Foster, Ian, Gurnell, Angela and Webb, Bruce, Sediment and water quality in river catchments     

Emilio Biagini 《GeoJournal》1998,44(2):163-165

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Application of extreme learning machine for estimation of wind speed distribution     

Shahaboddin Shamshirband  Kasra Mohammadi  Chong Wen Tong  Dalibor Petković  Emilio Porcu  Ali Mostafaeipour  Sudheer Ch  Ahmad Sedaghat 《Climate Dynamics》2016,46(5-6):1893-1907

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Some characteristics of geomagnetic reversals inferred from detailed volcanic records     

Jean-Pierre Valet  Emilio Herrero-Bervera 《Comptes Rendus Geoscience》2003,335(1):79-90

The transitional virtual geomagnetic poles (VGPs) of the five most detailed records lie within the longitudinal bands of America, western Europe and eastern Asia. This distribution does not support the hypothesis of a direct link with heterogeneities of the lower mantle underneath Americas and eastern Asia. A similar distribution of VGPs persists by adding less detailed records and show similarities with the distribution of maximum inclination anomalies predicted by time-averaged field models. However, the two databases are far too limited to infer any recurrence of non-dipole components during reversals. Clusters of VGPs are observed in most records at various geographical locations without preference for specific longitudes, which most likely result from intense volcanism during short time periods rather than from transitional dipolar states.  相似文献   

Nuovo accelerometro a massima per la componente orizzontale     

Dott.-Ing. Emilio Perri 《Pure and Applied Geophysics》1939,1(1):137-156

Riassunto Viene descritto un nuovo tipo di accelerometro a massima, dotato di pendolo elastico, e scala variabile. Si dimostra che le caratteristiche di sensibilità e funzionamento dell'apparecchio, unite al peso limitato, lo rendono principalmente adatto alla valutazione diretta delle forze sismiche massimali che possono interessare la sicurezza delle costruzioni.  相似文献   

Photosynthate allocation in a temperate sea over an annual cycle: the relationship between protein synthesis and phytoplankton physiological state     

Isabel Surez  Emilio Maran 《Journal of Sea Research》2003,50(4):285-299

The seasonal and vertical variations in the patterns of photosynthate allocation into biomolecules by natural phytoplankton assemblages were determined, together with their species composition, in a coastal station of the central Cantabrian Sea (southern Bay of Biscay). Chlorophyll-a concentration ranged from values below 20 mg m⁻² in winter to values above 80 mg m⁻² during spring and during an upwelling event in summer. Low primary production rates (<300 mgC m⁻² d^-1) were measured during winter and during summer stratification periods. The rate of C fixation during summer upwelling conditions exceeded 3500 mgC m⁻² d⁻¹. In terms of photosynthate partitioning, proteins were the dominant fraction, as they typically accounted for >30% of total photo-assimilated C, with polysaccharides and low molecular weight metabolites showing incorporation percentages around 10–30%. Relative C incorporation into lipids was generally <15%. Recurrent patterns of vertical variability in photosynthate partitioning were observed: the relative synthesis of proteins increased toward the bottom of the euphotic zone, whereas the relative C incorporation into polysaccharides and lipids tended to be higher near the surface. When primary production decreased, the synthesis of proteins was maintained more than that of other molecules. Throughout the year, the relative synthesis of proteins was inversely correlated with phytoplankton biomass, production and growth rate. The conservation of protein synthesis under growth-limiting conditions and the enhancement of lipid and polysaccharide synthesis when irradiance is high seem to constitute general patterns of photosynthate partitioning in marine phytoplankton. In our study, these patterns represented metabolic strategies of phytoplankton in response to changing environmental factors, rather than the effect of variations in the species composition of the community.  相似文献   

Effects of temporal variation of the seaweed Caulerpa prolifera cover on the associated crustacean community     

Juan Emilio Sánchez-Moyano  Isabel García-Asencio  & José Carlos García-Gómez 《Marine Ecology》2007,28(2):324-337

