FAOSTAT estimates of greenhouse gas emissions from biomass and peat fires     

Simone Rossi  Francesco N. Tubiello  Paolo Prosperi  Mirella Salvatore  Heather Jacobs  Riccardo Biancalani  Joanna I. House  Luigi Boschetti 《Climatic change》2016,135(3-4):699-711

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Erratum to: FAOSTAT estimates of greenhouse gas emissions from biomass and peat fires     

Simone Rossi  Francesco N. Tubiello  Paolo Prosperi  Mirella Salvatore  Heather Jacobs  Riccardo Biancalani  Joanna I. House  Luigi Boschetti 《Climatic change》2016,135(3-4):713-713

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Observed changes in the Earth’s dynamic oblateness from GRACE data and geophysical models     

Y. Sun  P. Ditmar  R. Riva 《Journal of Geodesy》2016,90(1):81-89

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Monitoring of a methane-seeping pockmark by cabled benthic observatory (Patras Gulf, Greece)     

Giuditta Marinaro  Giuseppe Etiope  Nadia Lo Bue  Paolo Favali  George Papatheodorou  Dimitris Christodoulou  Flavio Furlan  Francesco Gasparoni  George Ferentinos  Michel Masson  Jean-François Rolin 《Geo-Marine Letters》2006,26(5):297-302

A new seafloor observatory, the gas monitoring module (GMM), has been developed for continuous and long-term measurements of methane and hydrogen sulphide concentrations in seawater, integrated with temperature (T), pressure (P) and conductivity data at the seafloor. GMM was deployed in April 2004 within an active gas-bearing pockmark in the Gulf of Patras (Greece), at a water depth of 42 m. Through a submarine cable linked to an onshore station, it was possible to remotely check, via direct phone connection, GMM functioning and to receive data in near-real time. Recordings were carried out in two consecutive campaigns over the periods April–July 2004, and September 2004–January 2005, amounting to a combined dataset of ca. 6.5 months. This represents the first long-term monitoring ever done on gas leakage from pockmarks by means of CH₄+H₂S+T+P sensors. The results show frequent T and P drops associated with gas peaks, more than 60 events in 6.5 months, likely due to intermittent, pulsation-like seepage. Decreases in temperature in the order of 0.1–1°C (up to 1.7°C) below an ambient T of ca. 17°C (annual average) were associated with short-lived pulses (10–60 min) of increased CH₄+H₂S concentrations. This seepage “pulsation” can either be an active process driven by pressure build-up in the pockmark sediments, or a passive fluid release due to hydrostatic pressure drops induced by bottom currents cascading into the pockmark depression. Redundancy and comparison of data from different sensors were fundamental to interpret subtle proxy signals of temperature and pressure which would not be understood using only one sensor.  相似文献   

Caisson breakwaters embodying an OWC with a small opening—Part II: A small-scale field experiment     

Paolo Boccotti  Pasquale Filianoti  Vincenzo Fiamma  Felice Arena 《Ocean Engineering》2007,34(5-6):820-841

A common and intuitive idea is that, before an absorbing breakwater, waves are smaller than before a conventional reflecting breakwater. The theory of Part I has shown that, on the contrary, before a breakwater converter, in some cases, the wave height may be greater than before a conventional reflecting breakwater. Now, an experiment off the eastern coast of the Straits of Messina provides a confirmation of the theory: some huge amplifications of swells are common at a breakwater converter, and as a consequence the energy absorption gets very large. Here, we show the results of the experiment, and, basing ourselves on these results and on the theory of Part I, we suggest some practical way of calculation.  相似文献   

Determination of heavy metals in fresh and sea waters of S. Rossore Park (PISA)     

Maria Betti  Maria Perla Colombini  Roger Fuoco  Paolo Papoff 《Marine Chemistry》1985,17(4):313-322

A study was performed in the Tyrrhenian Sea in front of S. Rossore Park (Pisa) to ascertain the degree of Cu, Pb, Cd and Cr pollution and to investigate whether the rivers flowing into the sea may be considered potential sources of seawater contamination. Owing to the variability of such a system, the research, covering a one-year period, involved five surveys on 13 selected sampling stations and two surveys following the floats along the river Arno and its plume. The results refer to the total concentration of the above metals in the water phase after filtration. The content of Cu, Pb and Cd was always found to be higher than in the reference station (about 8 km offshore), generally reaching maximum values around the mouths of the rivers. Concentrations exceeding the minimal risk concentration were observed in the case of Cd. As for Cr, its concentration was always below the detection limit of the analytical method used. Rivers thus appear to be the main sources of coastal metal pollution.By the samplings carried out along the river Arno and its plume (involving 3–5 km from the mouth), it was found that the dilution model represents the concentration pattern for Cu and Pb fairly well over a large range of salinity.  相似文献   

Changes in storminess and surges in western France during the last century     

Paolo Antonio Pirazzoli  Herv Regnauld  Loïc Lemasson 《Marine Geology》2004,210(1-4):307-323

