Debris flows can be considered as highly hazardous hydrological processes very common in the whole Alpine environment, such as in the Friuli Venezia Giulia Region located in the extreme northeastern ...side of Italy. The progressive increase in socio-economic activities during these last years has created, in the mountain regions, the potentiality for an increased risk related to this kind of destructive phenomena. After the critical alluvial event which occurred on 21–22 June 1996 in the Fella watershed and the alluvial event of 29th August 2003 in the Val Canale valley when more than 293 mm of rain were recorded by Pontebba’s rain-gauge in four hours (the total influx of the meteorological event, which lasted about 12 h was equal to 389.6 mm) the need arose to deeply investigate the interpretation of the rainfall thresholds and on their redefinition. The analyzed examples show that there is a considerable increase in the intensity of the rainfall with a duration equal to or less than 24 hours. Above all – very critical for debris flow – are the rains of 1 to 6 hour duration having an intensity greater than 50 mm/hour.
Karst Geosites in NE Italy Cucchi, F.; Finocchiaro, F.; Zini, L.
Advances in Research in Karst Media
Book Chapter
Recenzirano
Karsts areas are “landscapes of special geological and geomorphologic interest which call for conservation” and can therefore be defined as potential geosites according to the definition given by ...Cleal et al. 2. This communication briefly describes the geological, geomorphologic and hydrogeologic features of the most important areas in North-Eastern Italy where highly karstified – both on the surface and underground – carbonate rocks outcrop. Some of them perfectly exemplify geological and geomorphologic events and their own geological history, thus serving as cultural models not only at a local but also at a global level 1. Typical examples of karst geosites are the Alpine Karst environment ofMt Canin and the Classical Karst near Trieste, as well as the Cansiglio – Cavallo Plateau, the limestone turbidites of Julian Prealps Flysch, the glaciokarst valleys of the Carnic Alps and the karren of the Devonian limestone.
Stalagmite SV1 from Grotta Savi, located at the SE margin of the European Alps (Italy), is the first Alpine speleothem that continuously spans the past c. 17kyr. Extension rate and δ18Oc record for ...the Lateglacial probably reflect a combination of temperature and rainfall, with rainfall exerting the dominant effect. Low speleothem calcite δ18 Oc values were recorded from c. 14.5 and 12.35 kyr, during GI‐1 (Bølling— Allerød) interstadial, which in our interpretation, was warm and wet. The GS‐1 (Younger Dryas) was characterized by a shift to heavier δ18 Oc, coinciding with δ13Cc enrichment and extremely low extension rate (<8 μm/year). These characteristics indicate that GS‐1 climate was cool and dry in the SE Alps. Calibration using historical data revealed that there is a positive δ18Oc/dT relationship. A 1°C rise in mean annual temperature should correspond to c. 2.85% increase of SV‐1 δc18Oc. We reconstructed a slow and steady temperature rise of c. 0.5°C since 10 kyr BP, in broad agreement with reconstructions from pollen data for SE Europe. Stalagmite SV1 indicates that climate variability in the SE Alps has been influenced by the Mediterranean Sea for the past c. 17 kyr.
Maps illustrating the different degrees of vulnerability within a given area are integral to environmental protection and management policies. The assessment of the intrinsic vulnerability of karst ...areas is difficult since the type and stage of karst development and the related underground discharge behavior are difficult to determine and quantify. Geographic Information Systems techniques are applied to the evaluation of the vulnerability of an aquifer in the alpine karst area of the Sette Comuni Plateau, in the Veneto Region of northern Italy. The water resources of the studied aquifer are of particular importance to the local communities. This aquifer must therefore be protected from both inappropriate use as well as possible pollution. The SINTACS and SINTACS P
RO K
ARST vulnerability assessment methods have been utilized here to create the vulnerability map. SINTACS P
RO K
ARST is an adaptation of the parametric managerial model (SINTACS) to karst hydrostructures. The vulnerability map reveals vast zones (81% of the analyzed areas) with a high degree of vulnerability. The presence of well-developed karst structures in these highly vulnerable areas facilitate water percolation, thereby enhancing the groundwater vulnerability risk. Only 1.5 of the studied aquifer have extremely high-vulnerability levels, however these areas include all of the major springs utilized for human consumption. This vulnerability map of the Sette Comuni Plateau aquifer is an indispensable tool for both the effective management of water resources and as support to environmental planning in the Sette Comuni Plateau area.
Some instruments that continuously measure height, temperature and conductivity of waters have been placed in 10 stations. The stations are located on the bottom of the cavities that reach the waters ...of the Timavo, the underground river that collects the hypogean waters of the Classical Karst. The preliminary analysis of the remarkable amount of data that has been collected up to now helps define the modalities of water circulation in depth better. There are three different types of flood wave, pumping effects in some tracts and mixing of different waters in other tracts.
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