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- Sarcocornia fruticosa and Spartina maritima as heavy metals remediators in an European southwestern salt marsh (Ria Formosa, Portugal)Publication . F. G. M. Silva, Manuela; Aníbal, J.; Duarte, Duarte; Chícharo, LuísSalt marshes are transition zones between land and sea, exposed to several sources of different pollutants, including heavy metals, which tend to be accumulated in sediments. Halophyte vegetation which colonises sediments affects retention and biovailability of the pollutants that reach salt marsh areas. The accumulation capacity and the pattern of metal distribution in salt marsh plant tissues vary among plant species, and with sediment characteristics. The aim of this study was to survey the behaviour of Spartina maritima and Sarcocornia fruticosa on heavy metals contents and distribution amongst sediment and plant tissues in an European Southwestern lagoon (Ria Formosa, Portugal). Both species could fix metals from the surrounding belowground environment and accumulate them mainly in roots (and in rhizomes for S. maritima). Metal translocation to aerial organs was residual. S. maritima acted as a more effective metal stabiliser than S. fruticosa.
- Understanding paleolithic human coastal adaptations in southwetern Iberian Peninsula (Paleocoast Project)Publication . Marreiros, Joao; Duarte, D. N.; Regala, Frederico; Dores, Tiago; Francisco, Rui; Soares, RicardoThe geological and geomorphological formations in the Atlantic shore of Southern Portugal in Algarve are characterized by karstic formations. Karstic features, such as natural caves and shelters, have long been seen as an attractive ecological and geological landscape to early human occupation during the Pleistocene and Early Holocene. The project PaleoCoast, Paleolithic Human Coastal Adaptations in Southwestern Iberian Peninsula, aims to locate and identify coastal karst formation, and assess its speleological and geological characterization, and archaeological potential. This poster introduces the PaleoCoast research project, including research scope, goals and methods, and an overview on the preliminary results from the pilot study conducted in 2017.
- Metal contamination in Ria Formosa saltmarsh sediments and halophyte vegetationPublication . Silva, Manuela; Duarte, Duarte; Chicharo, LuisSaltmarsh vegetation may retain certain substances from anthropogenic activities in surrounding areas, providing a control of contaminants such as heavy metals, coming from industry, agriculture and urbanization. In the last decades there are been na increase in urbanization and industrialization of the area surrounding Marim – Ria Formosa, where this study was performed.
- Integrated approach to assess ecosystem health in harbor areasPublication . Bebianno, Maria João; Pereira, C.; Rey, F.; Cravo, Alexandra; Duarte, D. N.; D'Errico, G.; Regoli, F.Harbors are critical environments with strategic economic importance but with potential environmental impact: health assessment criteria are a key issue. An ecosystem health status approach was carried out in Portimão harbor as a case-study. Priority and specific chemical levels in sediments along with their bioavailability in mussels, bioassays and a wide array of biomarkers were integrated in a biomarker index (IBR index) and the overall data in a weight of evidence (WOE) model. Metals, PAHs, PCBs and HCB were not particularly high compared with sediment guidelines and standards for dredging. Bioavailability was evident for Cd, Cu and Zn. Biomarkers proved more sensitive namely changes of antioxidant responses, metallothioneins and vittellogenin-like proteins. IBR index indicated that site 4 was the most impacted area. Assessment of the health status by WOE approach highlighted the importance of integrating sediment chemistry, bioaccumulation, biomarkers and bioassays and revealed that despite some disturbance in the harbor area, there was also an impact of urban effluents from upstream.
- The role of Spartina maritima and Sarcocornia fruticosa on trace metals retention in Ria Formosa, PortugalPublication . Moreira, Manuela M.; Duarte, Duarte; MGP Isidoro, Jorge; Chícharo, LuísOver the last years, phytoremediation has become an increasingly recognized pathway for contaminant removal from water and shallow soils. Assessing the phytoremediation potential of wetlands is complex due to variable conditions of hydrology, soil/sediment types, plant species diversity, growing season and water chemistry. Physico-chemical properties of wetlands provide many positive attributes for remediating contaminants. Saltmarsh plants can sequestrate and inherently tolerate high metal concentrations found in saltmarsh sediments.