French meteorological data provide some information on wind direction since 1890. Since 1951, wind speed and direction have been digitised every three hours in many stations. The Brest tide gauge has recorded hourly sea levels since 1860, thus enabling hourly surges to be calculated and studied. This set of data has been organised into a data base and analysed in order to recognize evolution and trends. Strong winds are increasing in frequency in the western part of Brittany and decreasing in Normandy and Pays de Loire. Surges associated with these winds do present a slight decreasing trend. A more precise analysis allows to distinguish between southerly winds, which are slightly decreasing, and strong winds from other directions, which display a more or less important increase in frequency. The analysis shows trends that may be linked to the global circulation pattern, and that result in a new spatial distribution of winds on western France.  相似文献   

The Lago di Varano: Hydrologic Characteristics and Sediment Composition     

Federico Spagnoli  Antonietta Specchiulli  Tommaso Scirocco  Gerardo Carapella  Paolo Villani  Giovanni Casolino  Primiano Schiavone  Massimo Franchi 《Marine Ecology》2002,23(S1):384-394

Abstract. The Lago di Varano is situated on the north side of the Gargano National Park (southeast Italy) and covers a surface area of about 65 km². It communicates with the Adriatic Sea through two artificial canals (Foce Capoiale and Foce Varano) located at the two ends of a long and narrow coastal dune. This work presents preliminary results of four seasonal surveys (1999–2000) carried out to measure chemical and physical parameters of the water column (temperature, salinity, dissolved oxygen and pH) and to analyse a number of biogeochemical characteristics of surface sediments (organic matter, total phosphorus, total nitrogen and total Hg, As, Pb, Cd, Cr, Cu and Ni content). Water analysis indicated poor exchange between the coastal pond and the open sea, limited to autumn and winter. Surface sediments were rich in organic matter, whose distribution was influenced by chemical-physical and hydrodynamic variations in the water column. At the sediment level, the highest values of Cd were found in the central zone of the basin, while the highest Cr values were measured in the central and southeastern areas. With the exception of Cd and Pb, the metal content did not indicate anthropogenic pollution, in particular when compared with the Venice Lagoon and the Central Adriatic Sea.  相似文献   

A field experiment on the small-scale model of a gravity offshore platform     

Paolo Boccotti   《Ocean Engineering》1995,22(6)

The 1:50 scale model of a big offshore gravity platform was placed off the beach at Reggio-Calabria, where the wind waves typically have significant height ranging from 0.20 to 0.40 m and peak period from 1.8 to 2.6 sec. A first set of pressure transducers was assembled at the boundary of the platform and a second set, with the same configuration as the first one, was assembled in the undisturbed wave field, in order to compare the force amplitude on the platform to the force amplitude on an ideal equivalent mass of water (Froude-Krylov force amplitude). Along with the pressure transducers, a few wave gauges were functioning in the undisturbed wave field. It was found that the time histories of the pressure induced by the highest waves, at the columns and at the platform base, were very similar to the measured covariances of the pressure fluctuations. The statistical distribution of the forces on the platform proved to be coincident with the statistical distribution of the Froude-Krylov forces. The spectrum of the force process proved always to be narrow even in the case of the broad wave spectrum. The diffraction coefficient (ratio of the actual force amplitude to the Froude-Krylov force amplitude) was found to depend essentially on a marked reduction of the propagation speed of the pressure head waves, both at the columns and at the platform base.  相似文献   

Temporal Dynamics and Biomass Partitioning in Three Adriatic Seagrass Species: Posidonia oceanica,Cymodocea nodosa,Zostera marina     

Paolo Guidetti  Maurizio Lorenti  Maria&#x;Cristina Buia  Lucia Mazzella 《Marine Ecology》2002,23(1):51-67

Abstract. The temporal dynamics of three seagrasses, Posidonia oceanica, Cymodocea nodosa and Zostera marina, was studied in different areas of the Adriatic Sea by analysing phenological parameters and biomass trends in different compartments of seagrass systems. For this purpose, samplings were conducted in 1997 once per season at each station, Otranto (southern Adriatic Sea) and Grado (northern Adriatic Sea). Structural parameters and biomass of plant compartments differed among seagrasses both in absolute values and in seasonal variability. P. oceanica was the largest plant, showing the highest number of leaves per shoot, highest leaf surface, Leaf Area Index and shoot weight. Z. marina was intermediate in size and had the longest leaves, whereas C. nodosa was the smallest seagrass. P. oceanica accounted for the highest total biomass (mean ± SE: 1895.9 ± 180.2 g DW · m^–2; CV = coefficient of variation: 19.0 %), considerably more than C. nodosa (mean ± SE: 410.4 ± 88.4 g DW·m^–2; CV: 43.1 %) and Z. marina (mean ± SE: 312.1 ± 75.1 g DW · m^–2; CV: 48.1 %), although the two latter species displayed a higher seasonal variability. Similarly, other features, such as shoot density, leaf surface, LAI, shoot weight and relative contributions of above‐ and below‐ground compartments, were less variable across seasons in P. oceanica than in the two other seagrasses, while leaf length showed the highest seasonal fluctuation in P. oceanica. As for biomass partitioning, C. nodosa showed a higher proportion of the below‐ground relative to above‐ground biomass (up to 90 %), with a distinct seasonality, whereas in P. oceanica the proportion of below‐ground biomass (around 80 %) was fairly constant during the year. We infer that in P. oceanica the seasonal forcing is probably buffered by the availability of internal resources stored permanently during the year in the below‐ground. In C. nodosa and Z. marina, instead, growth processes seem to be amplified by a greater influence of environmental factors.  相似文献