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HUMAN INDUCED HYDROGEOLOGICAL CHANGES AND SINKHOLES IN THE COASTAL GYPSUM KARST OF LESINA MARINA AREA (FOGGIA PROVINCE, ITALY)
No full textIn 1930, a canal was excavated to connect the Lesina Lagoon with the Adriatic Sea, modifying the track of the
previous existing Acquarotta canal. The 1100 m long stretch of the canal situated next to the coast exposed
unknown highly cavernous gypsum bedrock underlying a loose sandy cover. During the last two decades, a
large number of cover collapse and cover suffosion sinkholes have formed along two bands situated next to
the canal, impinging the adjacent Lesina Marina residential area. The area affected by subsidence has
increased exponentially from 1999 to 2009. The tight spatial correlation between the sinkholes and the canal
reveals that the subsidence phenomenon has been induced by the local hydrogeological changes caused by
the canal in the coastal evaporite aquifer: (1) Local lowering of the average water table. (2) Deflection of the
groundwater flow lines towards the canal and increase in flow velocity. (3) Amplification of the groundwater
level oscillations, largely controlled by the tidal regime. (4) Local reversals in the groundwater flow, changing
the canal temporarily from effluent to influent. These changes in the hydrogeological functioning of the
system have favoured both internal erosion and karstification processes. Hydrochemical evidence reveals that
gypsum dissolution is a currently active process favoured by fresh water and sea water mixing and cationexchange
processes. Most likely, the partial replacement of a concrete lining in the canal by pervious gabions
in 1993 provided more adequate conditions for the evacuation of the sediments filling the karst conduits,
accelerating internal erosion and sinkhole development
Application of short time series analysis for the hydrodynamic characterization of a coastal karst aquifer: the Salento aquifer (Southern Italy)
No full textDaily precipitation and groundwater level data, registered at 7 rain gauge stations and 11 monitoring wells in the Salento coastal karst aquifer (Southern Italy) were subject to short time series analyses to evaluate the hydrodynamic response of the aquifer. Results show that the Salento karst system has in general great storage capacity, which suggests a poor degree of aquifer karstification, and dominance in the permeability structure of not well-developed hierarchical karst networks. Baseflow generally dominates on quick flow, which only occasionally occurs. The dominant hydraulic behaviour is unimodal baseflow with a bimodal baseflow and quick flow one from time to time. Some local specific features, which emerge depending on the rainfall frequency and depth, and the geological and structural characteristics, point out that some components of the permeability structure, as the epikarst and major faults, only activate depending on the characteristics of the input. The study is novel because the analyses concerned specific sets of hydrological years from 2007 to 2011; also, because the analysis was conducted for a coastal karst aquifer of significant size, characterized by a regional groundwater flow system with an unsteady lower boundary, without inland freshwater springs, and significant exploitation by wells
Cascading vulnerability scenarios in the management of groundwater depletion and salinization in semi-arid areas
Get PDFMeteorological droughts can have unexpected cascading consequences on social, economic, and environmental systems, which depend on the starting conditions of affected systems, and on natural and human drivers. In coastal areas, droughts propagate their effects to coastal aquifers, causing exacerbation of withdrawals with consequent worsening of groundwater quality and quantity. Considering the area of Lecce province (Salento
peninsula, Apulia region, Southern Italy), the study outlines the non-linear cascading paths related to groundwater depletion and salinization in an urbanized coastal region depending quite entirely on groundwater resources of a coastal karst aquifer. The outline of cascading events is the outcome of a scenario building process carried out through semi-structured interviews to water management stakeholders. The cascading scenarios relate to different degrees of system resilience and describe chain effects and vulnerabilities. These scenarios can have significant outcomes in improving water management practices and increasing both local manager and end-user awareness about potential and unexpected cascading consequences related to droughts
Lithological and Geotechnical Features of the Calcarenites in the West of the Murgian Platform
No full textIdrogeologia della regione del Monte Vulture
No full textL'edificio vulcanico del Monte Vulture è sede di
una vasta circolazione. idrica sotterranea, che si manifesta
dalle quote più elevate secondo linee di flusso a sviluppo approssimativamente
radiale. Essa è condizionata dalle strutture
create dalle sequenze laviche e piro clastiche del vulcano,
dai loro successivi assestamenti e deformazioni tettoniche e
pseudo tettoniche, fattori che hanno determinato permeabilità
ed anisotropia del drenaggio sotterraneo.
