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111.
Liu  Xudong  Zhang  Ran  Feng  Jia  Rindi  Fabio  Xie  Shulian 《中国海洋湖沼学报》2021,39(6):2370-2379
Journal of Oceanology and Limnology - The genus Neglectella Vodenicarov & Benderliev has a morphology similar to the well-known genus Oocystis, except for the numerous chloroplasts stacked...  相似文献   
112.
This paper investigates the impact of soil moisture-temperature feedback during heatwaves occurring over France between 1989 and 2008. Two simulations of the weather research and forecasting regional model have been analysed, with two different land-surface models. One resolves the hydrology and is able to simulate summer dryness, while the other prescribes constant and high soil moisture and hence no soil moisture deficit. The sensitivity analysis conducted for all heatwave episodes highlights different soil moisture-temperature responses (1) over low-elevation plains, (2) over mountains and (3) over coastal regions. In the plains, soil moisture deficit induces less evapotranspiration and higher sensible heat flux. This has the effect of heating the planetary boundary layer and at the same time of creating a general condition of higher convective instability and a slight increase of shallow cloud cover. A positive feedback is created which increases the temperature anomaly during the heatwaves. In mountainous regions, enhanced heat fluxes over dry soil reinforce upslope winds producing strong vertical motion over the mountain slope, first triggered by thermal convection. This, jointly to the instability conditions, favors convection triggering and produces clouds and precipitation over the mountains, reducing the temperature anomaly. In coastal regions, dry soil enhances land/sea thermal contrast, strengthening sea-breeze circulation and moist cold marine air advection. This damps the magnitude of the heatwave temperature anomaly in coastal areas, expecially near the Mediterranean coast. Hence, along with heating in the plains, soil dryness can also have a significant cooling effect over mountains and coastal regions due to meso-scale circulations.  相似文献   
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On 27 February 2007, a new eruption occurred on Stromboli which lasted until 2 April. It was characterized by effusive activity on the Sciara del Fuoco and by a paroxysmal event (15 March). This crisis represented an opportunity for us to refine the model that had been developed previously (2002–2003 eruption) and to improve our understanding of the relationship between the magmatic dynamics of the volcano and the geochemical variations in the fluids. In particular, the evaluation of the dynamic equilibrium between the volatiles (CO2 and SO2) released from the magma and the corresponding fluids discharged from the summit area allowed us to evaluate the level of criticality of the volcanic activity. One of the major accomplishments of this study is a 4-year database of summit soil CO2 flux on the basis of which we define the thresholds (low–medium–high) for this parameter that are empirically based on the natural volcanological evolution of Stromboli. The SO2 fluxes of the degassing plume and the CO2 fluxes emitted from the soil at Pizzo Sopra la Fossa are also presented. It is noteworthy that geochemical signals of volcanic unrest have been clearly identified before, during and after the effusive activity. These signals were found almost simultaneously in the degassing plume (SO2 flux) and in soil degassing (CO2 flux) at the summit, although the two degassing processes are shown to be clearly different. The interpretation of the results will be useful for future volcanic surveillance at Stromboli.  相似文献   
115.
On April 6, 2009 a ML = 5.8 earthquake hit the city of L’Aquila on the Apennine chain in central Italy. Notwithstanding the moderate-size event the L’Aquila city and several small villages along the Aterno river valley suffered severe damage, because of the unusual strong motions, mainly due to proximity to the fault (estimated hypocentral depth of about 10 km). In this paper the main features of the recorded motion are discussed. Four accelerometric stations were located within the surface projection of the fault and recorded peak values ranging from 0.4 to 0.6 g. The recorded motions were characterised by short durations and high peak accelerations both in the horizontal and vertical directions. The strong portions of vertical and horizontal motions occurred almost simultaneously due to the short travel paths of P and S waves from the fault to the ground surface near the fault area. Hence site response analyses were performed for the sites where recording stations were located. The geotechnical subsoil model was derived by boreholes, in situ dynamic tests (D-H and SDMT) and by laboratory tests (RCT). One-dimensional numerical analyses were carried out employing the well known computer code EERA. The numerical model was calibrated, in the linear equivalent range, by comparing numerical results with the horizontal acceleration recorded components.  相似文献   
116.
