The abandoned antimony-mines of SE Sardinia: impact on surface waters

This study investigates the impact of abandoned Sb-mines on the Flumendosa River, which is the most important water resource in southern Sardinia. Hydrogeochemical surveys carried out in 2005 and 2006 indicated a significant impact of waters flowing out from adits, slag, tailings and waste materials on surface waters. The contaminated waters show alkaline pH, and high dissolved SO4, Sb and As (up to 1900, 9.6 and 3.5 mg/L, respectively). Although the flow rates of drainages from the mining area are usually low (in the range of < 0.1 to 1 L/s), the contribution to dissolved concentrations of Sb in the streams downstream of mines is high. Sampling under high flow conditions in the Flumendosa River before the confluence with the contaminated streams showed Sb concentrations below the limits established by the guidelines of World Health Organization for drinking water (i.e. 20 g/L), while downstream of the confluence dissolved Sb was 32 g/L. Contamination in the Flumendosa extended 16 km, and attenuation (15 g/L Sb) was only observed close to the Flumendosa mouth

Risorse idriche e rischio di contaminazione

2006-11-28Sardegna Ricerche, Edificio 2, Località Piscinamanna 09010 Pula (CA) - ItaliaKick-off Meeting del Progetto GRIDA

AQUAGRID: an extensible platform for collaborative problem solving in groundwater protection

AQUAGRID is the subsurface hydrology computational service of the Sardinian GRIDA3 infrastructure, designed to deliver complex environmental applications via a user-friendly Web portal. The service aims to provide to water professionals integrated modeling tools to solve water resources management problems and aid decision making for contaminated soil and groundwater. In this paper, the AQUAGRID application concept and enabling technologies are illustrated. At the heart of the service are the computational models to simulate complex and large groundwater flow and contaminant transport problems and geochemical speciation. AQUAGRID is built on top of compute-Grid technologies by means of the EnginFrame Grid framework. Distributed data management is provided by the Storage Resource Broker data-Grid middleware. The resulting environment allows end-users to perform groundwater simulations and to visualize and interact with their results, using graphs, 3D images and annotated maps. The problem solving capability of the platform is demonstrated using the results of two case studies deployed

L’analyse de la structure de communauté à l’aide de modèles nuls révèle que la qualité de la parcelle influence la conservation de peuplements aviens complexes dans les habitats méditerranéens

The bird communities of the Presidential Estate of Castelporziano (Rome, Italy) were studied to determine their structure in a set of different natural habitats. This study area presents a complex ecosystem, formed by a mosaic of different habitats and their ecotones, having a high biodiversity level. Wetlands housed the highest number of bird species followed by oak forests. Bird communities of Castelporziano are characterized by high degrees of richness and complexity. Null model analyses revealed that the bird community was not randomly organized by Randomization Algorithm 2 (thus denoting that the generalist-specialist nature of the species reduced ecological similarity) nor by Randomization Algorithm 3 and Randomization Algorithm 4 (thus denoting that the types of resources utilized did not reduce ecological similarity). Based on this study, we will not only focus on conservation levels of single habitats for Mediterranean birds, but also modify the classical approach of ‘fragmentation biology’ with a new approach where the natural quality of all patches is evaluated with appropriate statistical toolsLes peuplements aviens de l'État Présidentiel de Castelporziano (Rome, Italie) ont été étudiés afin de déterminer leur structure dans une série de divers habitats naturels. La zone d'étude se présente comme un écosystème complexe, formé par une mosaïque d'habitats différents et de leurs écotones, possédant un haut niveau de biodiversité. Les zones humides hébergent le plus grand nombre d'espèces d'oiseaux, suivies par les forêts de chênes. Les peuplements aviens de Castelporziano sont caractérisés par de hauts degrés de richesse et de complexité. Les analyses par modèles nuls ont montré que la communauté avienne n'est pas organisée au hasard et ceci tant par l'algorithme de randomisation 2 (dénotant ainsi la nature généraliste-spécialiste de la similarité écologique réduite des espèces) que par les algorithmes de randomisation 3 et 4 (dénotant ainsi que les types de ressources utilisées ne réduisent pas la similarité écologique). Sur la base de cette étude nous insistons non seulement sur les niveaux de conservation des habitats isolés pour les oiseaux méditerranéens mais nous modifions également l'approche classique de la "biologie de la fragmentation" en une nouvelle approche où la qualité naturelle des parcelles est évaluée à l'aide d'outils statistiques appropriés

Impatto ambientale dell'attività mineraria in Sardegna: studi mineralogici e geochimici

Sardinia is characterized by a large variety of geologic and hydrologic environments, and by a rich wealth of mineral resources, that fueled a millennial history of mining activity. Therefore, it provides an excellent ground for studies of the environmental impact of mining activity. In this communication, we summarize the results of our studies, specifically concerning the deposits of Baccu Locci (polymetallic�Pb,As), Furtei (epithermal Au), Monteponi (Pb-Zn-Ag), and Montevecchio (Pb-Zn-Ag). In abandoned mining districts (Baccu Locci, Monteponi, and Montevecchio), because of a poor management of environmental issues, we observe significant heavy metal contamination. On the other hand, in the active Furtei mine the first four years of exploitation did not cause remarkable changes with respect to pre-mining baseline conditions