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Aspetti dell'ecologia della lepre sarda (Lepus capensis mediterraneus) in aree della Sardegna meridionale. Some aspects of cape hare Lepus capensis mediterraneus ecology in Southern Sardinia
Get PDFNonostante la Lepre sarda (Lepus capensis mediterraneus) sia una specie soggetta a prelievo, poco o nulla si conosce circa la sua ecologia, ed in particolare in Provincia di Cagliari nessuna ricerca era stata fino ad ora condotta. Scopo di questa indagine è stato quello di individuare i valori di densità, dinamica di popolazione e selezione
dell'habitat. Sono stati effettuati dei conteggi notturni con l'uso di proiettori alogeni su percorsi campione negli anni 1994-95, 1995-96 e 1997-98; negli stessi anni sono stati inoltre acquisiti i dati relativi agli abbattimenti di Lepre nelle Autogestite della provincia.
Al fine di determinare la struttura delle popolazioni, per due anni è stato verificato il grado di ossificazione della cartilagine ulnare delle zampe nelle lepri abbattute.
La selezione dell'habitat nelle ore notturne è stata studiata confrontando l'uso con la disponibilità di habitat mediante il metodo degli intervalli fiduciali di Bonferroni. I risultati ottenuti mostrano valori di densità complessivamente bassi sia nelle aree aperte alla caccia che nelle zone protette (Oasi e Zone di Ripopolamento e Cattura). Le densità sono risultate più¹ elevate nelle zone a seminativi alternati a vaste superfici di macchia mediterranea
Ailanthus altissima (Miller) Swingle as a cause of immunoallergic respiratory manifestations
Get PDFIn questo lavoro gli autori mettono in correlazione le concentrazioni aeropolliniche di Ailanthus altissima(Miller) Swingle (Simaroubaceae) rilevate nell’atmosfera
della città di Cagliari (Sardegna meridionale, Italia) e del suo hinterland, con le sindromi allergiche causate, in alcuni pazienti atopici, dai pollini di questa pianta. Dalle indagini aerobiologiche è stato possibile mettere in evidenza come le più alte concentrazioni aeropolliniche di ailanto sono state riscontrate nel periodo tra aprile e giugno. Su un campione significativo di 74 pazienti, di sesso ed età diversa, ben 21 soggetti sono risultati positivi ai test allergologici
Studio idrogeologico degli acquiferi profondi del Sinis(Sardegna Centro-Occidentale)
Get PDFSinis area is located in the north western sector of Campidano plain, to the North of the Gulf of Oristano. In that sector of Sardinia underground waters constitute
the most important water resource for agriculture. In Sinis area two deep aquifers have been placed. The first, placed in the western part, is constituted by sands and gravels
and it is overhung by a very thick clayey marl’s layer. The water yeld of the confined aquifer has been determined by pumping tests from which it results that the pumping rate varies between 6 and 13.5 l/sec. The average Transmissivity is 1.7 x 10-3 m2/s. The other aquifer system, already known and studied for a long time, belongs to the alluvial
multilayered aquifer of Campidano. It is constituted by very permeable layers of sands and gravels alternated to impervious or semi confining silty clay layers. The Transmissivity of this aquifer results superior to 10-3 m2/sec. Pumping rates are at least 6-7 l/sec. Chemical analysis showed that some samples of water taken in the southern part of Sinis present some anomalous values and they show thermal waters typical characters. This fact is confirmed by the average temperatures around 23°C. It could be a ground water recharge by deep thermal waters, with which waters coming from Montiferru would be mixed
Saperi tradizionali e sviluppo locale: il comparto della produzione del miele in Sardegna
Get PDFA causa di particolari condizioni ambientali il miele sardo rappresenta un bene verticalmente differenziato con buone potenzialità di mercato. Il settore ha attraversato inoltre una fase di trasformazione tecnologica che ha portato al quasi totale abbandono del vecchio know how locale e alla sua sostituzione con le tecniche più moderne della gestione razionale dell’arnia. Ciononostante la produzione trova sbocco quasi esclusivamente sul mercato locale e il tessuto produttivo continua ad essere costituito da microimprese con scarsa o nulla tendenza a crescere. Il lavoro esamina, con un’indagine sul campo realizzata mediante un questionario, le principali caratteristiche del settore e le peculiarità che lo differenziano dagli altri settori tradizionali cercando di fornire una spiegazione del circolo vizioso generato dalla simultanea presenza di barriere all’entrata tecnologiche e di un tessuto produttivo molto frammentato che ha impedito lo sviluppo del settore
