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Il poster illustra le prime elaborazioni GIS relative alla fisiografia, al paleoambiente e alla collocazione dei siti Paleolitici nei Colli Berici e ai loro margini.

Le aree carsiche italiane rappresentano il 18% del territorio nazionale e forniscono risorse idropotabili valutabili in oltre il 25% del totale. L'idrodinamica e l'idrochimica egli acquiferi carisci è assolutamente peculiare e necessita di specifici protocolli per poter essere da un lato studiati e dall'altro salvaguardati per conservarne inalterate le risorse di acqua potabile.

Sono presentati e discussi alcuni dei principali risultati del progetto di ricerca nazionale (PRIN). Speleotemi di alcune grotte scelte dell’Italia settentrionale, centrale e meridionale sono stati studiati con diverse tecniche e datati in spettrometria di massa con il metodo U/Th. In generale, la velocità di accrescimento dopo aver raggiunto una massima velocità durante la prima parte dell’Olocene decresce sensibilmente. Si può notare come esista un’interrelazione tra temperatura media della grotta e velocità di accrescimento. I cambiamenti del δ13C mostrano un trend generalmente negativo, soprattutto durante il Tardiglaciale e la prima parte dell’Olocene. Soltanto durante gli ultimi 2 ka si nota un’inversione verso valori tendenzialmente positivi. I cambiamenti nel δ18O degli speleotemi delle grotte Savi (TS) e Frasassi (AN) mostrano un trend prevalentemente positivo durante l’Olocene (valori compresi tra -5 e -10 ‰); al contrario il trend della stalagmite delle Grotta di Carburangeli (PA) è negativo. La luminescenza eccitata da laser degli speleotemi della grotta Savi mostra i suoi massimi nella prima parte dell’Olocene, probabilmente in relazione con lo sviluppo di suoli forestali. I valori più bassi sono quelli degli ultimi 1,5 ka. Da uno sguardo d’insieme, i dati sono in accordo con le conoscenze sui cambiamenti climatici in Italia durante il Tardiglaciale e l’Olocene. Emergono tuttavia alcuni dati problematici che suggeriscono ulteriori ricerche. Some of the main result of a national research project (PRIN) are here presented and discussed. The speleothems of some selected caves of northern, central and southern Italy have been studied with different techniques and dated by U/Th mass spectrometry. In general, the growth rate shows a decrease during the middle and upper Holocene in all caves. A relationship between the annual growth rate and the cave mean annual temperatures seems evident. The δ13C changes show a generally negative trend, with a main slope during the Lateglacial and the fi rst part of Holocene. Only during the last 2 ka an inversion towards more positive values is occurring. The δ18O changes of the speleothems from Savi (TS) and Frasassi (AN) cave, show a mainly positive trend during the Holocene (range of values between -5 and -10‰); on the contrary the trend of Carburangeli cave (PA) stalagmite is negative. The laser induced luminescence of the spelothems of Savi cave shows the highest values during the fi rst part of the Holocene probably infl uenced by the soil and forest development. The lowest values are those of the last 1.5 ka. From an overall view, these data seem to fi t with the present day knowledge of the climatic and environmental changes of Italy. Nevertheless some problematic aspects arise suggesting further research work.

The reconstruction of the clymatic cycles characterizing the North Italy during Holovene and Late Pleistocene has been obtained fom the luminescence analyses of a speleothem from Savi Cave near Trieste. The longest luminescence record covers the last 14430+/- 176 years.

Viene presentata una disamina delle conoscenze attuali sulle acque ospitate in acquiferi carsici in Italia anche e sopratutto in realzione all'interazione tra attività umane e acquiferi dalla preistoria ai giorni nostri. Viene puntualizzata l'importanza strategica che queste acque rivestono sopratutto per un loro futuro impiego come risorse idropotabili. Infine si puntualizzano i principali problemi connessi alla loro salvaguardia e utilizzo.