The aim of this study was to establish the effect of temporal variation of the alga Caulerpa prolifera cover on the composition and stability of the associated crustacean community. Forty‐five crustacean species were found, amphipods and tanaidaceans being the most abundant groups. The stations were grouped mainly based on the gradient of algal cover, independently of location or sampling period (MDS analyses). Considering separately epifaunal and infaunal species, the epifauna occurred mainly at high cover (HC) and medium–low cover (MLC) stations, while the infauna occurred at MLC and unvegetated (UV) stations. Infaunal species were predominant in all stations and sampling periods, and the abundance and numbers of epifaunal species showed a clear dependence of algal cover. To quantify the loss of biodiversity due to the plant cover variations, we applied the average and variation in taxonomic distinctness (Δ⁺ and Λ⁺, respectively). The HC stations, especially those with fewer algal cover variations along the study period, showed few fluctuations of Δ⁺,and Λ⁺ was usually located near mean; however, UV stations tended to fall in the area where the statistical power of the test is reduced and showed more oscillations of Λ⁺. The ability of these indices to test the fauna composition in function of the alga presence is discussed.  相似文献   

Reply to Comment on “Hydrodynamics of karst aquifers in metamorphic carbonate rocks: results from spring monitoring in the Apuan Alps (Tuscany,Italy)”: report published in Hydrogeology Journal (2023) 31:241–255, by Leonardo Piccini,Alessia Nannoni,and Emilio Poggetti     

Piccini  Leonardo  Nannoni  Alessia  Poggetti  Emilio 《Hydrogeology Journal》2023,31(5):1375-1377

Hydrogeology Journal -  相似文献   

Waterwells: how can we make legality more attractive?     

Foster  Stephen  Hirata  Ricardo  Custodio  Emilio 《Hydrogeology Journal》2021,29(4):1365-1368

Hydrogeology Journal - There is a pressing need to improve public administration of groundwater abstraction and use, given the global need to achieve sustainable resource exploitation and to reduce...  相似文献   

Long-Term Power Transmission Failures in Southeastern Brazil and the Geophysical Environment     

Magda A. S. Duro  Pierre Kaufmann  Fernando C. P. Bertoni  Emilio C. N. Rodrigues  José Pissolato Filho 《Surveys in Geophysics》2012,33(5):973-989

High-voltage transmission networks represent a large electrical circuit just above the ground subjected to a number of transient overcharges of various kinds, some of which may lead to failures. Some failures might be related to anomalies of the geophysical environment. We have analyzed one unprecedented long series of transmission grid failures (9?years) on high-voltage networks located in S?o Paulo state, southeastern Brazil, from 1998 to 2006, which includes an important fraction of the past solar activity cycle 23. Ninety-five distinct failure causes were given by the power line operator to explain the transmission grid shut downs. Most failures were attributed to atmospheric discharges, corresponding to 1,957 failures out of a total of 4,572 for the whole period at 138?kV, and 170 out of 763 at 440?kV, respectively. They correspond to less than one ten thousandth of the actual number of atmospheric discharges recorded in the same area, demonstrating the grid’s high resilience to breakdowns due to lightning. A clear concentration of failures in the region’s thunderstorm season has been found. A significant 67 and 77?% reduction in the number of failure rates per year has been found for the 138 and 440?kV grids, respectively, for the period studied, in good correspondence with the decay in the sunspot numbers. No obvious correlation was found between power failures and the planetary index of geomagnetic activity or major geomagnetic storms in the period, either on short or on long time scales. Assuming that the dependence of the electrosphere/ionosphere-ground coupling on the external geophysical environment plays a major role in explaining the reduction in power failures as the solar cycle wanes, it is suggested that the increase in atmosphere conductivity caused by the larger cosmic ray flux then reduces the threshold voltage required to produce lightning strokes, so reducing their effectiveness in disrupting high-voltage power lines.  相似文献   

Seasonality and anomalies of sea surface temperature off the coast of Nayarit, Mexico     

Emilio Palacios-Hernández  Laura E. Carrillo  Anatoliy Filonov  Luis Brito-Castillo  Carlos E. Cabrera-Ramos 《Ocean Dynamics》2010,60(1):81-91

Sea surface temperature (SST) harmonic and empirical orthogonal function (EOF) analyses covering 18 years were performed for the area located from 114° to 105° W and from 18° to 25° N. The results indicate that the influence of the annual signal predominates over the semi-annual signal, and the closer to the coast, the stronger the annual harmonic. Several interannual anomalies arose that are connected with the main global indexes, especially the Oceanic Niño Index. Pearson correlations between the first temporal mode of the SST and regional rainfalls in Nayarit indicate that maximum correlations (r?>?0.7) are observed when there is a +1-month lag between the series. However, this result indicates that SST is delayed with 1 month after rainfall occurrence, which shows that the dominant influence in this relationship is not the SST forcing.  相似文献