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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.
- Importância das plantas do sapal para reter os metais que chegam à Ria Formosa devido às atividades humanasPublication . Silva, Manuela; Duarte, D. N.; Chicharo, LuisOs sapais são ecossistemas costeiros, na transição entre a terra e o mar, que se caracterizam por ser colonizados por plantas vasculares superiores, herbáceas e arbustivas, que apresentam grande resistência à salinidade, e que por isso se designam de halófitas. Estas plantas desenvolveram ao longo do tempo estratégias de adaptação, que lhes permitem resistir a períodos de submersão, mais ou menos longos, consoante se localizam em baixo, médio ou alto sapal.
- Metals from human activities in a coastal Lagoon Saltmarsh - Sediment toxicity and phytoremediation by Sarcocornia fruticosaPublication . Silva, Manuela; Aníbal, Jaime; Duarte, D. N.; Veloso, N.; Patrício, F.; Chicharo, LuisAnthropogenic pressure on coastal areas has been increasing in the last decades, threating the saltmarshes and the ecosystem services they provide. Sarcocornia fruticosa can have an important role in sequestration of metals from human activities. This study evaluated the effect of metal toxicity in saltmarsh sediment (measured by Ecological Risk Index-ERI) on S. fruticosa ability to metal (Cd, Cr, Ni, Pb and Zn) remediation (Enrichment Factor and metal translocation). The impact of urbanization was studied through the metal loads on stormwaters during two main rainfall events, and the industrial impact was assessed through data analyses in a saltmarsh area influenced by a stream that receives industrial runoffs. The S. fruticosa response on metal remediation was affected by ERI. In more polluted locations, retained metals on roots and prevented the most toxic (Cd and Pb) from reaching the aerial organs, avoiding tissues death and metal remobilisation to the saltmarsh. Meanwhile, in rhizosediments with conditions to high metal bioavailability, S. fruticosa transported Cd and Pb to aerial organs, but used the Zn translocation to decrease their toxicity. This halophyte resilience is important to saltmarsh metal sequestration in high toxicity conditions, and allows the maintenance of other ecosystem services, contributing to the environmental protection and public health.
- Campanha de levantamento ecológico, sedimentar e hidrodinâmico da área afeta à ponte pedonal de acesso à Praia do BarrilPublication . Duarte, Duarte Nuno Ramos (Coord.); Silva, Tiago Jorge Pacheco da; Santos, João Manuel Gonçalves da Costa; Santos, Guilherme da Silva CostaO presente relatório técnico-científico foi elaborado no âmbito de uma prestação de serviços realizada pelo Centro de Investigação Marinha e Ambiental (CIMA) da Universidade do Algarve, à empresa Pedras D´El Rei-Gestão e Turismo, S.A., no âmbito do projeto de construção da nova ponte pedonal de acesso à praia do Barril.
- 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.
- Numerical analysis of the flow field and cross section design implications in a multifunctional artificial reefPublication . Maslov, Dmytro; Pereira, Eduardo; Duarte, Duarte; Miranda, Tiago; Ferreira, Vasco; Tieppo, Marcos; Cruz, Fábio; Johnson, JessicaNowadays, multifunctional artificial reefs are integrated in coastal areas all around the world. The design of such structures is currently complex and subjective. In this context, it is essential to improve overall design approaches to more effectively relate artificial reef geometry, function and optimal performance to specific deployment sites. Part of the solution to this challenge may lie in the use of in situ data to study the hydrodynamic performance of prospective artificial reefs. This research addresses this issue by performing a numerical investigation of the flow transformation of two similar artificial reef geometries, and the analysis of performance indicators based on (i) artificial reef assembly cross section, (ii) upwelling and (iii) wake regions evaluation, (iv) efficiency indices and (v) streamlines particles. Based on typical data related to wave action, a velocity inlet boundary condition was defined adopting the non-uniform velocity distribution, aimed at simulating the most realistic boundary con-dition at the chosen deployment location. The results showed that the multifunctional artificial reef assembly with the droplet shape cross section exhibited enhanced function performance when compared to a circular shape cross section by providing significantly higher values of the upwelling velocity, wake region and associated efficiency indices. In addition, the procedure presented in this study, which considers oceanographic data at the deployment site, the geometry of the artificial reef, in situ flow characteristics and boundary conditions, as well as the devised fluid flow performance indicators, can be used for the design of artificial reefs during the concept stage in an objective manner to consider the local design requirements.