Since a couple of years, the Italian Speleological Society (SSI) is carrying out a project for the realisation of a national inventory of Hypogean Natural Geosites (Geositi Ipogei Naturali = GIN). A GIN can be defined as "every subterranean natural void that represents exceptional naturalistic and/or cultural value, in the widest sense, in at least one of the following features: its intrinsic characteristics, its geological, geomorphologic or hydrogeological context, its morphodynamic significance, its content of hypogean landscape elements or significant materials, that allow palaeo-environmental reconstructions, or, finally, for the use Man has made of it in time". The exceptionality mostly regards the scientific interest of the already performed or potential researches (global, European, national, regional or local relevance of the acquired or acquirable information), the historical and cultural interest and elements such as beauty, dimension, rarity, representativity and didactic or cultural interest. As a GIN, entire cave complexes, single caves or single passages of caves can be chosen. Five types of GIN have been identified. GIN for the intrinsic characteristics of the cave: concerns particularly well preserved parts of caves and their morphologies (erosion and corrosion forms), but also caves derived from particular speleogenetic processes (e.g. hyperkarst caves) or formed in special types of rock (e.g. gypsum caves). GIN for the interest of the hosting karst area: in this type caves with no special interest but representing important karst areas can be inserted. GIN for the nature of the outcropping rocks: regroups caves that allow a better understanding of petrography, mineralogy, tectonics, stratigraphy or palaeontology of the area. GIN for the material contained in them: concerns caves with scientifically important sediments, speleothems, evidences of palaeo-seismicity, palaeo-environmental indicators, archaeological or palaeontological deposits. GIN for the importance in Man's history: contains caves used by Man in prehistory, but also the ones used more recently as places of cult, or caves important for the development of the speleological and karst explorations and studies. For all these types of GIN that also can coexist in the same site the exceptional conditions of the phenomena have to be maintained, having different scales ranging from local up to global importance. A first list of Italian GIN has been compiled by a Working Group that has been instituted by the Italian Speleological Society, composed of the Regional Responsibles of the Cave Registers and several experts. For every Italian region no more than 1% of the total amount of natural caves has been identified as GIN. In this paper a preliminary overview of some Italian GIN is given, reporting their names, distribution, type and importance. This provisional list already shows the exceptionality of the Italian hypogean heritage on a European and global scale and these results encourage the Working Group to continue this research that aims for a better understanding and a growth of public awareness of this incredible speleological heritage.

High-resolution luminescence speleothem records from Savi Cave, Trieste, NE Italy - We measured three luminescent records from the sample SV1, a stalagmite from Savi Cave (Trieste karst, Italy). The longest panoramic record (having the lowest resolution from the records) is a proxy of the solar infl uence on the climatic system and covers last 14430±176 years. The step of the record varies from 1.1 to 12.7 years. First composite record, which consists of 81000 data points, is compiled of 39 overlapping scans. It covers the last 5005±140 years. The time step of the record varies from 9.9 days to 33.9 days. The highest resolution record covers last 2028±100 years and allows precise determination of growth rate of the stalagmite. It consists of 40106 data points compiled of 16 overlapping scans. Its time step varies from 15.6 days to 19.9 days. We made a reconstruction of the annual growth rate variations for the last 2028 years, which represents annual precipitation for this region.

Grotta Savi, which opens on the flanks of Monte Stena in Rosandra Valley (Carso Triestino, Italy), consists in a network of sub-horizontal galleries developed from 300 to 350 meters a.s.l., and a total extension of >4 km. SV1 stalagmite, which comes from the inner part of the cave, is the first European speleothem that spans continuously the last 17 ka. Eighteen MC-ICPMS U/Th method datings were obtained from the 27 cm tall stalagmite, and 345 stable isotope analyses were carried out along its growth axis (mean resolution: 50±43 yrs). The stalagmite began to growth at 16.8±0.51 ka, and the axial growth rate was very low (below 10 µm/yr) until the end of the Younger Dryas From ~10.67 to ~7.59 ka a faster axial growth rate was recorded (30 to 44 µm/yr). The δ18O record reflects the amount of water that fed the stalagmite, which depends on mean annual rainfall amount and by the evapotranspiration at the surface. The δ18O record is positively correlated with the same record from Soreq Cave in Israel (BAR-MATTHEWS ET AL., 1997), and inversely with the 18O record of GISP2 ice core (GROOTES ET AL., 1993). For the more recent part of SV1, we observed a positive correlation between δ18O-calcite and the reconstructed mean annual temperature for the last 500 years in the Alps (LUTERBACHER ET AL. 2004). The strong temperature increase between 1800 AD and today is replicated by the positive δ18O trend in SV1.