I punti principali di emergenza della falda idrica si rinvengono
in corrispondenza dei Laghi di Monticchio e al contatto
dei terreni vulcanici con il substrato sedimentario, alle
estremità della faglia di Valle dei Grigi-Fosso del Corbo.
La vulnerabilità intrinseca dell'acquifero è stata elaborata
sulla base dei piani informativi elementari relativi ai caratteri
idrogeologici e climatici del territorio. Indagini più recenti
hanno permesso di tracciare la mappa della concentrazione
di Nitrati nelle acque sotterranee. Il confronto tra i dati
invernali-estivi e con la carta della vulnerabilità evidenzia il
ruolo determinante della circolazione idrica sotterranea nella
diluizione stagionale e totale dell'inquinante.The M. Vulture volcanic edifice represents a huge aquifer: groundwater circulates from the highest altitudes according to radial streamlines. Groundwater circulation is conditioned from the structures created from the effusive and pyroclastic sequences of the volcano, from their successive arrangements and tectonic and pseudo-tectonic deformations: such factors govern the permeability and anisotropy features of the aquifer: The main points of groundwater emergence locate in correspondence of the Monticchio Lakes and at the contact of volcanic rocks with the sedimentary basement, to the extremities of the Valle dei Grigi-Fosso del Corbo fault. The intrinsic vulnerability of the aquifer has been elaborated on the base of the necessary informative plans related to the hydrogeological and climatic features of the territory. More recent surveys allowed reconstructing the map of the nitrate concentrations in groundwater: The comparison between the winter-summer data and the vulnerability map evidences the determining role of the water groundwater circulation in the seasonal and total dilution of the pollutants
L’acqua, le tecniche di captazione e gli insediamenti umani sul bordo occidentale dell’altopiano murgiano (Sud Italia)
No full textLungo la fascia di bordo tra l’altopiano
della Murgia ad Est e la fossa Bradanica ad
Ovest, confine tra le regioni Puglia e Basilicata,
l’evoluzione millenaria degli insediamenti
umani e della civilizzazione risulta condizionata
dalla disponibilità della risorsa idrica e
procede di pari passo con l’evoluzione della
cultura dell’acqua. Le tecniche sviluppate
evidenziano una peculiare conoscenza del
territorio associata ad una attenta cultura
dell’acqua, non solo in termini tecnologici
ma anche di gestione della risorsa. Il percorso
evolutivo non è stato strettamente sequenziale
e sincrono nei diversi punti del territorio; in
ogni caso ci restituisce oggi opere, in molti
casi ancora funzionanti ed in altri casi da riabilitare,
nel segno di una cultura dell’acqua
non superata e da tramandare
Convective Thermal Field Reconstruction by Ordinary Kriging in Karstic Aquifers (Puglia, Italy): Geostatistical Analysis of Anisotropy
No full textThe flow system in fractured aquifers is complex to define. A reliable outline of flow system in such a type of aquifers can be obtained by using natural tracers: among them, temperature demonstrates very effective. Convective thermal fields, resulting from convective disturb on conductive thermal field, can be rea-sonably interpreted like analogues of flow systems. A geostatistical approach by Ordinary Kriging has been applied to groundwater temperature data obtained from temperature logs performed in two fractured karstic and coastal aquifers (Murge and Salento) of Southern Italy. The variographic analysis shows the potential of the geostatistical approach in outlining regional and local scale anisotropies. Moreover, vertical and horizontal Ordinary Kriging temperature estimations at different depths allow recognizing main recharge areas and preferential flow-pathways
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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