Karst springs in central-southern Italy are largely exploited for the human consumption since the Roman Times and currently feed some tens of millions inhabitants with tap water of high quality. Unlike other karst springs, they are characterized by a steady rate during the year with modest seasonal variability. However, the effects of climate changes are being strongly perceived in central and southern Italy as in the rest of the Mediterranean basin, and groundwater is obviously also affected. In this paper, we analyze the discharge time series of some important karst springs in the region, evaluating the trends and fluctuations in relation to rainfall regime, on a yearly time scale. The aim is to evaluate the response of these large karst aquifers in the Mediterranean area to the recharge input variation. The role of the North Atlantic Oscillation has also been considered. Trends and fluctuations have been highlighted by n-years moving average and transforming the time series by the Rescaled Adjusted Partial Sum. The results show that a drop in the discharge has occurred since 1987, with reductions ranging from 15 up to 30 %, although this negative trend is now possibly attenuating or even reversing. As a final remark, the spring discharge of the large karst aquifers in central-southern Italy can be assumed as a robust indicator for climate changes as it integrates the effects of precipitation and temperature variation in time and space. © 2014, Springer-Verlag Berlin Heidelberg

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The upwelling groundwater flux has been investigated by deep piezometers in a spring area characterized by alluvial deposits covering a karst substratum in Southern Italy. The piezometers are of varying depth located in a flat area. They have been monitored for a long period (about 40 years), and when measured, a good relationship between spring discharge and hydraulic head was observed. The local upwelling groundwater flux has been deducted by the increasing of the hydraulic head in depth, which allows the estimation of ascendant hydraulic gradient and groundwater velocity during the dry and wet seasons. A specific analytical solution has been used to estimate the zone involved by the ascendant flow, and could also be used in other spring areas. Some physical and chemical characteristics of spring water have been collected, including the radon (222 Rn) activity, to support the phenomenon of the ascendant flux. The man geological and hydrogeological features leading to ascendant flux in karst environments is also discussed for some areas of Southern Italy, where many springs are affected.

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The geographical distribution of concentration values for harmful elements was determined in the Campania region, Italy. The study area consists of the drainage basin of the River Calore, a tributary of the river Volturno, the largest Southern Italian river. The results provide reliable analytical data allowing a quantitative assessment of the trace element pollution threat to the ecosystem and human health. Altogether 562 stream sediment samples were collected at a sampling density of 1 site per 5 km. All samples were air-dried, sieved to <100 mesh fraction and analyzed for 37 elements after an aqua regia extraction by a combination of ICP-AES and ICP-MS. In addition to elemental analysis, gamma-ray spectrometry data were collected (a total of 562 measurements) using a hand-held Scintrex GRS-500 spectrometer. Statistical analyses were performed to show the single-element distribution and the distribution of elemental association factor scores resulting from R-mode factor analyses. Maps showing element distributions were made using GeoDAS and ArcGIS software. Our study showed that, despite evidence from concentrations of many elements for enrichment over natural background values, the spatial distribution of major and trace elements in Calore River basin is determined mostly by geogenic factors. The southwestern area of the basin highlighted an enrichment of many elements potentially harmful for human health and other living organisms (Al, Fe, K, Na, As, Cd, La, Pb, Th, Tl, U); however, these anomalies are due to the presence of pyroclastic and alkaline volcanic lithologies. Even where sedimentary lithologies occur, many harmful elements (Co, Cr, Mn, Ni) showed high concentration levels due to natural origins. Conversely, a strong heavy metal contamination (Pb, Zn, Cu, Sb, Ag, Au, Hg), due to an anthropogenic contribution, is highlighted in many areas characterized by the presence of road junctions, urban settlements and industrial areas. The enrichment factor of these elements is 3-4 times higher than the background values. The southwestern area of the basin is characterized by a moderate/high degree of contamination, just where the two busiest roads of the area run and the highest concentration of industries occurs.