41 research outputs found

    High resolution agriculture land cover using aerial digital photography and GIS : a case study for small island states

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    Chapter 7With the advent of site-specific crop management, sustainability and profitability, land farming now requires information and technology-based management system to identify, analyse and manage spatial and temporal resource variability. Th is approach is being made increasingly possible by recent innovation in information technologies such as mobile devices, geographic information systems, positioning technologies (such as Geographical Position system), and Earth Observations. Such innovation now off ers a holistic approach to micro-manage agricultural resources. (Robert et al., 1994). Basic mapping and farm-level record keeping is one of the first precision agriculture practices that must be implemented in a typical productive agriculture operation (Stombaugh et al., 2001). Typical tasks include mapping of variations that occur in largescale field features such as vegetation stress, crop rotation, inventorying, irrigation, soil drainage and erosion, pest control, etc. Th e search for a low cost methodology that takes into account the growth of information technology in data capture and surveying, data processing, database creation and geographic information systems becomes mandatory in order to respond to such needs. Th e study constitutes, for the first time in Malta, the collection of high precision farming statistics that makes use of an inexpensive system for aerial mapping that requires minimal ground truthing. Th e effectiveness of such a method for small areas was later demonstrated by Galdies and Borg (2006) related to coastal and beach management in the Maltese islands. In the current case, digital aerial remote sensing enabled the accurate mapping of agricultural variables, and coupled with ground survey data, resulted in the production of precise, high resolution agricultural crop-cover maps. Additional information can be further derived from this data that can be used for the optimisation of micro agriculture practices.peer-reviewe

    A preliminary report on the marine Macrobenthos and the Demersal fish fauna of the island of Filfla (Maltese Islands, Central Mediterranean)

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    The nature, distribution, and abundance of the main component species of the supralittoral, mediolittoral and upper infralittoral marine macrobenthic assemblages of Filfla were studied during a series of expeditions to the islet between 1990 and J 994. The demersal fish fauna was censused by direct observation. The distribution of sponges was studied along two 2m-wide belt transects laid along a gently sloping and a steep sloping bottom, respectively. In general, the same type of benthic assemblages as found on other exposed rocky coasts in the Maltese Islands occurred at Filfla. However, at Filfla, the littoral zones were compressed, and species richness and abundance in the littoral and sublittoral were generally low compared to other exposed rocky shores in the Maltese Islands. In spite of the extensive infralittoral sandy bottoms present at Filfla, no sea-grass meadows were encountered. Most of these differences are probably attributable to the high exposure, the extensive boulder shores and submarine boulder fields that surround the islet, and to bottom turbulence. Large differences in species composition and abundance of sponges were found between the two transects. Crambe crambe and Agelas oroides were the most abundant sponges on the steep bottom, while Sarcotragus spinosula was the most abundant species on the more gently sloping one. Compared to that of mainland sites, the demersal fish fauna of Filfla was impoverished in terms of both species richness and abundance.peer-reviewe

    High Resolution Agriculture Land Cover Using Aerial Digital Photography and GIS: A Case Study for Small Island States

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    Introduction With the advent of site-specifi c crop management, sustainability and profi tability, land farming now requires information and technology-based management system to identify, analyse and manage spatial and temporal resource variability. Th is approach is being made increasingly possible by recent innovation in information technologies such as mobile devices, geographic information systems, positioning technologies (such as Geographical Position system), and Earth Observations. Such innovation now off ers a holistic approach to micro-manage agricultural resources. Th e study constitutes, for the fi rst time in Malta, the collection of high precision farming statistics that makes use of an inexpensive system for aerial mapping that requires minimal ground truthing. Th e eff ectiveness of such a method for small areas was later demonstrated b

    Seismic noise cross-correlation in the urban area of Benevento city (Southern Italy)

