1,721,013 research outputs found
Inquinamento salino ed antropico degli acquiferi costieri della murgia e del Salento: azioni di salvaguardia
No full textInquinamento di origine antropica ed inquinamento salino sono determinati da attività diverse e potenzialmente controllabili separatamente: tuttavia i fenomeni, nella gran parte degli acquiferi costieri ricadenti in aree densamente popolate, sono normalmente sovrapposti e la loro interconnessione rende necessaria, per comprendere il primo, la conoscenza dell’altro.
Negli ultimi decenni la situazione di tali acquiferi, particolarmente nell’area mediterranea, si è deteriorata profondamente, anche per effetto dell’ulteriore sovrapporsi degli effetti del cambio climatico. Come conseguenza di sovrasfruttamento, inquinamento e cambio climatico, i regimi naturali di flusso di tali acquiferi costieri risultano oggi profondamente disturbati, con mobilizzazione di acque prima isolate rispetto al deflusso attivo, con l’attivazione di cortocircuiti nel trasporto degli inquinanti e con una modifica della qualità del trasporto verso i mari.
Gli acquiferi costieri carsici della Murgia e del Salento soffrono dei problemi suddetti ed i risultati sono nettamente percepibili dalle popolazioni, almeno in termini di scarsità complessiva di risorse idriche e peggioramento globale del clima. Lo stato d’inquinamento delle falde rimane invece, nei suoi effetti, meno direttamente riconoscibile dagli utenti.
Occorre qui ricordare che le risorse idriche sotterranee dei suddetti acquiferi sono a tutt’oggi una risorsa molto importante anche ai fini del soddisfacimento della domanda idropotabile. Basti pensare che, in momenti di emergenza idrica, per incrementare la disponibilità idropotabile in Murgia vengono attivati prelievi da pozzi e che nel Salento sono prelevati per questi scopi, continuativamente, più di 4 m3/s. Tutto ciò senza pensare al crescente fabbisogno del comparto agricolo e zootecnico.
Le considerazioni che seguono in tema di inquinamento salino ed antropico delle risorse suddette sono basate su dati occasionalmente raccolti per scopo di ricerca scientifica che non possiedono carattere di sistematicità: l’assenza di controllo che è seguita ai dettami del Piano di Risanamento Idrico costituisce una lacuna gravissima, tale che ad oggi non si possiede un quadro affidabile di riferimento per impostare seriamente azioni di salvaguardia e recupero che non possono tuttavia essere più procrastinate
Hydrogeological implications of man-made agricultural transformations of the karstic soil textures of Alta Murgia (Puglia, Southern Italy).
No full textHuman induced hydrological changes and sinkholes in the gypsum karst of Lesina Marina area (Foggia Province, Italy)
No full textHydrological and hydrogeological hazard coming from man made agricultural transformations of the soils of the Murgia (Puglia, Southern Italy).
No full textReply to the discussion on ‘Coastal and inland karst morphologies driven by sea level stands: a GIS based method for their evaluation’ by Filomena Canora, Dolores Fidelibus and Giuseppe Spilotro (2012)
No full textThe authors welcome the discussion concerning their paper ‘Coastal and inland karst morphologies driven by sea level stands: a GIS based method for their evaluation’ by F. Canora, D. Fidelibus, G. Spilotro, made by J. De Waele and M. Parise. It provides an opportunity to open a debate about the significance
of geomorphological studies at different scales, both generally, and for the specific area of study (Murgia, Southern Italy)
Anisotropy of hydraulic conductivity through shallow geophysical surveys
No full textA geophysical investigation, including surface seismic refraction and electrical resistivity
methods with radial scanning, was carried out at two test sites of the Apulia region (Italy), in carbonate and
evaporite environments characterized by karstic processes. The main aim of the studies was to test the
effectiveness of the above mentioned methods to highlight the anisotropy of hydraulic conductivity of the
rock masses on the base of accurate surface and subsurface analysis of the karstic features and flow
conditions. The electrical resistivity method provided useful indications about the nature of the void filler
(water or residual soils) along the fracture and joint families; the seismic refraction method gave, in a
fractured and karstified system, information on the loss of material on the base of fractures knowledge of pwaves
velocity, density and Poisson ratio of the intact material and of the joint enlargements filler. The
radial scanning configurations revealed very useful in giving a well based forecast of karst development
directions; the combination of different geophysical techniques allowed reducing uncertainty linked to
interpretation of discrete values of physical properties in jointed rock masses and evidencing the anisotropy
features
Human induced hydrological changes and sinkholes in the gypsum karst of Lesina Marina area (Foggia Province, Italy).
No full textHydrological and hydrogeological hazards coming from man-made agricultural transformations of the soils of the Murgia (Puglia, Southern Italy).
No full textRilevanza idrogeologica delle tessiture epicarsiche e delle forme carsiche dell’Alta Murgia (Puglia).
No full textStudies on different kinds of salinisation in the groundwaters of the Ionian coastal plain of the Basilicata region.
No full textThe research by now carried out on the Ionian coastal plain of the Basilicata region allowed defining, for
the first time, that the coastal plain is constituted by a hydrogeological system formed by three kinds of
aquifers, well confined at the bottom by the blue clay basement. The tectonic evolution of the region
affected the clay basement during its sedimentation, followed by the erosion by five rivers and subsequent
deposition of alluvial sediments. As a consequence of faulting and fissuring, and following sea level
changes, the hydrogeological system and the basement have been subject in geological times to seawater
intrusion episodes. Mainly the construction of 17 dams and small barrages for water storage, together with
the diversion on the five main rivers or in their basins, but also the land reclamation during the 20th century
and practices, deeply modified the hydrology of the coastal plain by strongly reducing natural superficial
flow and by changing periods and areas of recharge. The geomorphologic features of the coastal border,
the recent sea level changes and the human activities, added to the above complexity, brought forth the
conditions in the hydrogeological system for the existence of a number of salinisation sources whose
effects somewhere overlap: salt water from superficial intrusion of seawater in the rear dune ponds or in
the river mouths, salt water from overexploited alluvial aquifers, salt diffusion from interstitial water of the
over-consolidated marine blue clays, solution of sulphates from evaporite deposits and salt concentration
due to recycling of irrigation water. Specific situations of salt concentration from human activities have
been also recognized in some sites. The high amount of water used for irrigation and, in the dry seasons,
the overexploitation of groundwaters, act, in the different environments, favouring or limiting the
salinisation. A detailed study, which was carried out on the base of stratigraphic data, temperature and
conductivity logs, and chemical analyses of groundwaters, contributed to discriminate the different
salinisation sources
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