Effects of middle-term land reclamation on nickel soil-water interaction: a case study from reclaimed salt marshes of Po River Delta,Italy

Reclaimed salt marshes are fragile environments where water salinization and accumulation of heavy metals can easily occur. This type of environment constitutes a large part of the Po River Delta (Italy), where intensive agricultural activities take place. Given the higher Ni background of Po River Delta soils and its water-soluble nature, the main aim of this contribution is to understand if reclamation can influence the Ni behavior over time. In this study, we investigated the geochemical features of 40 soils sampled in two different localities from the Po River Delta with different reclamation ages. Samples of salt marsh soils reclaimed in 1964 were taken from Valle del Mezzano while soils reclaimed in 1872 were taken nearby Codigoro town. Batch solubility tests and consecutive determination of Ni in pore-water were compared to bulk physicochemical compositions of soils. Bulk Ni content of the studied soils is naturally high, since these soils originated from Po River sediments derived from the erosion of ultramafic rocks. Moreover, it seems that Ni concentration increases during soil evolution, being probably related to the degradation of serpentine. Instead, the water-soluble Ni measured in the leaching tests is greater in soils recently reclaimed compared to the oldest soils. Soil properties of two soil profiles from a reclaimed wetland area were examined to determine soil evolution over one century. Following reclamation, pedogenic processes of the superficial horizons resulted in organic matter mineralization, pH buffer, and a decrease of Ni water solubility from recently to evolved reclaimed soil.     

Numerical modeling as a tool for evaluating the renewability of geothermal resources: the case study of the Euganean Geothermal System (NE Italy)

Environmental Geochemistry and Health - Renewable natural resources are strategic for reducing greenhouse gas emissions and the human footprint. The renewability of these resources is a crucial...     

Bioremediation of aquaculture wastewater from Mugil cephalus (Linnaeus, 1758) with different microalgae species

Current aquaculture practices have a detrimental impact on the environment, in particular due to the release of high concentration of nitrogen and phosphorus that can induce eutrophication. This study investigates and compares the capacity of three microalgae species Tetraselmis suecica, Isochrysis galbana and Dunaliella tertiolecta, in the bioremediation of grey mullet Mugil cephalus wastewater. The experiment was conducted in batch conditions for 7 days using completely mixed bubble column photobioreactors. After two days, T. suecica and D. tertiolecta were able to remove more than 90% of dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorous (DIP), whereas I. galbana removed only 32% and 79% of DIN and DIP, respectively. A higher biomass yield resulted for T. suecica (603?±?34?mg/L, mean?±?SE). This study confirms the potential to employ T. suecica in an Integrated Multi-Trophic Aquaculture system for bioremediation of wastewater and identifies D. tertiolecta as another valid candidate species. Moreover, these species can growth in unsterilized culture media, and this reduces energy consumption, costs and efforts.     

Prenatal diagnosis of a mosaic supernumerary marker iso (8p) (tetrasomy 8p): discordance between chorionic villi culture and amniotic fluid karyotypes

We describe the first case of mosaic supernumerary marker iso (8p) displaying a karyotype discordance between chorionic villi (CV) and amniotic fluid (AF) cultures during prenatal cytogenetic diagnosis. In the first trimester, cytogenetic analysis after chorionic villi sampling (CVS) was normal in all metaphases in the short-term cytotrophoblast cell culture, but an undefined supernumerary marker was detected in 60% of mesenchymal cells in the long-term CV culture. Informed of the mosaicism, the couple selected amniotic fluid sampling as a second-trimester confirmatory diagnostic procedure. The supernumerary marker was absent in all of the 25 available AF cells metaphases. The prospective parents received genetic counselling and were informed that the discordance could be interpreted as a placental confined mosaicism or as a true foetal mosaicism with low percentage of affected cells. The couple opted to continue the pregnancy. In the second month of life, the child had abnormal development with severe psychomotor delay and frequent episodes of epilepsy. Postnatal cytogenetic extensive re-evaluation discovered that the previously detected supernumerary marker was indeed an isochromosome (8p) rearrangement present at low frequency in 5% of the blood lymphocytes. Copyright © 2006 John Wiley & Sons, Ltd.     

An alternative way to determine the size distribution of airborne particulate matter

We developed and tested a methodology to extract both the size-segregated source apportionment of atmospheric aerosol and the size distribution of each detected element. The experiment is based on the parallel use of a standard low-volume sampler to collect Particulate Matter (PM) and an Optical Particle Counter (OPC). The approach is complementary to size-segregated PM sampling, and it was tested versus a 12-stage cascade impactor. Samples were collected inside the urban area of Genoa (Italy) and their elemental composition was measured by Energy Dispersive-X Ray Fluorescence (ED-XRF). Positive Matrix Factorization (PMF) was applied to time series of elemental concentrations to identify major PM sources, and both PM mass concentration and size-segregated particle number concentration were apportioned. Source profiles and temporal trends extracted by PMF were analyzed together with the OPC data to obtain the size distribution for several elements. The new methodology proved to be reliable for the PM apportionment as well as in providing the elemental concentrations in PM10, PM2.5, and PM1 (PM with aerodynamic diameter, D_ae < 10, 2.5, and 1 μm, respectively). The elemental size distributions are in good agreement with those obtained by the cascade impactor for several elements but some discrepancies, in particular for traffic emissions, are stressed and discussed in the text. The new methodology has two main advantages: it only requires standard semi-automatic sampling equipment and compositional analysis and it provides size-segregated information averaged over quite long periods (typically several months). This is particularly important since campaigns with cascade impactors are generally laborious and thus limited to short periods.     

