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Since no extensive conceptual framework has been developed on the issues of ecosystem service (ES) and service provider (SP) in the marine environment, we have made an attempt to apply these to the conservation and management of marine biodiversity. Within this context, an accurate individuation of SPs, namely the biological component of a given ecosystem that supports human activities is fundamental. SPs are the agents responsible for making the ES-based approach operational. The application of these concepts to the marine environment should be based on an model different to the terrestrial one. In the latter, the basic model envisages a matrix of a human-altered landscape with fragments of original biodiversity; conversely, in the marine environment the model provides fragments where human activities are carried out and the matrix is represented by the original biodiversity. We have identified three main classes of ES provision: in natural, disturbed and human-controlled environments. Economic valuation of marine ESs is an essential condition for making conservation strategies financially sustainable, as it may stimulate the perceived need for investing in protection and exploitation of marine resources. 相似文献
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Phylogeography of Ophryotrocha labronica (Polychaeta,Dorvilleidae) along the Italian coasts 
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下载免费PDF全文 Piero Cossu Ferruccio Maltagliati Federica G. Pannacciulli Roberto Simonini Gloria Massamba‐N'Siala Marco Casu Claudio Lardicci Daniela Prevedelli Alberto Castelli 《Marine Ecology》2015,36(4):1088-1097
Species of the genus Ophryotrocha are a well‐studied group of organisms but, despite the relatively large body of biological studies, little is known about their intra‐specific patterns of genetic diversity. In the present study, we analysed the patterns of genetic variation in samples of Ophryotrocha labronica (Polychaeta, Dorvilleidae) collected along the Italian coasts within three regions with different thermal regimes: the Northern Adriatic Sea (NAS), the Ligurian Sea (LS), and the South/Southeast Sicilian Sea (SS). A partial sequence of the cytochrome c oxidase subunit I (COI) gene was used as a genetic marker. An analysis of molecular variance (AMOVA) showed significant genetic differentiation between the NAS and the other regions. Conversely, little or no genetic structuring was found between the LS and the SS or amongst locations within a given region. A Bayesian phylogenetic tree and a median‐joining network provided evidence for the occurrence of two highly divergent genetic lineages characterized by a high average sequence divergence (17.2%, Kimura two‐parameter distance). The spatial patterns of genetic variation found in O. labronica may reflect the signature of past expansion events of the two genetic lineages. Although the high sequence divergence suggested that cryptic speciation within O. labronica may have occurred, other traits such as the absence of reproductive isolation, pattern of phenotypic variation and habitat specificity prompted us to regard the two groups as distinct COI lineages of O. labronica. 相似文献
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Abbas Senouci Pierre Yves Bard Mohamed Naboussi Farsi Elise Beck Stéphane Cartier 《Bulletin of Earthquake Engineering》2013,11(4):1191-1215
The city of Oran is exposed to a significant seismic hazard, as almost all the northern Algeria territory, where numerous casualties and severe damage occurred in the last decades due to several moderate to large earthquakes. A mitigation policy should include the establishment of priorities to reduce the vulnerability of existing buildings based on the knowledge of the actual urban fabrics. The complexity of vulnerability assessment requires a gradual approach from the urban scale to the building scale. The study reported in this paper corresponds to the first step of such an approach, i.e., a preliminary study of the seismic vulnerability and expected damage within an urban district of the city of Oran, based on a non-dedicated data base from a building survey previously performed for other purposes. The main goals of this study are twofold: (1) an assessment of the degree of uncertainty and robustness of such results through a comparison of the results derived from different urban vulnerability methods (GNDT 2; RISK-UE LM1; and VULNERALP 2.0) and (2) an assessment of the actual level of seismic risk in the city of Oran. Cross-method comparisons and correlations highlight a satisfactory agreement between mean damage estimates at the urban scale, despite significant scattering at the single building scale, and uncertainty levels which vary significantly from one method to the other. For a given scenario, the three methods provide damage estimates lying within half an EMS damage degree of one another, with some systematic positive bias for VULNERALP and negative bias for RISK-UE LM1, especially for masonry buildings. The expected mean damage is very important for intensities 9 and 10, with an average damage grade around 3–4 for intensity 9 and 4–5 for intensity 10. The spatial distribution of damage systematically exhibits larger values in the northern, older, commercial area, than in the southern, more recent and more residential area, in relation to the building typology and the existence of several aggravating factors. Some areas of higher vulnerability / damage can be distinguished, which should receive particular attention for retrofitting priorities or urban planning decisions, also taking into account their cultural heritage value. 相似文献
