Modelling the Density Contrast Effect on a Chlorinated Hydrocarbon Plume Reaching the Shore Line

Diffused petroleum and chlorinated hydrocarbon contamination was detected in a sandy aquifer below a chemical plant in Southern Italy. The contamination was due to underground leaking tanks and pipes. The site is located near the shore line and is bordered by canals which, in combination with pumping wells, control the groundwater flow direction toward the sea. In this study, a comprehensive three-dimensional flow model was developed and calibrated to simulate the general groundwater flow system and to individuate a flow line. On this latter, a detailed field investigation was performed in order to determine the fate of dissolved hydrocarbons. Depth profiles obtained from multi-level samplers located along the modelled flow line, including measurements of hydrocarbons, all major ions and dissolved gasses, were used to constrain the conceptual model. These data were then included into a two-dimensional transport model in order to verify the efficacy of the hydraulic barrier (HB) in preventing the hydrocarbon plume to reach the shore line. Two different approaches were used in the transport simulation, one accounting for density-dependent flow and the other not. The calibrated models show that the plume length and consequently, the submarine groundwater discharge of contaminants is slightly different for the two approaches. For the simulation not accounting for the density contrast between freshwater and saltwater, the mass of contaminant discharged downstream to the HB was underestimated and also the reconstructed plume geometry was different than the observed. Moreover, the reconstruction of the saltwater intrusion interface (SWII) with the two different approaches was substantially different. This study demonstrates that at field site, variable density processes should be carefully taken into account not only when the modelling is devoted to the reconstruction of the SWII but also when the modelling is targeting the fate of hydrocarbons at sites affected by SWII, in order to provide accurate data on which soundly environmental management of the coastal zone can be based.     

Phylogeography and conservation perspectives of an endangered macaronesian endemic: Picconia azorica (Tutin) Knobl. (Oleaceae)

The Azores provide an excellent field test for research activities aimed at developing conservation strategies for endangered tree species. In this work, the urgency to promote Picconia azorica conservation programs addressed (a) insights into the biotaxonomy of the species (including an evaluation of its origin and relationships with the only congeneric species of P. azorica: P. excelsa from the Canary and Madeira islands) and (b) the evaluation of P. azorica genetic diversity. Plastid DNA sequence analysis and molecular markers (RFLP and SSR) were used for this purpose. Phylogenetic data suggest the monophyly of Picconia and support a late Miocene divergence of the two species. Three polymorphic cpSSR loci allowed the identification of five different haplotypes in P. azorica. Uniqueness and relictuality of lineages are presented and discussed. Picconia azorica intra-specific diversity patterns revealed low genetic diversity and a weak genetic structure, which could result from long-lasting ecological stability and efficient inter-island seed movement that have been severely affected in recent times. The species survival is at risk, and we suggest management practices focusing on ex situ and in situ conservation units based on eco-genetic data. Additional measures contributing to mild erosion of the genepool and to remove barriers to seed dispersal are indicated.     

A note on the insecticide sensitivity status of Meligethes species (Coleoptera: Nitidulidae) in Luxembourg

Journal of Plant Diseases and Protection - Adult pollen beetles, Meligethes spp. (Coleoptera: Nitidulidae), were sampled from 27 and 35 oilseed rape (Brassica napus subsp. oleifera) fields...     

Ovariohysterectomy in a dog by a hybrid NOTES technique

This report demonstrates the feasibility of an elective ovariosalpingohysterectomy by natural transluminal endoscopic surgery (NOTES) hybrid technique in a dog. A 5-mm abdominal cannula was used in combination with a 10-mm cannula (vaginal access). The patient's quick recovery and the absence of complications are indicative of the effectiveness of this surgery.     

Gastric and enteric phytobezoars caused by ingestion of persimmon in equids

CASE DESCRIPTION-13 equids (10 horses, 2 donkeys, and 1 pony) were examined for signs of colic (n = 7), weight loss (6), anorexia (3), and diarrhea (2). Ten equids were evaluated in the fall (September to November). Seven equids had a history of persimmon ingestion. CLINICAL FINDINGS-A diagnosis of phytobezoar caused by persimmon ingestion was made for all equids. Eight equids had gastric persimmon phytobezoars; 5 had enteric persimmon phytobezoars. Gastroscopy or gastroduodenoscopy revealed evidence of persimmon ingestion in 8 of 10 equids in which these procedures were performed. TREATMENT AND OUTCOME-2 of 13 equids were euthanatized prior to treatment. Supportive care was instituted in 11 of 13 equids, including IV administration of fluids (n = 8) and treatment with antimicrobials (5), NSAIDs (5), and gastric acid suppressants (4). Persimmon phytobezoar-specific treatments included dietary modification to a pelleted feed (n = 8); oral or nasogastric administration of cola or diet cola (4), cellulase (2), or mineral oil (2); surgery (4); and intrapersimmon phytobezoar injections with acetylcysteine (1). Medical treatment in 5 of 7 equids resulted in resolution of gastric persimmon phytobezoars. Seven of 8 equids with gastric persimmon phytobezoars and 1 of 5 equids with enteric persimmon phytobezoars survived > 1 year after hospital discharge. CLINICAL RELEVANCE-Historical knowledge of persimmon ingestion in equids with gastrointestinal disease warrants gastroduodenoscopy for evaluation of the presence of persimmon phytobezoars. In equids with gastric persimmon phytobezoars, medical management (including administration of cola or diet cola and dietary modification to a pelleted feed) may allow for persimmon phytobezoar dissolution.     

7000 years of Emiliania huxleyi viruses in the Black Sea

A 7000-year record of Coccolithovirus and its host, the calcifying haptophyte Emiliania huxleyi, was reconstructed on the basis of genetic signatures preserved in sediments underlying the Black Sea. The data show that the same virus and host populations can persist for centuries. Major changes in virus and host populations occurred during early sapropel deposition, ~5600 years ago, and throughout the formation of the coccolith-bearing sediments of Unit I during the past 2500 years, when the Black Sea experienced dramatic changes in hydrologic and nutrient regimes. Unit I saw a reoccurrence of the same host genotype thousands of years later in the presence of a different subset of viruses. Historical plankton virus populations can thus be included in paleoecological and paleoenvironmental studies.     

Woody species composition of chestnut stands in the Northern Apennines: the result of 200 years of changes in land use

Chestnut stands (orchards and coppices) are among the most typical elements of the southern European mountain landscape and a protected habitat (9260 Castanea sativa woods) according to the European Union (Directive 92/43/EEC). As an anthropogenic landscape, they require specific measures to address preservation or to guide their evolutionary trend. In the Northern Apennines, a landscape multiscalar-multitemporal approach was adopted to highlight factors that have acted on the evolution of this habitat and which still might affect either its preservation or its evolutionary dynamics. Using a diachronic GIS-approach, we analyzed old cadastral maps (drawn up 200 years ago), and aerial photographs. Both the present distribution pattern of the woody species and the incidence of important chestnut diseases were also surveyed. The factors explaining the current extent and species composition of the local chestnut forests confirm their status as an anthropogenic habitat. The present landscape distribution of chestnut woods is heavily linked to past human settlements. Chestnut blight and ink disease are more an indirect reason for past felling activities than an actual direct cause of damage to trees, because of the hypovirulence spread and the limited incidence of the ink disease. Vegetation dynamics of abandoned chestnut forests evolved only partly towards deciduous Beech and Hop Hornbeam stands, thus suggesting both the possibility of a recovery of this cultivation and the need for new criteria for its management.