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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.
- 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.
- First report of the nutritional profile and antioxidant potential of Holothuria arguinensis, a new resource for aquaculture in EuropePublication . Roggatz, Christina C.; Gonzalez-Wanguemert, Mercedes; Pereira, Hugo; Rodrigues, Maria Joao; F. G. M. Silva, Manuela; Barreira, Luísa; Varela, João; Custódio, LuísaThis work reports for the first time the nutritional profile and antioxidant potential of the edible sea cucumber Holothuria arguinensis from the North-eastern Atlantic. H. arguinensis has high levels of protein, with the amino acids profile dominated by alanine, glycine and proline and low lysine/arginine ratios. Its carbohydrate and energetic contents are also low as well as the total lipid levels, although its lipid profile is rich in polyunsaturated fatty acids (PUFA), especially arachidonic, eicosapentaenoic and docosahexaenoic acids. In addition, H. arguinensis has high levels of calcium. The water and ethanol extracts show ability to scavenge free radicals and to chelate copper and iron ions. Our results indicate that H. arguinensis has a balanced nutritional quality suitable for human consumption. In addition, it contains compounds with antioxidant potential; thus its intake can contribute for a healthy and well-balanced diet.
- Engaging young people in the development of innovative nature-inspired technologies for carbon sequestration in cities: Case studies from PortugalPublication . Moreira da Silva, Manuela; Ferreira, Lurdes; Sarmento, Teresa; Selada, CatarinaCurrently, cities are the most vulnerable places on the planet to the effects of global change, both anthropogenic and climate-related, and this is not compatible with harmony and well-being regarding the economy, nature, and future generations. Young people have a unique potential to catalyze the transformative sustainable change that the planet needs now, as they are the first generation to grow up with tangible impacts of climate change. We tested a new strategy to empower young people to foster carbon neutrality in cities by engaging them in ecosystem services quantification and technological innovation to increase CO2 sequestration in two Portuguese cities. The species with best performance for carbon sequestration were M. exelsa in Porto and O. europea in Loulé, and for air pollutant removal and hydrological regulation were P. hispanica in Porto and P. pinea in Loulé. Through the innovative advanced summer program SLI, a nature-based learning experience, young people developed two new concepts of technological solutions to accelerate city decarbonization by designing a hedge for air pollution hotspots and a biodevice to be placed at bus stops using autochthonous shrubs and mosses. Initiatives like SLI contribute to a greater awareness among young people about the drivers that brought us to the current climate emergency, motivating them towards more balanced lifestyles and creating innovative nature-based solutions towards a smart and sustainable city
- Wastewater reuse: modeling chloroform formationPublication . Rebelo, Anabela; Ferra, Isabel; Marques, Albertina; F. G. M. Silva, ManuelaThe chloroform is a substance that presents a significant risk to or via the aquatic environment. Thus, the emissions, discharges and losses of this substance need to be controlled during wastewater disinfection for reclamation and reuse purposes. Due to its carcinogenetic potential, multiple studies have been carried out on drinking and surface/natural waters but less consideration has been directed to the wastewater disinfection. The focus of this work studied the formation of chloroform during chlorination in prepared waters or artificial matrices that intended to simulate wastewaters stored in landscape ponds for green areas irrigation. The relation between reaction time, chlorine dose, and chloroform formation and the variation of the dissolved organic carbon (DOC) content during the reaction was assessed. A two-variant model was proposed to simulate breakpoint chlorination practices (when chlorine dose is equal or lower than chlorine demand) and super chlorination techniques (when chlorine dose tends to surpass chlorine demand). The model was validated by the application of actual data from working conditions of six wastewater treatment plants located in Algarve, Portugal, including other data obtained in previous research studies that were not used in the model development, and by comparing the predicted values with real measured ones.
