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Insular mammalian fauna dynamics and paleogeography:A lesson from the western mediterranean islands

Integrative Zoology 2018年第1期13卷 2-20页

作者： Maria Rita PALOMBO Department of Earth Science Sapienza University of RomeRomaItaly CNR-IGAG Monterotondo(Roma)Italy

Since the time of Darwin(1859)and Wallace(1869),islands have been regarded by scientists as a prime target for scrutinizing the forces that may influence evolution and diversification and important elements in biogeographic *** research aims to scrutinize whether and to what extent the composition and structure of past mammal insular faunas and their changes through time may provide sound clues for inferring the paleogeographical evolution of a *** a case study,I critically analyzed the dynamics shown by the Plio-Pleistocene mammalian fauna of 3 western mediterranean insular districts,the Balearic Islands,Sardinia and Sicily,each characterized by its own peculiar paleobiogeographical evolutionary *** revision of faunas and the critical analysis of the dispersal ability of the ancestors of island settlers have allowed hypothesizing on the time and mode of island *** results obtained confirm that the early isolation of the Balearic Islands from the mainland led to the establishment of an endemic fauna since the pre-Messinian Miocene(?Astaracian European Land Mammal Age,MN7/8),and that Sardinia has definitely been isolated since the Pliocene,although dispersal events led to some faunal turnovers during the *** addition,the results suggest for Sicily a complex,still imperfectly disentangled history of alternate phases of complete separation and sporadic,more or less difficult connections with southern Italy.

关键词： dispersal islands mammal Plio–Pleistocene western mediterranean

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Mapping forest fires by nonparametric clustering analysis

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Journal of Forestry Research 2018年第1期29卷 177-185页

作者： Bulent Tutmez Mert G.Ozdogan Ahmet Boran School of Engineering Inonu University Malatya 44280Turkey Regional Directorate of Forestry Antalya 07540 Turkey

Fires have a noteworthy role to play with regards to ecological and environmental losses in mediterranean forests. In addition to ecological impacts, fire may create economic, social as well as cultural changes. The detection of fire-scars has critical importance to help decrease *** the present study, forest fires recorded in Antalya, one of the most important ecological and tourist regions within the western mediterranean, were clustered and mapped. Since the dominant factors and devastation records derived from the cases had nominal-scaled properties, a categorical databased nonparametric clustering algorithm was performed in this evaluation. The proposed tool, k-modes algorithm,uses modes instead of means for clustering. The algorithm may be implemented quickly and does not make distributional assumptions concerning the available data. It uses a frequency-based method to update the modes of the *** derived modes from the maps may be useful information for local authorities to manage. In conclusion, the proposed nonparametric clustering procedure may be employed to build a decision-support system to monitor and identify fire activities and to enhance fire management efficiency.

关键词： Forest fire Categorical variable Clustering western mediterranean

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A seismological evidence for the northwestward movement of Africa with respect to Iberia from shear-wave splitting

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Geoscience Frontiers 2012年第5期3卷 681-696页

作者： Mohamed K.Salah Geology Department Faculty of Science Tanta UniversityTanta 31527Egypt

Seismic anisotropy and its main features along the convergent boundary between Africa and Iberia are detected through the analysis of teleseismic shear-wave splitting. Waveform data generated by 95 teleseismic events recorded at 17 broadband stations deployed in the western mediterranean region are used in the present study. Although the station coverage is not uniform in the Iberian Peninsula and north- west Africa, significant variations in the fast polarization directions and delay times are observed at stations located at different tectonic domains. Fast polarization directions are oriented predominantly NW-SE at most stations which are close to the plate boundary and in central Iberia; being consistent with the absolute plate motion in the region. In the northern part of the Iberian Peninsula, fast velocity direc- tions are oriented nearly E--W; coincident with previous results. Few stations located slightly north of the plate boundary and to the southeast of lberia show E--W to NE-SW fast velocity directions, which may be related to the Alpine Orogeny and the extension direction in lberia. Delay times vary significantly between 0.2 and 1.9 s for individual measurements, reflecting a highly anisotropic structure beneath the recording stations. The relative motion between Africa and lberia represents the main reason for the observed NW-SE orientations of the fast velocity directions. However, different causes of anisotropy have also to be considered to explain the wide range of the splitting pattern observed in the western mediterranean region. Many geophysical observations such as the low Pn velocity, lower lithospheric Q values, higher heat flow and the presence of high conductive features support the mantle flow in the western mediterranean, which may contribute and even modify the splitting pattern beneath the studied region.

关键词： Shear-wave splitting Seismic anisotropy Iberian Peninsula Northwest Africa western mediterranean

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