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A geophysical and geochemical approach for seawater intrusion assessment in the Acquedolci coastal aquifer (Northern Sicily) 总被引:2,自引:0,他引:2
Vertical electrical sounding (VES’) surveys and chemical analyses of groundwater have been executed in the coastal plain of
Acquedolci (Northern Sicily), with the aim to circumscribe seawater intrusion phenomena. This urbanized area is representative
of a more general problem interesting most of Mediterranean littoral areas, where intensive overdraft favors a heavy seawater
intrusion through the coastline. Aquifer resistivity seems decisively to be conditioned by the chlorine and magnesium content
in the main aquifer of the region. Schlumberger VES’, together with piezometric and chemical–physical information of groundwater,
allowed us to perform hydrogeological and geophysical elaborations, to propose the occurrence of a relatively narrow belt
marked by fresh–salt water mixing. In the considered plain, pollution risk studies have been already realized by authors with
the proposal to identify—by parametric and synthetic zoning of significant hydrogeological elements—the most vulnerable sectors.
In detail, an intrinsic vulnerability mapping has been already performed, applying the well-known SINTACS system. This paper
intends to give—in this sector of Sicily—an example of integration of different methodologies, showing the role of geophysics
to describe the degradation of aquifers on the whole as well as to assess their pollution risk better. 相似文献
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Alessandra Gallo Francesco Silvestre Annunziata Cuomo Fabrizia Papoff Elisabetta Tosti 《Marine Ecology》2011,32(2):222-231
Environmental pollution due to anthropogenic activities may exert an adverse impact on the reproductive mechanisms of animals. In particular, environmental chemicals introduced into seawater are able to disrupt the normal development and function of the reproductive system of marine animals. In this study, we have used the whole‐cell voltage clamp technique to examine the effects of four metals – lead, cadmium, mercury, and zinc – on reproductive mechanisms of the marine ascidian Ciona intestinalis (tunicates). In particular, we measured the effect of metals on plasma membrane electrical properties, the steady‐state conductance, the fertilization current in the mature oocyte, and larval development. Results show that oocyte voltage‐gated sodium currents are significantly reduced by all four metals, steady‐state conductance is affected only by zinc, and post‐fertilization contraction is inhibited only by lead. The fertilization current is suppressed in the presence of zinc and mercury. Embryo development up to larval stage is inhibited by zinc and mercury exposure with a reversible effect; however, a long‐term effect on larval morphology was observed. After exposure to cadmium, fertilization occurs but gives rise to abnormal larval development. These findings highlight the point that exposure to metals represents a significant risk factor for the physiology of reproduction of marine species and suggest a possible role of the C. intestinalis as a bioindicator for marine pollution monitoring. 相似文献
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