Local changes in the composition and community structure of suprabenthic peracarid crustaceans on the bathyal Mediterranean: influence of environmental factors

Deep-water assemblages of suprabenthic peracarids were analyzed in the SW Balearic Islands (Algerian Basin, southwestern Mediterranean) between 249 and 1,622 m depth; the patterns of species composition, possible zonation, and trophic structure found in this area were compared with those exhibited by peracarids in the mainland side of the Catalan Sea slope (northwestern Mediterranean). One hundred and four peracarid species (plus one leptostracan) were identified on the Balearic Islands slope, amphipods being the most diversified taxon (45 species). On the Balearic slope, two distinct depth assemblages were distinguished: one at the upper slope (US), between 249 and 402 m depth and the second at the deep slope, between 543 and 1,620 m depth. A remarkable species substitution occurred at depths between 402 and 638 m. In the Catalan Sea, in addition to the US assemblage occupying depths between 208 and 408 m, a second boundary of faunal change was found around 1,250 m. Suprabenthos biomass increased from 242 to approximately 500 m. Suprabenthos attained the highest biomass values (100 g wet weight/10,000 m²) at intermediate depths between 504 and 1,211 m, as also occurred with the associated zooplankton collected with suprabenthos (peak biomass between 502 m and 898 m). Suprabenthos biomass did not show any significant correlation with any environmental water-column variable. In contrast, zooplankton (especially small fish and decapod crustaceans) showed a significant positive correlation with fluorometry and turbidity at different levels of the water column. The feeding guilds of species showed important differences between the two areas only on the US, with a higher abundance of deposit feeders in the Catalan Sea (20.4%) than in the Balearic Islands (4.2%). The low contribution of deposit feeders in the SW Balearic Islands may ultimately be a consequence of the lack of river discharges in this area.Communicated by S.A. Poulet, Roscoff     

An assessment of microbial communities associated with surface mining-disturbed overburden

To assess the microbiological changes that occur during the maturation of overburden that has been disturbed by surface mining of coal, a surface mining-disturbed overburden unit in southeastern Ohio, USA was characterized. Overburden from the same unit that had been disturbed for 37 and 16 years were compared to undisturbed soil from the same region. Overburden and soil samples were collected as shallow subsurface cores from each subregion of the mined area (i.e., land 16 years and 37 years post-mining, and unmined land). Chemical and mineralogical characteristics of overburden samples were determined, as were microbial respiration rates. The composition of microbial communities associated with overburden and soil were determined using culture-independent, nucleic acid-based approaches. Chemical and mineralogical evaluation of overburden suggested that weathering of disturbed overburden gave rise to a setting with lower pH and more oxidized chemical constituents. Overburden-associated microbial biomass and respiration rates increased with time after overburden disturbance. Evaluation of 16S rRNA gene libraries that were produced by “next-generation” sequencing technology revealed that recently disturbed overburden contained an abundance of phylotypes attributable to sulfur-oxidizing Limnobacter spp., but with increasing time post-disturbance, overburden-associated microbial communities developed a structure similar to that of undisturbed soil, but retained characteristics of more recently disturbed overburden. Our results indicate that over time, the biogeochemical weathering of disturbed overburden leads to the development of geochemical conditions and microbial communities that approximate those of undisturbed soil, but that this transition is incomplete after 37 years of overburden maturation.     

Survey of the occurrence of pharmaceuticals in Spanish finished drinking waters

Fifty samples of finished drinking waters (FDWs) from Spain covering 12 million inhabitants were tested for 53 pharmaceuticals pertaining to 12 different Anatomical Therapeutic Chemical (ATC) classification system codes. The studied compounds are a combination of most commonly consumed pharmaceuticals with other barely reported in the literature. Five compounds, azithromycin, clarithromycin, erythromycin, sulfamethoxazole, and ibuprofen were tentatively identified by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) in some samples (2 to 15 %), but only ibuprofen and azithromycin could be confirmed when analyzed by liquid chromatography–high-resolution mass spectrometry (LC-HRMS) with a quadrupole-Orbitrap instrument. Concentration levels of ibuprofen in the positive samples ranged from 12 to 17 ng/L (n?=?6) while for azithromycin values from 5 to 9.5 ng/L (n?=?3) were found. Ibuprofen fragmentation behaviour in different mass spectrometry instrument configurations (triple quadrupole, quadrupole-ion trap, and quadrupole-Orbitrap) was evaluated.     