Sulla parte più recente (72 cm) di una carota assiale estratta da una grossa stalagmite ancora in formazione nel sistema carsico “Grotta del Fiume - Grotta Grande del Vento” (Gola di Frasassi, Ancona) sono state effettuate datazioni col metodo MC-ICPMS U/Th, analisi isotopiche di O e C e uno studio petrografi co. La parte più antica della carota (da 104 a 72 cm dal top), caratterizzata da elevata porosità e tracce di dissoluzione, non è stata analizzata. L’analisi petrografi a ha rivelato che la stalagmite è costituita quasi interamente da calcite “colonnare allungata”. A 11 mm dalla sommità della concrezione, si osserva un marcato passaggio tessiturale da colonnare allungata (sotto) a dendritica (sopra). Le datazioni hanno permesso di stabilire che lo speleotema ha iniziato a formarsi prima del Dryas Recente, con tasso medio di accrescimento di 227 μm/anno tra 9,63±1,06 e 8,84±0,49 ka e una successiva brusca diminuzione a 51 μm/anno tra 8,60±0,34 e 5,35±0,37, cui fanno seguito tassi di crescita tra 23 e 31 μm/anno per i restanti 5350 anni. Si nota una tendenza positiva del δ18O dall’inizio alla fi ne del concrezionamento (da -8,0‰ a -7,2‰) interrotto da due singoli picchi negativi a 3,6 ka e 2,0 ka, evidenziati anche nel record del δ13C. L’andamento del δ18O potrebbe rispecchiare un graduale riscaldamento da 12 ka ad oggi, oppure essere legato ad una progressiva diminuzione della piovosità media annua, con conseguente arricchimento nell’isotopo pesante nella zona di evaporazione (Mediterraneo Orientale), analogamente a quanto evidenziato nella Grotta di Soreq (Israele). Il trend generale del profi lo del δ13C è negativo fi no a circa 2 ka (da -5,8‰ a -9,5‰), mentre gli ultimi 2000 anni sono caratterizzati da un aumento del δ13C fi no al valore attuale di -5,07‰. In particolare, si osserva un arricchimento molto rapido di quasi il 2‰ tra il 1200 e il 1350 AD che riporta i valori medi del δ13C a quelli tipici dell’Olocene inferiore e Dryas Recente. Una tendenza verso valori più alti in entrambi i profi li isotopici contraddistingue gli ultimi 300-400 anni circa ed è verosimilmente legata ad attività antropiche (deforestazione, trasformazione a pascolo ecc.). Il forte incremento registrato nelle ultime due analisi del record del δ13C, che si accompagna alla variazione tessiturale prima menzionata, potrebbe testimoniare un aumento nella circolazione dell’aria in grotta a seguito della realizzazione di una galleria artifi ciale per l’ingresso dei visitatori. MC-ICPMS U/Th dating, oxygen and carbon isotopic determinations and petrographic investigations have been performed on the upper portion (72 cm) of a core, axially drilled from a large, actively growing stalagmite in “Grotta del Fiume - Grotta Grande del Vento” karst system (Frasassi Gorge, Ancona). The younger portion of the core (from 104 to 72 cm from the top), characterised by a relevant porosity with traces of dissolution, has not been analysed. The petrographic study has shown that the stalagmite almost completely consists of “elongated columnar” calcite. At 11 mm from the top there is clear evidence of a marked textural change from “elongated columnar” to dendritic. The stalagmite started to form before the Younger Dryas with an average growing rate of 227 μm/a between 9.63±1.06 and 8.84±0.49 ka and a later abrupt decrease down to 51 μm/a from 8.60±0.34 to 5.35±0.37 ka, followed by rates of 23 and 31 μm/a for the remaining 5350 years. A positive δ18O trend is evident along the axial growth axis of the speleothem (from -8.0‰ to -7.2‰), interrupted by two single negative peaks at 3.6 ka and 2.0 ka, also found in the δ13C record. The δ18O trend could be connected with a gradual warming from 12 ka up to the present times, or with a progressive decrease of the average annual precipitation and a consequent enrichment in the heavy isotope in the evaporation area (Eastern Mediterranean), as recorded at Soreq Cave (Israel). The general δ13C trend is negative until 2 ka (from -5.8‰ to -9.5‰), whereas the last 2 ka are characterised by an increase of δ13C up to the present value of -5.07‰. In particular, a very rapid increase of about 2‰ is evident from 1200 to 1350 AD, reaching the values typical of the Lower Holocene and the Younger Dryas. An increasing trend in both the isotopic records characterises the last 300-400 years and is probably due to anthropic activities. The strong increase measured in the last two δ13C analyses, connected with the above mentioned textural change, could testify for an increase of air circulation in the cave triggered by the opening of an artifi cial tunnel for the entrance of visitors.