Nuova classificazione biostratigrafica e geocronologica delle unità formazionali oligoceniche e neogeniche della Sardegna. Correlazioni con le omologhe unità della Corsica
Get PDFRecent revisions in classification and the new definitions in the literature of late Paleogenic and Neogenic formations outcropping in the northern, central and
southern Sardinia provided by the authors have led to the preparation of a complete biostratigraphic and geochronological picture of the entire Sardinian Tertiary sedimentay basin. The lithostratigraphic units, of which the measured stratigraphic sections of reference will be given in another work, were placed in the most recent and up-to-date zonal classifications of Mediterranean planktonic Foraminifers associations and calcareous plankton. In this proposal for the reclassification of the stratigraphic successions of Sardinia’s Oligocene-Neogene, three main marine sedimentation cycles are recognized. These are silicoclastics and mixed silicoclastic-carbonatic sediments, sometimes richly fossiliferous, in which are inserted volcanic products going from acid to intermediate-basic and having a calcalkaline composition (the «Oligo-Miocene volcanic cycle») almost exclusively in the Aquitanian-Late Burdigalian interval. On the basis of a comparative analysis of autochthonous benthic associations, especially those with molluscs and of the textural characteristics of the sediments, the prevalent depositional environment is that of a platform and secondly of a slope, but in some cases fluvio-lacustrine and deltaic (preliminary data on the paleo-ecological aspects are
being prepared for publication). Of the three main sedimentation cycles, the first evolved between the Chattian-Aquitanian limit and the Late Burdigalian (N6 Zone); the second cycle began in the Uppermost Burdigalian, in correspondence to the upper part of the Globigerinoides trilobus Zone (N7 Zone) and closes in the Late Serravallian (G. siakensis Zone, G. siakensis - G. obliqua obliqua Subzone); finally, the third cycle begins in the Uppermost Serravallian and finishes in the Early Messinian, in correspondence to the upper part of biostratigraphic N17a Zone. The successions examined are also considered with reference to the major tectonic and volcanic events
which took place in Sardinia from the Oligocene to the Pliocene within the wider context of the geodynamic evolution of the western Mediterranean area. In particular, the first two sedimentary cycles which evolved from the end of the Oligocene and the Early-Middle Miocene would appear to be closely connected with the collision and postcollision
phases respectively of the northern Apennines. The northern Apennines collision phase appears to have manifested itself in Sardinia with an important transcurrent tectonic with transpressive and transtensive structures and with the
development of subsidence basins of the pull-apart type in correspondence to which the first Miocene sedimentary cycle and the associated calcalkaline volcanism developed.
The creation in the Burdigalian of the wide N-S Sardinian rift, in which the second Miocene sedimentary cycle evolved, is to be attributed to the subsequent phase of postcollision distension. The third Miocene sedimentary cycle becomes manifest, following a regressive phase, limited to the most subsident areas of the Logudoro -Sassari, Capo Frasca - Sinis and Cagliari regions. The marine ingression of the Early Pliocene, located in central Sardinia (Cava Fuile and Nuraghe Baboe Cabitza B nn. Formations) and in the south of the island (in drilling) is to be placed in connection with the strong resumption of the southern Tyrrhenian distensive tectonics towards the end of the Messinian and Pliocene, as well as with widespread alkaline, prevalently basaltic, volcanic activity (the «Plio-Pleistocene volcanic cycle»). In the Late-Middle Pliocene, between the Gulf of Cagliari and the Gulf of Oristano, there was the development of the
Campidano graben, filled with more than 500 m of continental deposits (the Samassi Formation). The four Corsican basins (Bonifacio, Saint Florent, Francardo, the
eastern Plain), in which Miocene and/or Pliocene sediments outcrop, show, starting from the summital Burdigalian, an evolution that is fairly parallel to what has been
recognized in the north of Sardinia. The formations of Aghione, Saint Florent, Cala di Labra and Bonifacio are in fact partly referable to the second Sardinian sedimentary
cycle. The subsequent phases characterized in Corsica by emersion, marine sedimentation (the Vadina and Urbino units), fluvio-deltaic sedimentation (the Aleria Formation) and further marine sedimentation (the Urbino, Casabianda, Propiano and Aiaccio units), are in Sardinia respectively correlated with the hiatus and/or erosion or continental