New remains of the enigmatic cetartiodactyl Bugtitherium grandincisivum Pilgrim, 1908, from the upper Oligocene of the Bugti Hills (Balochistan, Pakistan)

Newly discovered fossil material of the enigmatic cetartiodactyl Bugtitherium grandincisivum from the upper Oligocene of the Bugti Member of the Chitarwata Formation in the Bugti Hills (Balochistan, Pakistan) is reported. These new specimens consist of two fragmentary muzzles (one preserving the first incisors and belonging to a juvenile) and a fragmentary right mandible with m3. The morphologies of the anterior dentition and m3 provided by these new specimens confirm the validity of the genus Bugtitherium and advocate probable anthracotheriid affinity for the genus rather than entelodontid or suoid affinities, but do not definitively close the debate about Bugtitherium’s familial affinities within Cetartiodactyla. Although still poorly documented, this large-sized anthracotheriid-like cetartiodactyl is a possible key form for understanding the early evolution of hippos, and, in turn, the ancestry of whales, because of both its morphological similarities with hippos and primitive Paleogene whales and its Tethysian distribution.     

A Kinetic Study of Aerobic Propane Uptake and Cometabolic Degradation of Chloroform, cis-Dichloroethylene and Trichloroetylene in Microcosms with Groundwater/Aquifer Solids

The focus of this study was to compare the behavior of different consortiums of aerobic propane-utilizing microorganisms, with respect to both the lag time for growth after exposure to propane, and their ability to transform three chlorinated aliphatic hydrocarbons (CAHs): chloroform (CF), cis-dichloroethylene (c-DCE) and trichloroethylene (TCE). Thirty-three slurry microcosms, representing seven combinations of aquifer solids and groundwater were constructed for this study. The lag time required for establishing propane-utilizing consortiums ranged between 24 and 29 days in 6 of the 7 combinations. Kinetic tests were performed with respect to propane utilization and CAH transformation. After CAH exposure, the ability of the microorganisms to metabolize propane was significantly reduced. CF and TCE were transformed more slowly than c-DCE, the average values of the initial transformation rates being equal to 0.10 ± 0.04, 0.09 ± 0.05 and 0.98 ± 0.18 mol/(L h),respectively. CF caused the greatest reduction in propane uptake rates, whereas c-DCE exhibited an apparently reversible negative effect on propane uptake rates. The estimates of the Monod half-saturation constants relative to CF, TCE and c-DCE resulted in the 2–3 mol/L range, but were characterized by a high degree of uncertainty.     

Sex attractant of an arctiid moth (Utetheisa ornatrix): A pulsed chemical signal

Summary The sex attractant pheromone produced by the female of the moth Utetheisa ornatrix was shown to contain Z, Z, Z-3, 6, 9-heneicosatriene. The compound, whose structure was confirmed by synthesis, proved active in electroantennogram and field bioassays. Pheromone emission occurs discontinuously, in the form of short pulses (pulse repetition rate=1.5±0.2 pulses/s). It is argued that such temporal patterning — which had not previously been demonstrated for an airborne chemical signal — can provide close-range orientation cues to the male moth as it seeks out the female.     

A combined analysis to identify airborne PM10 sources

A two step procedure that combines an air dispersion model with a receptor model was used to identify the key sources that contribute to air levels of suspended particulate matter. The contribution to PM(10) concentrations measured at four monitoring sites in San Nicolas, Argentina, of the following sources, a thermal power plant, an integrated steel mill, motor vehicle exhaust fumes, and finally dust from paved and unpaved roads, have been analysed. Moreover, an air dispersion model was used to estimate the contribution of the thermal power plant, emissions of which have been described in depth by means of hourly fuel consumption and specific emission factors. The ratio "apportionment coefficient" was introduced to relate the contribution of this source to the measured 24 h PM(10) concentrations by analysing the frequency of occurrence of connecting winds between the power plant and each monitoring site. In San Nicolas 70% of the PM(10) sampled at three of the four monitoring sites could be attributed to the power plant in those scenarios where winds connected the facility's tall point sources with the sampling locations. The contribution to the measured PM(10) levels of the rest of the sources that are present in the analysed area was confirmed by way of receptor models. For this purpose, the multielemental composition of 41 samples was determined by Wavelength Dispersive X-ray Fluorescence analysis. In order to ascertain the underlying correlations between PM(10) samples and potential sources, Principal Component Analysis was performed on the standard matrix of composition profiles, which comprises the measured PM(10) samples being enlarged with the composition profiles of the potential contributing sources. The diagonalization of the covariance matrix was used as a screening procedure to differentiate the most likely contributing sources from those that were not significant.