Flexural response of the Venetian foreland to the Southalpine tectonics along the TRANSALP profile

The Venetian Basin was affected by flexure related to the Southalpine shortening phase during the Middle Miocene – Early Pliocene. This downbending is quantified here using a two‐dimensional flexural model. A recently improved data set on basin geometry based on the bottom of the Serravallian–Tortonian clastic wedge, on palaeobathymetry and gravity anomalies is used to constrain the components of flexure and to test the importance of the initial bathymetry in evaluating the contribution of surface loads to deflection. A good fit is obtained assuming a northward broken plate configuration of the downbent Adriatic plate with an effective elastic thickness of 20 km. Results highlight that, in the studied region, flexure related to the Eastern Southern Alps is totally due to surface loads (topographic load partly replacing initial bathymetry) and that no hidden loads are required. Furthermore, the palaeobathymetry contributes up to 50% to the total flexure in the studied region.     

Glutathione-mediated chlorothalonil detoxification in channel catfish gills

Maintenance of the glutathione (GSH) pathway is critical in guarding against the toxic effects of a variety of pollutants. However, despite their importance as an initial line of defense against waterborne toxicants, little is known regarding the role of fish gills in GSH-mediated xenobiotic metabolism. In these studies, the role of channel catfish gills in the detoxification of 2,4,5,6-tetrachloroisophthalonitrile (chlorothalonil), an electrophilic fungicide, was examined. Chlorothalonil was metabolized in vitro by gill cytosolic and microsomal glutathione S-transferases (GSTs). Chlorothalonil metabolism by cytosolic fructions was reduced markedly when GSH was omitted from reaction mixtures. Microsomal metabolism of chlorothalonil did not occur in the absence of GSH and in the presence of an NADPH-regenerating system lacking GSH. Channel catfish exposed in vivo to chlorothalonil had increased gill GSH and cysteine concentrations after 72 h exposure, and increased gill gamma-glutamylcysteine synthetase (GCS) activity at 144 h of exposure. Our results show that the gills play an important role in the metabolism and detoxification of chlorothalonil in the channel catfish. Catfish can maintain elevated gill GSH concentrations in the presence of chlorothalonil by increasing gill cysteine concentrations.     

A First Generation Stochastic Bioeconomic Analysis of Algal Bloom Control in a Coastal Lagoon (Sacca di Goro, Po River Delta)

Abstract. In this work we have developed a very simple stochastic mathematical model of Ulva spp. growth to quantitatively evaluate the economic costs of algal harvesting and the related benefits in terms of avoided'economic loss'of clam production due to an effective prevention of algal blooms and the consequent anoxic crises. Algal growth was simulated by means of a discrete time difference equation of Ulva biomass where the finite growth rate depends only upon water temperature. In order to explicitly include environmental variability, a seasonal autoregressive model calibrated on available data was used to simulate water temperature. Different harvesting scenarios were analysed in terms of the number of harvesting vessels employed and the threshold biomass of Ulva at which vessels start to operate. Costs of algal harvesting and disposal, as well as monetary damages resulting from the collapse of clam production as a consequence of algal blooms, were assessed by interviewing the managers of the Clam Fishermen's Union of Goro. A Monte Carlo approach was used to estimate the mean and total statistical distribution of costs and benefits of different harvesting strategies. Our analysis shows that the most cost-effective management policy is attained with 4–6 vessels operating at low algal density able to harvest as much Ulva as possible with intensive and short interventions at the beginning of the seasonal growth.     

Ab-initio structure, energy and stable Cr isotopes equilibrium fractionation of some geochemically relevant H-O-Cr-Cl complexes