Overview of the Italian strong motion database ITACA 1.0   总被引:3,自引:2,他引:1  
The Italian Strong Motion Database, ITACA, was developed within projects S6 and S4, funded in the framework of the agreements between the Italian Department of Civil Protection (Dipartimento della Protezione Civile, DPC) and the Istituto Nazionale di Geofisica e Vulcanologia (INGV), starting from 2005. The alpha version of the database was released in 2007 and subsequently upgraded to version 1.0 after: (i) including the most recent strong motion data (from 2005 to 2007) recorded in Italy, in addition to the 2008 Parma earthquake, M 5.4, and the M ≥  4.0, 2009 Abruzzo seismic events; (ii) processing the raw strong motion data using an updated procedure; (iii) increasing the number of stations with a measured shear wave velocity profile; (iv) improving the utilities to retrieve time series and ground motion parameters; (v) implementing a tool for selecting time series in agreement with design-response spectra; (vi) compiling detailed station reports containing miscellaneous information such as photo, maps and site parameters; (vii) developing procedures for the automatic generation of station reports and for the updating of the header files. After such improvements, ITACA 1.0 was published at the web site , in 2010. It presently contains 3,955 three-component waveforms, comprising the most complete catalogue of the Italian accelerometric records in the period 1972–2007 (3,562 records) and the strongest events in the period 2008–2009. Records were mainly acquired by DPC through its Accelerometric National Network (RAN) and, in few cases, by local networks and temporary stations or networks. This paper introduces the published version of the Italian Strong Motion database (ITACA version 1.0) together with main improvements and new functionalities.  相似文献   
117.
The aim of this paper is to disseminate knowledge in the seismic science community about a possible tool which is not largely popular, despite its potential usefulness. In this paper it will be shown how satellite remotely sensed images may represent a powerful source of information where traditional sources of information are unable to deliver it, or at least to do so timely. Even when traditional information flow can ensure delivery, an advantage may still be found in terms of sooner availability and smaller amount of labour required. In the case shown here a vulnerability study was made on a vast industrial area in the gulf of Siracusa, Sicily, Italy. A series of concurrent factors made it particularly troublesome to obtain information on the structures found in the site (tanks, pipes, chimneys, roads, ...), required to suitably carry out the study. Satellite images were then acquired to obtain the information needed. Processing of the images was carried out relying on in-house software formerly developed for similar information extraction issues, and integrated with new, specifically developed elements, some pieces of information were obtained useful for seismic risk evaluation. In particular, location, footprint, elevation of significant structures (e.g. tanks, chimneys) could be evaluated, obtaining results in a format compatible with the most widespread GIS (Geographic Information System) standards. Such compatibility allowed a considerable savings on labour time required to lay a GIS of the area, which is a fundamental tool for risk and vulnerability analyses.  相似文献   
118.
This work summarizes the results of a geomorphological and bivariate statistical approach to gully erosion susceptibility mapping in the Turbolo stream catchment (northern Calabria, Italy). An inventory map of gully erosion landforms of the area has been obtained by detailed field survey and air photograph interpretation. Lithology, land use, slope, aspect, plan curvature, stream power index, topographical wetness index and length-slope factor were assumed as gully erosion predisposing factors. In order to estimate and validate gully erosion susceptibility, the mapped gully areas were divided in two groups using a random partitions strategy. One group (training set) was used to prepare the susceptibility map, using a bivariate statistical analysis (Information Value method) in GIS environment, while the second group (validation set) to validate the susceptibility map, using the success and prediction rate curves. The validation results showed satisfactory agreement between the susceptibility map and the existing data on gully areas locations; therefore, over 88% of the gullies of the validation set are correctly classified falling in high and very high susceptibility areas. The susceptibility map, produced using a methodology that is easy to apply and to update, represents a useful tool for sustainable planning, conservation and protection of land from gully processes. Therefore, this methodology can be used to assess gully erosion susceptibility in other areas of Calabria, as well as in other regions, especially in the Mediterranean area, that have similar morphoclimatic features and sensitivity to concentrated erosion.  相似文献   
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Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献   
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