Bringing GEOSS Services into Practice: A Capacity Building Resource on Spatial Data Infrastructures (SDI)          下载免费PDF全文

Gregory Giuliani  Pierre Lacroix  Yaniss Guigoz  Roberto Roncella  Lorenzo Bigagli  Mattia Santoro  Paolo Mazzetti  Stefano Nativi  Nicolas Ray  Anthony Lehmann 《Transactions in GIS》2017,21(4):811-824

Data discoverability, accessibility, and integration are frequent barriers for scientists and a major obstacle for favorable results on environmental research. To tackle this issue, the Group on Earth Observations (GEO) is leading the development of the Global Earth Observation System of Systems (GEOSS), a voluntary effort that connects Earth Observation resources world‐wide, acting as a gateway between producers and users of environmental data. GEO recognizes the importance of capacity building and education to reach large adoption, acceptance and commitment on data sharing principles to increase the capacity to access and use Earth Observations data. This article presents “Bringing GEOSS services into practice” (BGSIP), an integrated set of teaching material and software to facilitate the publication and use of environmental data through standardized discovery, view, download, and processing services, further facilitating the registration of data into GEOSS. So far, 520 participants in 10 countries have been trained using this material, leading to numerous Spatial Data Infrastructure implementations and 1,000 tutorial downloads. This workshop lowers the entry barriers for both data providers and users, facilitates the development of technical skills, and empowers people.  相似文献   

On the reliability of the so-far performed tests for measuring the Lense–Thirring effect with the LAGEOS satellites     

Lorenzo Iorio   《New Astronomy》2005,10(8):603-615

In this paper, we critically discuss the so-far performed attempts aimed at the detection of the general relativistic gravitomagnetic Lense–Thirring effect in the gravitational field of the Earth with the existing LAGEOS satellites. In the latest reported measurement of the gravitomagnetic shift with the nodes of the LAGEOS satellites and the second generation GRACE-only EIGEN-GRACE02S Earth gravity model over an observational time span of 11 years a 5–10% total accuracy is claimed at 1–3σ, respectively. We will show that, instead, it might be 15–45% (1–3σ) if the impact of the secular variations of the even zonal harmonics is considered. Possible strategies in order both to make more robust and reliable the tests with the node-only LAGEOS–LAGEOS II combination used and to overcome the problems affecting it with other alternative combinations are presented.  相似文献   

Modelling galaxy spectra in presence of interstellar dust – I. The model of interstellar medium and the library of dusty single stellar populations     

Lorenzo Piovan  Rosaria Tantalo  Cesare Chiosi 《Monthly notices of the Royal Astronomical Society》2006,366(3):923-944

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Runoff curve numbers for steep hillslopes with natural vegetation in semi‐arid tropical highlands,northern Ethiopia     

Katrien Descheemaeker  Jean Poesen  Lorenzo Borselli  Jan Nyssen  Dirk Raes  Mitiku Haile  Bart Muys  Jozef Deckers 《水文研究》2008,22(20):4097-4105

Daily runoff from 27 plots (5 m × 2 m) recorded during two rainy seasons in the Tigray highlands (Ethiopia) were analysed together with daily rainfall to calculate runoff curve numbers for hillslopes covered by semi‐natural vegetation in varying stages of vegetation restoration. Curve number model parameters were derived using a least squares fitting procedure on the collected rainfall–runoff datasets. Curve numbers varied from 29 to 97. Land use type was an important explanatory factor for the variation in curve numbers, whereas hydrologic soil group was not. Curve numbers were negatively correlated with vegetation cover. Taking into account antecedent soil moisture conditions did not improve runoff prediction using the curve number method. As runoff prediction was less accurate in areas with low curve numbers, two separate regression functions relating curve numbers with vegetation cover were proposed for different land use types. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

What do the orbital motions of the outer planets of the Solar System tell us about the Pioneer anomaly?     

