Correction to: Cultural heritage and earthquakes: bridging the gap between geophysics,archaeoseismology and engineering

Journal of Seismology -     

通过对调查数据的趋势和多变量分析确定宏观场

通过多变(相关分析)和趋势分析等统计方法对宏观调查数据进行了解释.这种方法使我们通过评定不同宏观效应叠加的程度、估计调查数据的不确定性更客观地评定烈度.通过滤波确定烈度场的区域分量,使我们消除观测中的局部变化.给出了选取适当滤波参数的准则.本文应用这一方法对发生在意大利的一次地震的调查数据进行了处理.     

Isolation by distance, gene flow and phylogeography in the Proasellus coxalis-group (Crustacea, Isopoda) in Central Italy: allozyme data

Fifteen populations belonging to the Proasellus coxalis-group were surveyed for genetic variation at 19 enzymatic loci in order to clarify the degree of genetic structuring of this species at the scale of Central Italy. With Neighbour-Joining analysis, it was possible to identify two main clusters, the first grouping populations sampled in coastal areas of Central Italy, the second comprising several populations from inland areas of the Apennines. In the first group, genetic relationships follow a geographic scheme, with populations arranged according to the proximity of the collecting sites. The inland populations have less clear geographic relationships and a higher degree of genetic differentiation. In view of the paleogeography of the study areas, I hypothesise a more recent penetration of this taxon into the Central Italian alluvial coastal plains (subjected to cyclical marine ingressions during the Quaternary) from sources of colonisation in the inland areas. The higher genetic differentiation of the inland populations presumably reflects a longer evolutionary history and could be explained by the periodic fragmentation of river catchments during Pleistocene climatic fluctuations. Such an evolutionary scenario is supported by F-statistics analyses. Effective dispersal of individuals between populations can be hypothesised for the coastal populations but not for the inland ones. On the whole, there is a pattern of isolation by distance, but a large amount of gene flow seems to reflect historical rather than ongoing gene exchange.     

Depth and Seasonal Distribution of Some Groups of the Vagile Fauna of the Posidonia oceanica Leaf Stratum: Structural and Trophic Analyses

Abstract. The taxonomical and trophic structures of the vagile fauna communities of the leaf stratum in a Posidonia oceanica meadow at Ischia (Gulf of Naples, Italy) were investigated at five stations along a depth gradient (1 to 25 m). Sampling was performed in July, November, February, and May. The analyzed groups - polychaetes, molluscs, tanaids, isopods, amphipods, and decapods - exhibited similar distributional trends in all seasons, with coenotic discontinuities occurring at well-defined depths. The same zonation pattern was produced by feeding-guild analysis. Eleven trophic groups were identified. The most abundant groups were: Herbivores, which were found mainly at the shallow stations; Herbivores-deposit feeders, which were widely distributed along the transect; Deposit feeders-carnivores, found mainly at the deep stations.
This study suggests that in the Posidonia leaf stratum, herbivores and herbivores-deposit feeders, as consumers of epiphytic micro- and macroflora and deposited particulate organic matter, play an important role in the energy transfer from producers to higher trophic levels of the system.     

Web-based macroseismic survey in Italy: method validation and results

A new method of macroseismic surveys, based on voluntary collaboration through the Internet, has been running at the Istituto Nazionale di Geofisica e Vulcanologia (INGV) since July 2007. The macroseismic questionnaire is addressed to a single non-specialist; reported effects are statistically analysed to extrapolate a probabilistic estimate of Mercalli Cancani Sieberg and European Macroseismic Scale intensities for that observer. Maps of macroseismic intensity are displayed online in almost real time and are continuously updated when new data are made available. For densely inhabited zones, we have received reports of felt effects for even very small events (M = 2). Six earthquakes are presented here, showing the ability of the method to give fast and interesting results. The effects reported in questionnaires coming from three towns are carefully analysed and assigned intensities are compared with those derived from traditional macroseismic surveys, showing the reliability of our web-based method.     

Adiabatic chaos in the spin–orbit problem

We provide evidences that the angular momentum of a symmetric rigid body in a spin–orbit resonance can perform large scale chaotic motions on time scales which increase polynomially with the inverse of the oblateness of the body. This kind of irregular precession appears as soon as the orbit of the center of mass is non-circular and the angular momentum of the body is far from the principal directions with minimum (maximum) moment of inertia. We also provide a quantitative explanation of these facts by using the theory of adiabatic invariants, and we provide numerical applications to the cases of the 1:1 and 1:2 spin–orbit resonances.