B were not explained by removal of large size specimens. Some trawling activity occurred at S2, and it may alter the habitat of small macrofauna. In addition to natural variability, we discussed the possible influence of trawling disturbance on P and P/B, bearing in mind the feeding type, mobility, and dispersal capability of species. We suggest that amphipods of the genus Ampelisca, showing higher P/B on S1, characterized by low mobility (probably tube-dwellers), low trophic level (e.g. filter feeding strategies) and low dispersal capability (not free larvae), could be especially vulnerable to trawling impact. [Copyright &y& Elsevier]

Abstract: Caged, transplanted, intermoult, female shore crabs (Carcinus maenas) were exposed to sediments from the Port of Cadiz (SW, Spain); the Port of Huelva (SW, Spain), the Port of Pasajes (NE, Spain) and the Port of Bilbao (NW, Spain) for a period of 28days. Organisms were sampled on days 0, 7, 14, 21 and 28 allowing examination of different biomarkers to exposure to metals and organic compounds; metallothioneins (MTs), ethoxyresorufin O-deethylase (EROD), glutathione-S-transferase (GST) and glutathione peroxidase (GPX). Sediment samples were also analyzed to determine chemical concentration of metals (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb and Zn), PAHs and PCBs. Metals such as As, Cu and Zn associated with mining activities (Port of Huelva), and contaminants such as Ni, Pb, Hg and PCBs, associated with oil spills and industrial activities (Ports of Cadiz, Pasajes and Bilbao), were found to interfere in detoxification and/or anti-stress oxidative defenses in C. maenas. Positive, significant (p <0.05) induction of MTs concentration was associated with increasing sediment As, Cu, Zn and Hg concentrations. EROD activity was associated with PCBs, GST activity with Hg and GPX activity with As, Cu, Ni, Pb and Zn. The use of the parameter AR, which involves the kinetic patterns of the battery of biomarkers tested, was found to be a powerful and sensitive tool for evaluating the bioavailability and adverse effects of contaminants bound to sediments, enabling polluted and nonpolluted sites to be easily distinguished. [Copyright &y& Elsevier]

Abstract: The analysis of the lithofacies preserved in recent marine sediments in Cadiz Bay, shows major fluctuations in the depositional regime, which are characterized by significant energy variations. Drilling and geophysical data indicate the presence of coarse materials such as gravel, imbricated shells and plant remains, and frequent flow structures which have been interpreted as a result of the action of high energy events, while the finest sediments present in the cores are interpreted as a consequence of the ordinary depositional regime, fundamentally controlled by normal storm surge and tidal currents. Three types of sequence are differentiated: Very High Energy (VHE) sequences, High Energy (HE) sequences and Low Energy (LE) sequences. The VHE and HE sequences were caused by highly energetic oceanic agents such as great waves generated by major storms or tsunamis. There is no historical evidence of the action of sufficiently energetic storms, while the geological setting of Cadiz Bay is located near the Azores–Gibraltar fault, the limit between the African and European plates, points to tsunami action as being the most plausible option to explain the origin of these deposits. The radiocarbon age indicates that these high energy events happened between 898±120 BC and 849±121 AD, some of which coincide with several historically documented tsunamis affecting the Cadiz coast. This data indicates that the period from 849 AD to 1200 AD was a time of intense seismic and tsunamigenic activity. [Copyright &y& Elsevier]

Abstract: A research programme has been set up at Higueral de Valleja Cave in southern Spain to investigate the late survival and eventual extinction of the southern Iberian Neanderthals and the arrival of modern humans. Of key interest in the first phase of research was to understand the depositional environment in the entrance chamber of the cave and to establish whether palaeoenvironmental and dating samples could be retrieved from the Middle and Upper Palaeolithic sequences. The outcome is a series of OSL, TL and radiocarbon dates showing that the cave was occupied by Neanderthal populations in Marine Isotope Stage (MIS) 3, if not earlier, and by modern human Solutrean populations during the last glacial maximum. Cave sediments provisionally indicate that the lower Middle Palaeolithic sequence (X–VIII) formed in warm and humid environments and the upper sequence (VIII–V) formed when the climate was cooler and drier. The presence of long grass phytoliths and of the small mammals Microtus duodecimcostatus, Microtus brecciensis and Apodemus sylvaticus in the upper sequence indicates that a range of habitat types persisted near the cave including grassland, scrubby vegetation, patchy tree cover and ponds. This raises the possibility that environmental factors were key factors in the late survival of Neanderthal populations at the cave. [Copyright &y& Elsevier]