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    This article has been accepted for publication in Geophysical Journal International ©: The Authors 2019. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. Uploaded in accordance with the publisher's self-archiving policy.In the last decade the use of passive methods has become appealing in reconstructing the properties of the propagation medium by seismic ambient noise data, without the use of localized natural or artificial sources. A temporary seismic network was installed in the urban area of Benevento (southern Italy) in order to characterize the shallow structure of the city using stable methods for the analysis of the seismic noise continuously acquired by stations. The city of Benevento is one of the italian areas with highest seismic hazard, and at present the region is affected by low energy swarms and sparse events (Ml ≤ 4.1). It has been struck by several destructive historical earthquakes, the strongest of which occurred in 1456, 1688, 1805 with associated MCS intensity up to X–XI. We used the sixteen seismic stations installed in Benevento to record ambient noise for about 1 month. The stations were equipped with different seismic instruments: (i) digitizers Quanterra Q330 connected to Le3d-5 s short-period sensors; (ii) Nanometrics Centaur digitizers coupled with Trillium Compact 120s broad-band velocimeters; (iii) one station with Episensor force balance accelerometer connected to a D6BB-DIN Staneo digitizer. Interstations Green's functions were reconstructed by the cross-correlation of continuous ambient noise data, and surface waves signals were extracted from Green's Functions (GFs) for investigating the elastic properties of the subsurface structure. In this regard, we performed the beamforming analysis to test the hypothesis of isotropy distribution of noise sources on which the cross-correlation method is based, and the particle motion analysis to confirm the presence of surface Rayleigh waves in the GFs. We analysed the temporal stability of the cross-correlated signals and the results show that 2 weeks of continuous measurements are sufficient to stabilize the surface waves signal extracted from the GFs. The phase velocity dispersion curves are computed for 115 station pairs through the use of a far-field representation of the surface-wave GFs and an image transformation technique. Our strategy based on cross-correlation analysis provides robust phase-velocity dispersion curves that vary approximately from 1.4 km s–1 at 0.7 Hz to 0.6 km s–1 at 5 Hz. Different pairs were selected for the inversion of phase-velocity dispersion curves aimed to derive 1-D shear-wave velocity (Vs) profiles (up to a maximum depth of about 500 m) representative of some areas of the city characterized by different soil deposits.Published1524–15425T. Sismologia, geofisica e geologia per l'ingegneria sismicaJCR Journa

    Temporary dense seismic network during the 2016 Central Italy seismic emergency for microzonation studies

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    In August 2016, a magnitude 6.0 earthquake struck Central Italy, starting a devastating seismic sequence, aggravated by other two events of magnitude 5.9 and 6.5, respectively. After the first mainshock, four Italian institutions installed a dense temporary network of 50 seismic stations in an area of 260 km2. The network was registered in the International Federation of Digital Seismograph Networks with the code 3A and quoted with a Digital Object Identifier ( https://doi.org/10.13127/SD/ku7Xm12Yy9 ). Raw data were converted into the standard binary miniSEED format, and organized in a structured archive. Then, data quality and completeness were checked, and all the relevant information was used for creating the metadata volumes. Finally, the 99 Gb of continuous seismic data and metadata were uploaded into the INGV node of the European Integrated Data Archive repository. Their use was regulated by a Memorandum of Understanding between the institutions. After an embargo period, the data are now available for many different seismological studies.Publishedid 1825T. Sismologia, geofisica e geologia per l'ingegneria sismicaJCR Journa

    Gruppo Operativo Emersito++ Evento Sismico Ischia 2017: Campagne Di Misure Geofisiche, Rapporto N°1

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    Rapporto Tecnico n°1 della task force operativa EMERSITO++ (INGV) che descrive le campagne sismiche ed elettromagnetiche condotte nei comuni di Casamicciola Terme e di Lacco Ameno a seguito del terremoto di Ischia del 21 Agosto 2017.INGVPublished4T. Sismologia, geofisica e geologia per l'ingegneria sismica1SR. TERREMOTI - Servizi e ricerca per la SocietàN/A or not JC

    Sperimentazione di un apparecchio multifunzionale in etĂ  pediatrica

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    Low shear velocity in a normal fault system imaged by ambient noise cross correlation: The case of the Irpinia fault zone, Southern Italy

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    We extracted the Green's functions from cross correlation of ambient noise recorded at broadband stations located across the Apennine belt, Southern Italy. Continuous records at 26 seismic stations acquired for 3 years were analyzed. We found the emergence of surface waves in the whole range of the investigated distances (10\u2013140 km) with energy confined in the frequency band 0.04\u20130.09 Hz. This phase reproduces Rayleigh waves generated by earthquakes in the same frequency range. Arrival time of Rayleigh waves was picked at all the couples of stations to obtain the average group velocity along the path connecting the two stations. The picks were inverted in separated frequency bands to get group velocity maps then used to obtain an S wave velocity model. Penetration depth of the model ranges between 12 and 25 km, depending on the velocity values and on the depth of the interfaces, here associated to strong velocity gradients. We found a low-velocity anomaly in the region bounded by the two main faults that generated the 1980, M 6.9 Irpinia earthquake. A second anomaly was retrieved in the southeast part of the region and can be ascribed to a reminiscence of the Adria slab under the Apennine Chain

    Utilizzo del lip bumper nella gestione dello spazio nei settori posteriori.

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