- Postglacial sea-level rise and sedimentar response in the Guadiana Estuary, Portugal/Spain borderPublication . Boski, T.; Moura, Delminda; Veiga-Pires, C.; Camacho, Sarita; Duarte, Duarte; Scott, David; Fernandes, SandroThe study of sedimentological features, foraminifera and molluscan fauna in samples recovered from four rotary boreholes permitted, after 14C dating, the first assessment of the post-glacial transgression in Guadiana River Estuary. The Holocene sequence is underlain by coarse sediments from delta fan enclosing continental swamp deposits dated 16980 year BP. The Holocene sedimentary sequence was deposited either directly on this delta fan gravels or on top of fluvial sands deposited probably between 11000 and 10000 yr BP. An accelerated phase of the estuary infilling by clayey sediments containing the saltmarsh foraminifer Trochammina, began ca. 9800 year BP, when sea level was about 39 m below present. Between 7500 and 7000 year BP, the central part of the estuary started to accommodate coarser sediments, partially introduced from the continental shelf. The first phase of Holocene sea-level rise at a rate of 0.85 m/century terminated ca. 6500 year BP. Since then, lagoonal sediments in the vicinity of the estuary have been enclosed behind sand spits and predominantly sandy sedimentation was initiated within the estuary. After a second phase of slower rise at the rate of 0.3 m/century, which lasted until ca. 5000 year BP, the sea approached the present level.
- A hidrodinâmica e o transporte sedimentar no estuário do Rio MondegoPublication . Duarte, Duarte; Boski, T.; Reis, Rui Paulo Bento Pena dos; Dias, João Manuel AlveirinhoEsta dissertação teve por principal objectivo o estudo da hidrodinâmica e do transporte sedimentar de fundo no estuário do Mondego, através da caracterização dos processos de mistura, estratificação e da circulação nos principais canais do estuário. Avaliaram-se os impactes das obras de regularização do braço norte. A fisiografia regularizada do braço norte facilitou a circulação dos escoamentos fluviais ao longo do canal principal, e favoreceu a entrada da maré para o interior do estuário em resultado da redução significativa do atrito de fundo deste canal, que por sua vez se traduziu numa entrada de sedimentos marinhos localizados no seu sector distal. A propagação da maré no canal principal foi definida por um domínio da enchente, com um comportamento hipo-síncrono, estacionário com uma pequena componente progressiva. Aquando de maiores caudais do Mondego, passou a definir um domínio de vazante e uma distorção estacionária+progressiva+fluvial. No braço sul apresentou-se praticamente estacionária e foi caracterizada por uma ligeira tendência evolutiva de domínio de vazante e por um comportamento hipso-síncrono. Nos regimes bem misturados e dominados pela maré, a resultante do transporte sedimentar de fundo tendeu a fazer-se para dentro do estuário, enquanto nos quadros muito estratificados processou-se inversamente.
- Postglacial sea-level rise in South Portugal as recorded in Guadiana EstuaryPublication . Boski, T.; Moura, Delminda; Camacho, Sarita; Duarte, Duarte; Scott, David; Veiga-Pires, C.; Pedro, Paulo; Santana, PauloThe Guadiana River Estuary is located in the terminal part of a deeply incised river valley, which accumulated several tens of meters of sediments during the Holocenic transgression. Five cored boreholes (see Fig.1 for localisation) that reached the pre-Holocenic substratum were drilled recently in order to recognize the architecture of sedimentary facies and to quantify the accumulation of organic carbon trapped in sediments during the valley infilling by marine waters. It was assumed that due to structural constraints imposed by Palaeozoic and Mezozoic substratum, the main estuarine channel did not change its position significantly. Consequently borehole locations were chosen in order to represent different sedimentary environments in the estuary: proximity to the main channel (CM1 and CM3), external sea facing (CM4) and lagoonal (CM2 and CM5) environments.
- Preenchimento sedimentar em três estuários do Algarve durante o HolocénicoPublication . Boski, T.; Moura, Delminda; Veiga-Pires, C.; Duarte, Duarte; Santana, Paulo; Pedro, PauloAs bacias hidrográficas são distintas quer do ponto de vista hidrológico quer na forma e àrea de captação.
- Modelo de maturação de processos em Instituições de Ensino SuperiorPublication . Duarte, Duarte; Martins, Paula VenturaA adopção de estratégias de melhoria de processos de negócio é actualmente uma procupação de qualquer organização. Os benefícios desta melhoria na optimização dos recursos e na capacidade de resposta das organizações tem suscitado diversas propostas de metodologias de melhoria de processos. Estas diferem quer nos princípios que as suportam, quer na área específica a que se destinam. No entanto, são ainda escassas as propostas e os resultados de investigação científica acerca da melhoria de processos em instituições de ensino superior, extremamente complexas e com características únicas. Este projecto de investigação pretende propôr a extensão de um modelo de melhoria de processos para este tipo específico de organizações. Este trabalho está a ser desenvolvido no âmbito do projecto de Doutoramento em Engenharia Informática.