- Reduction of carbon emissions in a mediterranean urban wastewater treatment plantPublication . Silva, Manuela; Cristovão, Luís; Marinho, Duarte; Esteves, Eduardo; Fraqueza, Gil; Martins, AntónioIn the last few decades, with the rapid growth of population, and more than half of them living in cities, the urban wastewater treatment has become a big challenge that consumes many resources, namely energy. In a climate change scenario, the Mediterranean region is facing more frequent water scarcity periods, and urban water reuse can be a solution, at least for supplying some non-potable water uses. In this context, the performance of urban wastewater treatment plants (WWTP) is of utter importance, to produce environmentally safe treated water while reducing energy consumption and carbon emissions (CE). Activated sludge is the biological process most widely used in wastewater treatment and requires aeration systems in order to promote the oxidation of organic matter and ammonia. It is known that the energy consumed in the aeration processes is of major importance for the global WWTP CE. This study was carried out in a WWTP in southern Portugal, wherein an aeration control system that responds in real time to ammonia and nitrate concentrations was tested. The system is set to optimize the duration of the aerated and non-aerated periods, for nitrification and denitrification. During the experimental period, BOD, COD, Escherichia coli, TN and TP were monitored in the treated effluent, in order to verify the quality standards that allow its reuse. The aeration control system contributed to a decrease of about 13% of the specific energy consumption, when compared with the corresponding period in previous years, representing a CE reduction of about 1.2 t CO2 eq, during the experimental period. The treated effluent maintained its high quality standards and can be used, for example, in agricultural irrigation of local crops. Aeration control systems reacting in real time can have an important role to decrease CE of urban WWTPs; however, further research is needed, including more WWTPs and analyzing seasonal variations in energy consumption over the year.
- Contributo da diretiva-quadro da água 2000/60/CE para a melhoria do controlo de qualidade da água de consumo humanoPublication . Pimentel, Cristina; Esteves, Eduardo; Moreira da Silva, ManuelaNo sentido de se analisar a evolução da qualidade da água para consumo humano imposta pelas orientações nacionais e comunitárias, em vigor nos últimos anos, procedeu-se a um estudo do desempenho dos laboratórios que realizam o seu controlo analítico. Para tal, recorreu-se à análise dos resultados de parâmetros físico-químicos dos ensaios interlaboratoriais fornecidos pela Associação Portuguesa de Laboratórios Acreditados (RELACRE), entre Maio de 2001 e Novembro de 2009, e avaliou-se a evolução temporal dos desempenhos dos laboratórios participantes, tendo por base os valores de Z-score em função da concentração do analito e o Erro normalizado aplicado à estimativa das incertezas. O Laboratório de Engenharia Sanitária da Universidade do Algarve (LES/UALG), primeiro laboratório de ensaios de águas acreditado nesta região, foi analisado como um caso de estudo. Os resultados obtidos indicam que a implementação da Diretiva-Quadro e de todas as outras orientações dela decorrentes, influenciou positivamente o desempenho dos laboratórios relativamente a nitratos, nitritos, amónia, alumínio, ferro, manganês e pH. Relativamente à avaliação da estimativa das incertezas através do Erro normalizado, também se verificou que estas melhoraram significativamente no período estudado. Para oxidabilidade, cor e turvação essa influência é menos evidente. No caso do Laboratório de Engenharia Sanitária da UALG, e no que diz respeito aos parâmetros dentro do âmbito da sua acreditação, verificou-se uma melhoria clara do seu desempenho durante o período estudado.
- A new insight into the influence of habitat on the biochemical properties of three commercial sea cucumber speciesPublication . González-Wangüemert, Mercedes; Roggatz, Christina C.; Rodrigues, Maria Joao; Barreira, Luísa; Silva, Manuela; Custódio, LuísaThis work makes a comparative evaluation of the biochemical profile of three sea commercial cucumber species (Holothuria mammata, H. polii and H. tubulosa) caught from different locations of the Mediterranean Sea (SE Spain). All species had high levels of moisture (from 73.6% in H. mammata to 81.2% in H. tubulosa), crude ash (from 9.61% in H. mammata to 14.7% in H. tubulosa) and protein (3.01% in H. tubulosa to 11.1% in H. mammata). They also had a low fat content, from 0.21% in H. tubulosa to 0.55% in H. mammata. Holothuria polii had intermediate values between the other two species, for all considered variables. All species had adequate protein/lipid ratios (H. mammata, 20:1; H. polii, 23:1; H. tubulosa, 14:1) and low lipid levels, enriched in omega-3 polyunsaturated fatty acids, especially arachidonic acid. The fatty acid profile suggests that H. polii is feeding on sediments more influenced by terrestrial inputs than the remaining species. Holothuria mammata and H. tubulosa are feeding on marine food sources mainly, but also with some terrestrial influence. The most abundant amino acids detected were alanine, arginine, glutamic acid, and glycine. All species had similar contents of essential amino acids (EAA) and ratios of EAA/non-essential amino acids. Holothuria tubulosa had a high content of toxic metals including Cr, Pb and Ni. This work highlights differences in compositional characteristics between different species of the same genus (Holothuria) from different locations.