Along 10 campaigns, from June 2002 to September 2004, the concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were measured in sediments and oysters (Crassostrea sp.) taken from four sites in the Unesco protected natural reserve of Urdaibai (Basque Country, Bay of Biscay). Total PAH concentration ranged from 0.7 to 140μgkg−1 (dw) in the case of sediments, and from 300 to 1400μgkg−1 (dw) in the case of oysters. During this study, the coast of the Bay of Biscay was severely affected by the Prestige oil spill (November 2002). Presumably, as a consequence of this accident, both spatial and temporal variations of the PAHs, as well as the sources of the PAHs were affected by the oil spill, and this effect was observed in the total concentrations and, especially, in several diagnostic ratios and in multivariate data analysis. Finally, both BAF (bioaccumulation factor) and BSAF (biota-sediment accumulation factor) parameters were calculated to conclude that particulate matter seems to be the most favourable uptake pathway of PAHs in oysters from this estuary. [Copyright &y& Elsevier]

This article proposes a method for the thermogravimetric analysis (TGA) of marine sediment suspected of pollution by heavy metals, which may be appropriate for a selected region where the regression equations relating W2 weight loss as the independent variable and estimated metal abundance as the dependent variable have already been derived. Automated TGA may then be employed as a reconnaissance tool, to give a rapid and inexpensive predictive index of quality. The method has been applied to actual samples of known heavy metal content and the results have been compared with the quality criteria for dredged sediment proposed by the USEPA and other standards. These criteria have been translated into the corresponding classification categories provided by the TGA method. The sediment samples, on which thermal analysis from 50 to 900°C was performed, are from the southwest of Spain and several showed high levels of pollution. The first derivative of TG curves (DTG) and the chemical parameters analyzed were compared and those that provide better Pearson's coefficients were fitted by linear regression. From these fits several linear regression equations were proposed and taken as the basis for transforming the metal content values proposed in the USEPA and other international regulations in the form of TG data; finally, the method were validated by a certified material (MESS-3). [ABSTRACT FROM AUTHOR]

Abstract: Members of the INTERSED network initiated several efforts to coordinate management activities, information, priorities and approaches in research and technological development (RTD) with respect to sediments at a national level in Spain. The present work summarizes the results of a database search (1995–2005) carried out within the INTERSED framework; we found 250 international and national publications of Spanish groups related to the study of sediments located in the Spanish coast and river basins using different approaches. The results show the statistics of RTD groups involved, the main objectives of the publications, the types of sediment and their location, and the analytical method and parameters. We describe the state of the art on the field of research in sediments at the national level in Spain over a period of 10 years. [Copyright &y& Elsevier]

Spatial and temporal variations in the distribution of the grain-size characteristics of surficial sediments were studied and the areas susceptible to contamination associated with fine-grained sediments were identified in Cullera Bay, Spain. We analyzed 90 sediment samples collected during six sampling campaigns in July (mid-summer), September (end of summer) and November (mid-autumn) 2002, and February (mid-winter), April (mid-spring) and July 2003. Different methods of grain-size analysis (bivariant analysis and discriminant functions) were applied to interpret the environments and mechanisms of sediment deposition. To identify zones that showed greater susceptibility to contamination by toxic substances associated with fine-grain sizes, contour maps of sediment distribution were prepared for the six sampling campaigns. The surficial sediments at Cullera Bay were classified according to the deposition scenario into shallow marine deposits and fluvial sediment deposits associated with the Júcar River discharge. The spatiotemporal variation showed that coarse sediments concentrated in the area nearest to the river mouth, whereas the finest sediments concentrated in the central and northern areas of the bay during the dry season, making them susceptible to contamination by harmful substances associated with the fine-grained fraction. [ABSTRACT FROM AUTHOR]

Fish and sediments from four places along the Spanish River Cinca were analyzed for polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD). The samples were collected up- and downstream from MonzOn, a heavily industrialized town draining to the river. PBDEs and HBCD were found in sediments at levels ranging from 2 to 42 ng/g dry weight and from not detected (nd) to 514 ng/g dry weight respectively. Twenty-three fish samples (Barbus graellsi) collected at the same places were also analyzed, showing levels from rid to 446 ng/g wet weight for PBDEs and from nd to 1172 ng/g wet weight for HBCD. The lowest values for both sediment and fish samples were found upstream of the industry. Of 40 congeners (from mono- to deca-BDEs) included in the analytical work, 8 PBDE congeners were detected in river sediments, whereas 17 different PBDEs were found in fish samples. Large fish-to- sediment ratios for these brominated compounds indicate that they are highly bioavailable, with the exception of deca- BOE which was only detected in sediment samples. Concentrations of PBDEs and HBCD were slightly higher in muscle tissues than in liver samples obtained from the same specimen of fish. Moreover, PBDE and HBCD concentrations are correlated with fish length indicating the bioaccumulation of these contaminants. [ABSTRACT FROM AUTHOR]

The latest version (1999) of the BCR-sequential extraction technique was used to determine the distribution of metals (Cu, Zn, Cd, Pb, Fe, Ni, Cr, and Mn) with major sedimentary phases (acid-soluble, reducible, oxidisable and residual) in samples from the southwest coast of Spain. The total metal content was also determined. The results showed that an extensive area along the coast (35 km long), near the joint mouth of the Tinto and Odiel Rivers, contains sediments with high concentrations of metals, with maximums of 649 mg/kg of Zn, 336 mg/kg of Cu, 197 mg/kg of Pb and 2.5 mg/kg of Cd. The values found for Cr, Ni and Mn are comparable to those in unpolluted areas. Based on the chemical distribution of metals, we found that Zn is the most mobile (i.e., it can pass easily into the water under changing environmental conditions). This metal showed the highest percentages in the acid-soluble fraction (the most labile), especially in the central coastal area, where the samples contained over 50% of this element associated with this fraction. This area close to the Tinto and Odiel river mouths also shows a significant increase in the mobility of Cd and Cu. In both cases the amount present in the residual fraction is lower, and the acid-soluble fraction is increased for Cd and the oxidisable fraction for Cu. However, the highest percentages of Fe, Cr and Ni are found in the residual fraction (84%, 89% and 75%, respectively), which implies that these metals are strongly bound to the sediments. [Copyright &y& Elsevier]

A method based on selective pressurized liquid extraction (SPLE) followed by gas chromatography–negative ion chemical ionization-mass spectrometry (GC–NCI-MS) has been evaluated for analysis of decabromodiphenyl ether (PBDE-209) in sediment samples. Instrumental operating conditions such as source temperature and system pressure were optimized in the NCI-MS system, giving an instrumental detection limit of 2 pg. The limit of determination of the entire SPLE–GC–NCI-MS procedure was around 50 pg g-1 dry weight (dw), with repeatability of replicates between 4 and 21% relative standard deviation. Application of the method to 13 different river and marine sediment samples collected in Spain revealed that levels of decabromodiphenyl ether ranged between 2 and 132 ng g-1 dry weight. [ABSTRACT FROM AUTHOR]

• Optimization of FUSE-SPE-SBSE-TD-GC-MS/MS for booster biocides in marine sediment. • The use of SBSE for the pre-concentration of booster biocides in marine sediment. • The use of FUSE for the extraction of booster biocides in marine sediment. • Validation of FUSE-SPE-SBSE-TD-GC-MS/MS for booster biocides in marine sediment. Booster biocides present in natural waters may be captured by the sediments. Highly sensitive, robust, selective and reliable analytical methods are required to evaluate their presence in the sediments. A focused ultrasound assisted extraction method for the simultaneous determination of five organic booster biocides (Chlorothalonil, Dichlofluanid, Sea-Nine 211, Irgarol 1051 and TCMTB) in marine sediments is proposed. The isolation of the target compounds from 0.5 g of sediment was efficient using 2.5 mL of methanol as solvent, an output amplitude of 50 W, 100% duty cycle and an extraction time of 300 s. The extraction procedure was followed by solid-phase clean-up on non-polar sorbents (Oasis HLB). The compounds were sampled using stir bars (20 mm length, 0.5 mm film thickness) coated with polydimethylsiloxane (PDMS). The stir bars were stirred at 900 rpm for 3 h at room temperature. Desorption was carried out by thermal desorption (TD), and the analytes were separated in the gas chromatography (GC). They were detected by triple quadrupole mass spectrometry (MS/MS) using the multiple reaction monitor (MRM) mode. The detection limits (DLs) of booster biocides were in the range of 0.02 to 2.2 ng g −1 dry weight. The regression coefficients were higher than 0.999. The average recovery was higher than 86% (R.S.D.: 7–11%). The analytical procedure was applied to determination of the booster biocides in port sediment samples from the southwestern Spain. Sea-Nine 211 was found in one sediment at a level of 2.1 ng g−1. Irgarol was present in all the sediments at concentrations between 2 and 9 ng g−1. Image, graphical abstract [ABSTRACT FROM AUTHOR]