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271.
Luís Margalho Raquel Menezes Inês Sousa 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(5):1307-1321
In Europe, since 1990, a survey on environmental monitoring has been taking place every 5 years, using moss samples to study the distribution of heavy metal concentration and assess contamination sources, resulting on the identification of statistical association of several heavy metal concentrations in mosses. With this work, we propose an extension of an existing spatio-temporal model, introduced in Høst et al. (JASA 90(431):853–861, 1995), allowing for prediction at unsampled locations of pollution data in the presence of covariates related to each country specificities, when separately modelling the spatial mean field, the spatial variance field and the space–time residual field. Moreover, this model allows to estimate an interpolation error, as an accuracy measure, derived dependently on the case study. For a validation purpose, a simulation study is conducted, showing that the use of the proposed model leads to more accurate prediction values. Results obtained by the proposed methodology for the most recent available survey, are compared with results obtained with no temporal information, namely when Ordinary Kriging, according to the definition in Cressie (Statistics for spatial data, Wiley, New York, 1993), is used to derive illustrative prediction maps based only on the most recent data. An exercise of cross-validation is performed relative to each of the scenarios considered and the average interpolation errors are presented. While assessing interpolation errors, we conclude that the monitoring specificities of each country and the information of preceding surveys allow for more accurate prediction results. 相似文献
272.
Gabriel Granco Marcellus Marques Caldas Jason Scott Bergtold Ana Claudia Sant’Anna 《GeoJournal》2017,82(1):63-80
Within the past decade, the sugarcane ethanol industry in Brazil has increased its production capacity to meet rising domestic demand for ethanol. However, to achieve this growth the industry has had to expand into new frontiers in the Brazilian Cerrado, specifically in the states of Goiás and Mato Grosso do Sul, which is now the second largest producing area of ethanol in Brazil. We argue that the expansion into the Brazilian Cerrado is a result of the interactions between the increase in demand, governmental policies, infrastructure, and factors that have prevented traditional sugarcane producing regions from meeting the increasing demand for ethanol. This paper analyzes the policies that have shaped the sugarcane industry in Brazil and the expansion of the industry across the country. The policies and issues examined include those that led to the concentration and consolidation of the sugarcane industry in the state of São Paulo and the consequences of this consolidation; the influence of governmental policies on the decision-making process of producers and industry; the state-level policies designed to expand the industry into Goiás and Mato Grosso do Sul states; infrastructure development; and the Sugarcane Agroecological Zoning policies. Through this study we conclude that the ethanol industry identified the Cerrado states as an opportunity for investment, given the good agricultural conditions for producing sugarcane, affordable land prices and favorable state-level fiscal incentive policies. In addition, there is a need for further regional development policies as the interaction between the sugarcane sector and regional government is likely to continue into the future. 相似文献
273.
Sedimentological and benthic foraminifera analyses carried out on a core (length 4.15 m, collected at 22°56′31″S and 41°58′48″W, at a water depth of 43 m) sampled from the inner shelf of Cabo Frio, southeastern Brazilian continental margin, allowed identification of different hydrodynamic and productivity regimes related to sea-level fluctuations and/or climatic changes, during the last 9.4 ka cal BP. Prior to 7.0 ka cal BP, a less intense hydrodynamic and lower productivity regime occurred at lower sea levels and under drier climatic conditions. Between 7.0 and 5.0 ka cal BP, relatively stronger local oceanic circulation and relatively high productivity were observed, in a scenario of rising sea levels and more humid conditions. From 5.0 to 3.0 ka cal BP, bottom currents weakened and input of nutrients increased, with productivity levels similar to the previous phase at lower sea level and in a drier climate. From 3.0 ka cal BP up to the present, stronger hydrodynamic conditions and a higher productivity regime are linked to the establishment of the upwelling process in Cabo Frio. From 2.5 ka cal BP to the present, upwelling enhancement has been recognized, resulting from the combined action of NE winds and the intensification of the meandering pattern of the Brazil Current (BC). 相似文献
274.
Leoncio García-Barrón Julia Morales Arturo Sousa 《Theoretical and Applied Climatology》2013,114(3-4):445-457
Variability in precipitation affects annual total records and causes instability in rainfall distribution throughout the year. Our aim in this study was to develop a procedure, based on pluviometric centralisation and dispersion parameters, that is able to characterise rainfall distribution throughout a year of precipitation in a unique, condensed and precise manner. This enabled the evolution of intra-annual precipitation from 1837 to 2010 in the southwest of the Iberian Peninsula to be determined. The obtained results showed irregular oscillations of the parameters during the selected period. Specifically, patterns of precipitation in recent decades revealed the following differentiating features: the displacement of the most intense rainy periods in autumn with a consequent decrease in precipitation in spring, and more erratic distribution throughout the year with an increase of the frequency of intra-annual dispersion peaks. 相似文献
275.
GPS Solutions - In addition to traditional tide gauges, the ground-based global navigation satellite system reflectometry (GNSS-R) that utilizes signal-to-noise ratio data from a single GNSS... 相似文献
276.
The tectonic system of the eastern flank of Mt. Etna volcano (Sicily, Italy) is the source of most of the strongest earthquakes occurring in the area over the last 205 years. A total of 12 events with epicentre intensities ≥VIII EMS have occurred at Mt. Etna, 10 of which were located on the eastern flank. This indicates a mean recurrence time of about 20 years. This area is highly urbanised, with many villages around the volcano at altitudes up to 700 m a.s.l. The southern and eastern flanks are particularly highly populated areas, with numerous villages very close to each other. The probabilistic seismic hazard due to local faults for Mt. Etna was calculated by adopting a site approach to seismic hazard assessment. Only the site histories of local volcano-tectonic earthquakes were considered, leaving out the effects due to strong regional earthquakes that occurred in north-eastern and south-eastern Sicily. The inventory used in this application refers to residential buildings. These data were extracted from the 1991 census of the Italian National Institute of Statistics, and are grouped according to the census sections. The seismic vulnerability of the elements at risk belonging to a given building typology is described by a vulnerability index, in accordance with a damage model based on macroseismic intensities. For the estimation of economic losses due to physical damage to buildings, an integrated impact indicator was used, which is equivalent to the lost building volume. The expected annualised economic earthquake losses were evaluated both in absolute and in relative terms, and were compared with the geographical distribution of seismic hazard and with similar evaluations of losses for other regions. 相似文献
277.
da Silva Glauciene Justino Ferreira de Oliveira Nádja Melo Santos Celso Augusto Guimarães da Silva Richarde Marques 《Natural Hazards》2020,102(3):965-965
Natural Hazards - This correction stands to support the updating of the original article for changing the name Glauciene Justino Ferreira to Glauciene Justino Ferreira da Silva. The author group... 相似文献
278.
Martins I Lopes RJ Lillebø AI Neto JM Pardal MA Ferreira JG Marques JC 《Marine pollution bulletin》2007,54(6):678-690
A spatially dynamic model for the productivity of spores and adults of green macroalgae (Enteromorpha sp.) was developed for a mesotidal estuary (Mondego estuary, Portugal). Many of the algal processes and parameters included in the model were experimentally obtained. Model predictions were compared to a real time series (1993-1997) of macroalgal biomass variation and the two sets show a good agreement (ANOVA, P<0.001). Results suggest that algal growth is highly sensitive to small changes in depth and exhibits different patterns of variation in different seasons. On a yearly basis, global calculations for the south channel of the estuary (137 ha) suggest that during bloom years, macroalgal biomass may reach about 21,205 ton DW compared to 240 ton DW in regular years. On a seasonal basis, the difference may be even more significant. The consequences of such variations on the nitrogen and phosphorus loading of the system and the adjacent coastal area are discussed. 相似文献
279.
W.J. Chaplin T. Appourchaux T. Arentoft J. Ballot J. Christensen‐Dalsgaard O.L. Creevey Y. Elsworth S.T. Fletcher R.A. García G. Houdek S.J. Jimnez‐Reyes H. Kjeldsen R. New C. Rgulo D. Salabert T. Sekii S.G. Sousa T. Toutain the rest of the asteroFLAG group 《Astronomische Nachrichten》2008,329(5):549-557
We report on initial results from the first phase of Exercise #1 of the asteroFLAG hare and hounds. The asteroFLAG group is helping to prepare for the asteroseismology component of NASA's Kepler mission, and the first phase of Exercise #1 is concerned with testing extraction of estimates of the large and small frequency spacings of the low‐degree p modes from Kepler‐like artificial data. These seismic frequency spacings will provide key input for complementing the exoplanet search data. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献