The effect of spent bleaching earth ageing process on its physicochemical and microbial composition and its potential use as a source of fatty acids and triterpenes

This study was aimed at investigating the physicochemical and microbiological changes that took place during the ageing process of spent bleaching earth in the presence of autochthonous microorganisms. Research material included fresh spent bleaching earth (SBE₀) and the same material after 3 years of storage at the constant temperature of 20 °C, without aeration and moistening (SBE₃). Changes in the chemical composition of analysed waste material were observed during its ageing process point to a spontaneous bioconversion of fat substance towards formation and/or release of free saturated fatty acids C16:0 and C18:0 (14.3 g 100 g^?1 D.M.), triterpenes (8.48 g 100 g^?1 D.M.), cholesterol (3.29 g 100 g^?1 D.M.), small quantities of carbohydrates and esters (0.80 g 100 g^?1 D.M.). This process was accompanied by other changes in physicochemical parameters of the waste material, such as colour, odour and viscosity, decrease in fat content from 28.27 to 24.6 % and that of soluble forms of metals (Mo, Cu, Fe, Zn, Ni, Cr and Mn), ranging from 25 to 75 %, and an increase in pH, from 3.85 to 4.2. At the same time, changes in the microbial consortium were observed.     

Edible Protein Energy Return on Investment Ratio (ep-EROI) for Spanish Seafood Products

Life cycle assessment (LCA) has developed into a useful methodology to assess energy consumption of fishing fleets and their derived seafood products, as well as the associated environmental burdens. In this study, however, the life cycle inventory data is used to provide a dimensionless ratio between energy inputs and the energy provided by the fish: the edible protein energy return on investment (ep-EROI). The main objective was to perform a critical comparison of seafood products landed in Galicia (NW Spain) in terms of ep-EROI. The combination of energy return on investment (EROI) with LCA, the latter having standardized mechanisms regarding data acquisition and system boundary delimitation, allowed a reduction of uncertainties in EROI estimations. Results allow a deeper understanding of the energy efficiency in the Galician fishing sector, showing that small pelagic species present the highest ep-EROI values if captured using specific fishing techniques. Finally, results are expected to provide useful guidelines for policy support in the EU’s Common Fisheries Policy.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-013-0426-2) contains supplementary material, which is available to authorized users.     

Study of metal fractionation in river sediments. A comparison between kinetic and sequential extraction procedures

The extraction kinetic of trace metals (Cd, Cu, Pb, and Zn) in river sediments by four extraction agents was studied. As extractants ammonium acetate, acetic acid, hydroxylamine and EDTA solutions were assayed. These reagents can leach the metals more or less selectively from several metal compartments of sediments. The metal leaching kinetic model permits classification of the metal species in labile and moderately-labile ones. The combination of two or more non specific reagents permits a high characterisation of metal distribution and leachability. The results obtained with this model in four river sediments were compared with data obtained by the SM&T sequential extraction procedure, in order to characterise the chemical nature of leached metal.     

Suitability of Scirpus maritimus for petroleum hydrocarbons remediation in a refinery environment

Purpose  

In the ambit of a project searching for appropriate biological approaches for recovering a refinery soil contaminated with petroleum hydrocarbons (PHC), we compared results obtained in the absence and in the presence of the salt marsh plant Scirpus maritimus or Juncus maritimus or an association of these two plants, which were tested in the refinery environment. Synergistic effects caused by addition of a non-ionic surfactant and/or a bioaugmentation product were also investigated. Major challenges of this study were: field conditions and weathered contamination.     

Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement

The effects of the herbicide atrazine on the gill of the freshwater fish Prochilodus lineatus were evaluated after exposure of fish to 2, 10 and 25 μg L⁻¹ atrazine during 48 h (acute exposure) and 14 d (subchronic exposure). Ions and osmolality were measured in plasma and gill samples were taken to determine the Na⁺/K⁺-ATPase (NKA) and carbonic anhydrase (CA) activities and for morphological analysis. Plasma osmolality and Na⁺ and Cl⁻ ions changed depending on atrazine concentration, but atrazine exposure had no effect on the Na⁺/Cl⁻ ratio. NKA activity did not change after atrazine exposure, but CA activity decreased in fish exposed to 25 μg L⁻¹ for 14 d. Gill MRC density decreased after acute exposure but did not change in fish exposed to the subchronic treatment. The MRC density at the epithelial surface increased in fish exposed to 25 μg L⁻¹, and the MRC fractional area (MRCFA) increased in fish exposed to 10 μg L⁻¹. The changes in MRCs provide evidence of morphological adjustments to maintain ionic homeostasis in spite of the inhibition of CA activity at the highest atrazine concentration.