Twelve Cr(III) molecules and six Cr(VI) molecules of geochemical interest in the system Cr-H-O-Cl were investigated by ab initio Density Functional Theory in the aim of determining stationary state geometries, electronic energies and vibrational properties. The vibrational analysis conducted on the ⁵⁰Cr, ⁵²Cr, ⁵³Cr and ⁵⁴Cr isotopomers indicates important separative effects which result in mass spectrometric measurable fractionation factors in a wide thermal range. The effect of the central cation on the computed vibrational modes is interpreted in terms of Redlich’s product rule with the introduction of an isotopic ergodicity factor related to the effect of bulk molecular masses and momenta of inertia about the principal rotational axes. After the initial gas phase optimization, some relevant molecules were subjected to the effects of reaction field through Onsager’s Model, Tomasi’s continuum Model and Conductor-like Screening Model procedures. Structures and vibrational properties prove in all cases not to be severely affected by solvation, although the effect of the reaction field is to reduce somewhat the isotopic fractionation in Cr(III)-Cr(VI) aqueous redox equilibria, with respect to the gaseous state. Some of the computed separative effects are applicable to geochemical investigations.     

The Central Main Ethiopian Rift is younger than 8 Ma: confirmation through apatite fission‐track thermochronology

An isolated block of Precambrian basement rocks and Mesozoic sediments is exposed at Kella along the western margin of the Central Main Ethiopian Rift (MER), surrounded by Tertiary to Quaternary volcanic rocks. Apatite fission‐track thermochronology on two basement samples yielded ages of 7.2 ± 1.0 Ma and 6.7 ± 3.0 Ma and a long mean track length (>14.5 μm). Rapid Late Miocene cooling is attributed to denudation related to rifting. Despite the paucity of data, due to the absence of suitable lithologies in the area, our data confirm that the Central MER is younger than 8 Ma as recently proposed on the basis of field evidence and radiometric dating of volcanics. This implies that the Central MER formed after the Northern MER, indicating a diachronous development of this third arm of the Red Sea–Gulf of Aden–Ethiopian Rift system. Terra Nova, 00, 000–000, 2010     

A new late glacial to early Holocene palaeobotanical and archaeological record in the Eastern Pre‐Alps: the Palughetto basin (Cansiglio Plateau,Italy)

A late glacial to early Holocene lacustrine and peat succession, rich in conifer remains and including some palaeolithic flint artefacts, has been investigated in the Palughetto intermorainic basin (Venetian Pre‐Alps). The geomorphological and stratigraphical relationships, ¹⁴C dates and pollen analyses allow a reconstruction of the environmental history of the basin and provide significant insights into the reforestation and peopling of the Pre‐Alps. The onset of peat accumulation is dated to 14.4–14.1 kyr cal. BP, coinciding with reforestation at middle altitudes that immediately post‐dates the immigration of Larix decidua and Picea abies subsp. europaea. Plant macrofossils point to the expansion of spruce about 14.3 kyr cal. BP, so far one of the earliest directly dated in the late glacial period of southern Europe. The previous hypothesis of an early Holocene spruce immigration in the Southern Alps from Slovenia needs reconsideration. Organic sedimentation stopped at the end of the Younger Dryas and was followed by the evolution of hydromorphic soils containing lithic artefacts, anthropic structures and wood charcoal. The typological features of the flint implements refer human occupation of the site to the end of the recent Epigravettian. Charcoals yielded dates either consistent with, or younger than, the archaeological chronology, in the early and middle Holocene. Copyright © 2000 John Wiley & Sons, Ltd.     

The extended economic zone,the coastal state,and economic development

The recently created exclusive economic zones constitute windfall gains for some coastal states. However, windfall gains, such as the New World's gold for Spain and oil for OPEC, are notoriously difficult to transform into permanent wealth and income streams. These difficulties are discussed in this paper. In addition, a case study of the asset values of fisheries in areas of the NW and W Central Pacific Ocean is presented in detail. For nine countries, the changes in catch, both quantity and value, which resulted from establishment of the EEZ are used as estimators of the windfall gains.     

Solubility and speciation of sulfur in silicate melts: The Conjugated Toop-Samis-Flood-Grjotheim (CTSFG) model

A Conjugated Toop-Samis-Flood-Grjotheim (CTSFG) model is developed by combining the framework of the Toop-Samis polymeric approach with the Flood-Grjotheim theoretical treatment of silicate melts and slags. Electrically equivalent ion fractions are computed over the appropriate matrixes (anionic and cationic) in a Temkin notation for fused salts, and are used to weigh the contribution of the various disproportionation reactions of type: