6 documents found, page 1 of 1
Single events and century-scale evolution of the northern margin of the Tagus R...
Costa, A.M.; Freitas, M.C.; Inácio, M.; Fatela, F.; Lopes, V.; Andrade, C.; Cachão, M.; Mendes, P.M.; Sarrazola, A.; Macedo, M.; Bettencourt, J.In this work we present preliminary results of the study of one sediment core (EDP1), collected near Cais do Sodré, Lisbon downtown, close to the present day Tagus riverfront. The results allowed differentiation of 4 major sediment units that present a signature of increasing anthropic influence over time. The lowermost unit (Unit 1) corresponds to a subtidal flat accreting in low energy and brackish condition...
How did the AD 1755 tsunami impact on sand barriers across the southern coast o...
Costa, Pedro J. M.; Costas, Susana; González-Villanueva, R.; Oliveira, M. A.; Roelvink, D.; Andrade, C.; Freitas, M.C.; Cunha, P. P.; Martins, A.Tsunamis are highly energetic events that may destructively impact the coast. Resolving the degree of coastal resilience to tsunamis is extremely difficult and sometimes impossible. In part, our understanding is constrained by the limited number of contemporaneous examples and by the high dynamism of coastal systems. In fact, long-term changes of coastal systems can mask the evidence of past tsunamis, leaving u...
Characterization and phytoremediation of abandoned contaminated mining area in ...
Canha, N.; Freitas, M.C.; Anawar, H.M.; Dionísio, I.; Dung, H.M.; Pinto-Gomes, Carlos; Bettencourt, A.This study aims to find out a vascular plant species that accumulate relatively high concentrations of arsenic (As) for its use as phytoremediator ar abandoned and contaminated mining areas, such as São Domingos mines (Portugal). The assessement of As contamination levels in soils and plants of other similar sites in the north of the coutry (Castromil ando Poço de Freitas) was also conducted and the sample anal...
Smoke emissions from biomass burning in a Mediterranean shrubland
Alves, Célia; Gonçalves, Cátia; Pio, Casimiro; Mirante, Fátima; Caseiro, Alexandre; Tarelho, Luís; Freitas, M.C.; Viegas, D.X.Gaseous and particulate samples from the smoke from prescribed burnings of a shrub-dominated forest with some pine trees in Lousã Mountain, Portugal, in May 2008, have been collected. From the gas phase Fourier transform infrared (FTIR) measurements, an average modified combustion efficiency of 0.99 was obtained, suggesting a very strong predominance of flaming combustion. Gaseous compounds whose emissions are ...
Definition of the Portuguese frameworks with international relevance as an inpu...
Cachão, M.; Andrade, C.; Crispim, J. A.; Bilha, J.; Azerêdo, Ana C.; Barriga, F.; Cunha, P. P.; Dantas, P.; Duarte, L. V.; Freitas, M.C.; Granja, M. H.This work constitutes the first contribution for the systematisation of the geological heritage knowledge in Portugal, following the international recomendations for the characterisation of geological heritage (IUGS, ProGEO). The application of the ProGEO methodology has resulted on the creation of fourteen frameworks with international relevance, established by consensus among the Portuguese geological communi...
Late Holocene evolution of the Lower Tagus alluvial plain and heavy metals cont...
Ramos, C.; Reis, Eusébio; Ramos Pereira, A.; Azevêdo, T.M.; Nunes, E.; Freitas, M.C.; Andrade, C.This paper aims to contribute to the fluvial dynamic knowledge of the Lower Tagus during the late Holocene. Two cores were done in selected geomorphological positions at the alluvial plain. Each ten centimeters of sediments were submitted to sedimentological and geochemical analyses in order to identify human contamination by heavy metals, sedimentation rates and environmental changes in the main channel positi...