Lorenzo Iorio  Giuseppe Giudice   《New Astronomy》2006,11(8):600-607

In this paper, we investigate the effects that an anomalous acceleration as that experienced by the Pioneer spacecraft after they passed the 20 AU threshold would induce on the orbital motions of the Solar System planets placed at heliocentric distances of 20 AU or larger as Uranus, Neptune and Pluto. It turns out that such an acceleration, with a magnitude of 8.74 × 10⁻¹⁰ m s⁻², would affect their orbits with secular and short-period signals large enough to be detected according to the latest published results by E.V. Pitjeva, even by considering errors up to 30 times larger than those released. The absence of such anomalous signatures in the latest data rules out the possibility that in the region 20–40 AU of the Solar System an anomalous force field inducing a constant and radial acceleration with those characteristics affects the motion of the major planets.  相似文献   

A model-independent test of the spatial variations of the Newtonian gravitational constant in some extrasolar planetary systems     

Lorenzo Iorio 《Monthly notices of the Royal Astronomical Society》2007,376(4):1727-1730

In this paper, we directly constrain possible spatial variations of the Newtonian gravitational constant G over the range  ≈ 0.01–5 au  in various extrasolar multiplanet systems. Using the third Kepler law, we determine the quantity  Γ_XY= G _X/ G _Y  for each couple of planets X and Y located at different distances from their parent star; deviations of the measured values of Γ from unity would signal variations of G . The obtained results for  η= 1 −Γ  are found to be very compatible with zero within the experimental errors  (η/δη≈ 0.2–0.3)  . We make a comparison with an analogous test previously performed in our Solar system.  相似文献   

A stochastic inversion workflow for monitoring the distribution of CO<Subscript>2</Subscript> injected into deep saline aquifers     

Lorenzo Perozzi  Erwan Gloaguen  Bernard Giroux  Klaus Holliger 《Computational Geosciences》2016,20(6):1287-1300

We present a two-step stochastic inversion approach for monitoring the distribution of CO₂ injected into deep saline aquifers for the typical scenario of one single injection well and a database comprising a common suite of well logs as well as time-lapse vertical seismic profiling (VSP) data. In the first step, we compute several sets of stochastic models of the elastic properties using conventional sequential Gaussian co-simulations (SGCS) representing the considered reservoir before CO₂ injection. All realizations within a set of models are then iteratively combined using a modified gradual deformation algorithm aiming at reducing the mismatch between the observed and simulated VSP data. In the second step, these optimal static models then serve as input for a history matching approach using the same modified gradual deformation algorithm for minimizing the mismatch between the observed and simulated VSP data following the injection of CO₂. At each gradual deformation step, the injection and migration of CO₂ is simulated and the corresponding seismic traces are computed and compared with the observed ones. The proposed stochastic inversion approach has been tested for a realistic, and arguably particularly challenging, synthetic case study mimicking the geological environment of a potential CO₂ injection site in the Cambrian-Ordivician sedimentary sequence of the St. Lawrence platform in Southern Québec. The results demonstrate that the proposed two-step reservoir characterization approach is capable of adequately resolving and monitoring the distribution of the injected CO₂. This finds its expression in optimized models of P- and S-wave velocities, density, and porosity, which, compared to conventional stochastic reservoir models, exhibit a significantly improved structural similarity with regard to the corresponding reference models. The proposed approach is therefore expected to allow for an optimal injection forecast by using a quantitative assimilation of all available data from the appraisal stage of a CO₂ injection site.  相似文献   

A porous media finite element approach for soil instability including the second-order work criterion   总被引：1，自引：1，他引：0  

Evanthia Kakogiannou  Lorenzo Sanavia  François Nicot  Felix Darve  Bernhard A. Schrefler 《Acta Geotechnica》2016,11(4):805-825