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The genetic structure of the exotic ascidian Styela plicata (Tunicata) from Italian ports,with a re‐appraisal of its worldwide genetic pattern 下载免费PDF全文
下载免费PDF全文 Ferruccio Maltagliati Lisa Lupi Alberto Castelli Federica G. Pannacciulli 《Marine Ecology》2016,37(3):492-502
The pleated ascidian Styela plicata (Lesueur, 1823) is a solitary species commonly found in ports and marinas around the world. It has been recorded in the Mediterranean region since the mid‐19th century. In the present work, the species’ genetic diversity was analysed, employing a 613‐bp portion of the mitochondrial cytochrome c oxidase subunit I (COI) gene from 149 individuals collected in 14 ports along Italian coasts at spatial scales ranging from 1 to approximately 2200 km. Haplotype and nucleotide diversity values were h = 0–0.933 (total h = 0.789) and π = 0–0.145 (total π = 0.0094), respectively. A general southward trend of increasing within‐population genetic diversity was observed. Analysis of molecular variance revealed significant genetic structuring but no significant differences were detected among basins, and no isolation by distance was found. Our data were integrated with the COI sequences available from previous studies and re‐analysed in order to investigate the possible routes of introduction of this ascidian into the Mediterranean Sea. The presence of the two COI haplogroups detected in previous molecular investigations on S. plicata at intercontinental spatial scale was confirmed in the Mediterranean Sea. The results revealed multiple introductions of S. plicata, although some locations appear to have experienced rapid expansion from few founding individuals with reduced genetic diversity. However, continuous introductions would confound the pattern deriving from single founder events and make it difficult to estimate the time needed for gene diffusion into established populations. This mixing of effects creates difficulties in understanding the past and current dynamics of this introduction, and managing this alien invasive ascidian whose genetic structure is continuously shuffled by vessel‐mediated transport. 相似文献
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Salvatore Alparone Daniele Andronico Tiziana Sgroi Ferruccio Ferrari Luigi Lodato Danilo Reitano 《Natural Hazards》2007,43(3):333-350
Volcanic eruptions may create a wide range of risks in inhabited areas and, as a consequence, major economic damage to the
surrounding territory. An example of volcanic hazard was given between 1998 and 2001 by Mt. Etna volcano, in Italy, with its
frequent paroxysmal explosive activity that caused more than a hundred fire-fountain episodes. In the period January–June
2000, in particular, 64 lava fountains took place at the Southeast Crater. During the most intense explosive phase of each
episode, a sustained column often formed, reaching up to 6 km above the eruptive vent. Then, the column started to expand
laterally causing more or less copious tephra fallout on the slopes of Etna; ash and lapilli, therefore, constituted a serious
danger for vehicular and air traffic. A software and hardware warning system was developed to mitigate the volcanic hazard
indicating the areas affected by potential ash and lapilli fallout. The alert system was mainly based on the good correspondence
between the pattern of volcanic tremor amplitude and the evolution of explosive activity. When a fixed tremor threshold was
exceeded, a semiautomatic process started to send faxes to Civil Defence and Municipalities directly affected by tephra fallout,
together with information on wind directions from the Meteorological Office. The application of this methodology, during the
last 14 eruptive episodes in 2000 and the 14 events occurred in 2001, demonstrated the good correspondence between the forecasts
on the areas affected by tephra fallout and the effective tephra distribution on land. Despite the integrity of the performance
provided by the alert system, small discrepancies occurred in the technical procedure of alerting, for which possible solutions
have been discussed. The improvement of this type of system, could become basic for the Etnean region and be proposed for
similar volcanic areas throughout the world. 相似文献
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Farsi Mohammad Mohamadian Nima Ghorbani Hamzeh Wood David A. Davoodi Shadfar Moghadasi Jamshid Ahmadi Alvar Mehdi 《Natural Resources Research》2021,30(5):3455-3481
Natural Resources Research - Accurate prediction of pore-pressures in the subsurface is paramount for successful planning and drilling of oil and gas wellbores. It saves cost and time and helps to... 相似文献