Investigating the time dynamics of geoelectrical signals measured in two seismotectonic environments in the Mediterranean region: the Southern Apennine chain (Southern Italy) and the Hellenic arc (Crete Island, Greece)

Abstract. Multifractal fluctuations in the time dynamics of geoelectrical data, recorded in a seismic area of southern Italy, have been revealed using the Multifractal Detrended Fluctuation Analysis (MF-DFA), which allows to detect multifractality in nonstationary signals. Our findings show that the geoelectrical time series, recorded in the seismic area of southern Apennine Chain (Italy), is multifractal. The time evolution of the multifractality suggests that the multifractal degree increases prior the occurrence of earthquakes. This study aims to propose another approach to investigate the complex dynamics of earthquake-related geoelectrical signals.

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Principal component analysis of geoelectrical signals measured in the seismically active area of Basilicata Region (southern Italy)

Natural Hazards and Earth System Science ◽

10.5194/nhess-4-663-2004 ◽

2004 ◽

Vol 4 (5/6) ◽

pp. 663-667 ◽

Cited By ~ 9

Author(s):

L. Telesca ◽

G. Colangelo ◽

K. Hattori ◽

V. Lapenna

Keyword(s):

Principal Component Analysis ◽

Southern Italy ◽

Principal Component ◽

Component Analysis ◽

Stress And Strain ◽

Short Term ◽

Time Dynamics ◽

Basilicata Region ◽

Heterogeneous Nature ◽

Geoelectrical Signals

Abstract. Geoelectrical fluctuations are the end product of several geophysical phenomena. In particular geoelectrical signals measured in seismically active areas can be attributed to stress and strain changes, associated with earthquakes. The complexity of this problem has suggested the development of advanced statistical methods to investigate the heterogeneous nature of these fluctuations. In this paper we analysed the time dynamics of short-term variability of geoelectrical field measured at Giuliano station, located in Basilicata Region, one of the most seismically active areas of southern Italy. We applied the principal component analysis (PCA). The analysis has shown earthquake precursory patterns in the daily variation of the principal components, revealing that the PCA approach is promising for monitoring seismic areas.

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Cyclones in the Mediterranean region: present and future climate scenarios derived from a general circulation model (HadAM3P)

Advances in Geosciences ◽

10.5194/adgeo-7-9-2006 ◽

2006 ◽

Vol 7 ◽

pp. 9-14 ◽

Cited By ~ 26

Author(s):

Chr. Anagnostopoulou ◽

K. Tolika ◽

H. Flocas ◽

P. Maheras

Keyword(s):

General Circulation Model ◽

Mediterranean Region ◽

General Circulation ◽

Atmospheric General Circulation Model ◽

Southern Italy ◽

Circulation Model ◽

Cyclonic Activity ◽

Climate Scenarios ◽

Atmospheric General Circulation ◽

The Mediterranean

Abstract. In this paper, an attempt is made to assess and evaluate the skill of the Hadley Center atmospheric General Circulation Model (HadAM3P) in generating successfully the frequency and intensity of severe cyclones (<1000 hPa) in the Mediterranean region. The cyclonic occurrence is studied in three regions of enhanced cyclonic activity: Gulf of Genoa, Southern Italy and Cyprus. It was found that the HadAM3P predicts a future decrease of the frequency of the severe cyclones at the SLP level, but the future cyclones will be more intense (deeper), especially at the 500 hPa level.

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Twig and Shoot Dieback of Citrus, a New Disease Caused by Colletotrichum Species

Cells ◽

10.3390/cells10020449 ◽

2021 ◽

Vol 10 (2) ◽

pp. 449

Author(s):

Mario Riolo ◽

Francesco Aloi ◽

Antonella Pane ◽

Magdalena Cara ◽

Santa Olga Cacciola

Keyword(s):

Mediterranean Region ◽

Colletotrichum Gloeosporioides ◽

Southern Italy ◽

Sweet Orange ◽

First Report ◽

Colletotrichum Species ◽

Rdna Its ◽

Citrus Groves ◽

Dieback Disease ◽

The Mediterranean

(1) Background: This study was aimed at identifying the Colletotrichum species associated with twig and shoot dieback of citrus, a new syndrome occurring in the Mediterranean region and also reported as emerging in California. (2) Methods: Overall, 119 Colletotrichum isolates were characterized. They were recovered from symptomatic trees of sweet orange, mandarin and mandarin-like fruits during a survey of citrus groves in Albania and Sicily (southern Italy). (3) Results: The isolates were grouped into two distinct morphotypes. The grouping of isolates was supported by phylogenetic sequence analysis of two genetic markers, the internal transcribed spacer regions of rDNA (ITS) and β-tubulin (TUB2). The groups were identified as Colletotrichum gloeosporioides and C. karstii, respectively. The former accounted for more than 91% of isolates, while the latter was retrieved only occasionally in Sicily. Both species induced symptoms on artificially wound inoculated twigs. C. gloeosporioides was more aggressive than of C. karstii. Winds and prolonged drought were the factor predisposing to Colletotrichum twig and shoot dieback. (4) Conclusions: This is the first report of C. gloeosporioides and C. karstii as causal agents of twig and shoot dieback disease in the Mediterranean region and the first report of C. gloeosporioides as a citrus pathogen in Albania.

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