sedimentation in the Late Serravillian, with the Tortonian part of the third marine sedimentation cycle (the Monte San Michele Formation), with the Messinian part of the same cycle (the Capo San Marco, Sinis and Torre del Sevo Formations) and with the Nuraghe Baboe Cabitza B (Capo San Marco) Pliocene formation
The performance of Setar Models: a regime conditional evaluation of point, interval and density forecasts
Get PDFThe aim of this paper is to analyse the out-of-sample performance of SETAR models relative to a linear AR and a GARCH model using daily data for the Euro effective exchange rate. The evaluation is conducted on point, interval and density forecasts, unconditionally, over the whole forecast period, and conditional on specific regimes. The results show that overall the GARCH model is better able to capture the distributional features of the series and to predict higher-order moments than the SETAR models. However, from the results there is also a clear indication that the performance of the SETAR models improves significantly conditional on being on specific regimes
Studio idrogeologico del bacino del rio di Santa Caterina di Pittinuri(Cuglieri, Sardegna Centro-Occidentale)
Get PDFThe catchment area of the river Santa Caterina is located in western part of Montiferru, one of most important volcanic complex of Sardinia. In order to determine
the water balance of the basin, the base flow rates of streams and springs were measured for the purpose of assessing groundwater reservoirs and dynamic storage by means of depletion law of hydrogeologic system. Because of the prevalence of volcanics rocks a study of lava flow and fracture systems was required to determine the main directions of growndwater flow. It was found that hydrogeologic and hydrographic watershed do not coincide. In fact a fair amount of water out flow through bedding planes various lava flows
An equivalence criterion for PL-manifolds
Get PDFAim of the paper is to translate the homeomorphism problem for n-dimensional PL-manifolds, with or without boundary, into an equivalence problem for pseudosimplicial triangulations (i.e. a suitable generalization of simplicial triangulations, where two (curvilinear) simplices may intersect in more than one face), by means of a finite number of moves, called (geometric) dipole moves. Note that the environment of the present work is closely related to the representation method for PL-manifolds via
edge-colorured graphs, since (n+1)-coloured graphs representing n-manifolds are a «discrete way» to visualize suitable pseudosimplicial triangulations. From the graphtheoretical point of view, the equivalence problem was already faced – and solved – in [FG] for closed n-manifolds and in [C2] in the general 3-dimensional setting; here, the
equivalence criterion via (geometric) dipole moves is proved to hold for the whole class of PL n-manifolds; moreover, it is proved to be equivariant with respect to boundary triangulation
Malacofaune spiaggiate della costa occidentale della Sardegna. Fisiografia e batimetria dei fondali marini di provenienza
Get PDFHerein are presented the results of research of an autoecological nature concerning beached malacological fauna gathered along the west coast of Sardinia.
The resulting data contribute to defining the composition and structure of thanatocoenosis gathered at 35 biosites and allow estimation of the «bathymetric maximum» (30-40
metres) equivalent to the greatest depth at which sediments and the remains of molluscs within them are mobilized. Homogeneous «timed» sampling led to useful statistical
comparisons between the different malacological associations gathered and made it possible to recognize the stocks of benthic populations most involved in the transportation of material: AP, SFBC, HP. By means of the autoecological analysis of recognized species, especially using data on texture, way of life and biocoenotic significance, the paper discusses the physiography of the sea bottoms mobilized in front of the biosites sampled. A database on the systematic taxonomy and autoecology of the 223 species identified, which represents a point of reference also in palaeoecological research into Neogenic and Quaternary fossiliferous deposits of Sardinia, is presented
La salute e la famiglia innanzitutto. I valori di riferimento dei giovani attraverso un'indagine empirica
Get PDFStarting from evidence advanced in previous research, the Authors,
carry out an analysis on a sample of school pupils. They were asked to indicate
what things in their opinion are more or less important in life