This paper deals with the hydromechanical modelling of the initiation of failure in soils with particular reference to landslides. To this end, localized and diffused failure modes are simulated with a finite element model for coupled elasto-plastic variably saturated porous geomaterials, in which the material point instability is detected with the second-order work criterion based on Hill’s sufficient condition of stability. Three different expressions of the criterion are presented, in which the second-order work is expressed in terms of generalized effective stress, of total stress and thirdly by taking into account the hydraulic energy contribution for partially saturated materials. The above-mentioned computational framework has been applied to study two initial boundary value problems: shear failure of a plane strain compression test of globally undrained water-saturated dense sand (where cavitation occurs at strain localization) and isochoric grain matter, and the onset of a flowslide from southern Italy due to rainfall (Sarno-Quindici events, May 5–6 1998). It is shown that the second-order work criterion applied at the material point level detects the local material instability and gives a good spatial indication of the extent of the potentially unstable domains in both the localized and diffused failure mechanisms of the cases analyzed, is able to capture the instability induced by cavitation of the liquid water and gives results according to the time evolution of plastic strains and displacement rate.  相似文献   

Mycobiota associated with the rhodophyte alien species Asparagopsis taxiformis (Delile) Trevisan de Saint‐Léon in the Mediterranean Sea          下载免费PDF全文

Laura Garzoli  Giorgio Gnavi  Giovanna C. Varese  Anna M. Picco 《Marine Ecology》2015,36(4):959-968

This study is the first to investigate and characterize the mycobiota associated with the alien species Asparagopsis taxiformis, a rhodophyte classified as one of the ‘100 worst invasive species’ in the Mediterranean Sea by the Hellenic Center for Marine Research, as it threatens biodiversity. Fungal endophyte and epiphyte communities were investigated on algal specimens from two sampling sites on the island of Linosa (Marine Protected Area Isole Pelagie, Italy). 87% of the 24 specimens that were analysed for epiphytes displayed a microfungal colonization. No endophytes were found. Only a small amount of microfungi was found to be associated with this alga. Only five fungal taxa were isolated; two of which are sporadically associated with the alga, while three, Eurotium rubrum, Cladosporium cladosporioides and Cladosporium pseudocladosporioides, seem to be related to A. taxiformis. This scarcity could be related to algal chemical composition.  相似文献   

Central Mediterranean tephrochronology between 313 and 366 ka: New insights from the Fucino palaeolake sediment succession     

Niklas Leicher  Biagio Giaccio  Alison Pereira  Sebastien Nomade  Lorenzo Monaco  Giorgio Mannella  Paolo Galli  Edoardo Peronance  Danilo Mauro Palladino  Gianluca Sottili  Giovanni Zanchetta  Bernd Wagner 《Boreas: An International Journal of Quaternary Research》2023,52(2):240-271

Thirty-two tephra layers were identified in the time-interval 313–366 ka (Marine Isotope Stages 9–10) of the Quaternary lacustrine succession of the Fucino Basin, central Italy. Twenty-seven of these tephra layers yielded suitable geochemical material to explore their volcanic origins. Investigations also included the acquisition of geochemical data of some relevant, chronologically compatible proximal units from Italian volcanoes. The record contains tephra from some well-known eruptions and eruptive sequences of Roman and Roccamonfina volcanoes, such as the Magliano Romano Plinian Fall, the Orvieto–Bagnoregio Ignimbrite, the Lower White Trachytic Tuff and the Brown Leucitic Tuff. In addition, the record documents eruptions currently undescribed in proximal (i.e. near-vent) sections, suggesting a more complex history of the major eruptions of the Colli Albani, Sabatini, Vulsini and Roccamonfina volcanoes between 313 and 366 ka. Six of the investigated tephra layers were directly dated by single-crystal-fusion ⁴⁰Ar/³⁹Ar dating, providing the basis for a Bayesian age–depth model and a reassessment of the chronologies for both already known and dated eruptive units and for so far undated eruptions. The results provide a significant contribution for improving knowledge on the peri-Tyrrhenian explosive activity as well as for extending the Mediterranean tephrostratigraphical framework, which was previously based on limited proximal and distal archives for that time interval.  相似文献