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Implementation of biodiversity and ecosystem services in aquatic ecosystem-based management (EBM in aquatic systems)
No full textEcosystem-based management planning across aquatic realms at the Ria de Aveiro Natura 2000 territory
No full textRia de Aveiro represents a coastal territory, in which its natural capital, mostly classified under a Natura 2000 network of protected areas, is of paramount importance for the regional and national economy, supporting harbour activities and maritime traffic, agriculture, commercial fisheries, aquaculture, manufacturing, tourism, sports and recreational activities. Current and foreseen changes connected to human activities, namely land and water uses and potential conflicts, in frame of environmental policies, sustainable economic development and human well-being require the implementation of ecosystem-based management (EBM) planning processes considering the connectivity across marine, transitional, freshwater, and terrestrial domains. The main objective is to elaborate on the co-development of the EBM planning process across the three water domains, all characterized by high biodiversity and by the wide range of services provided by ecosystems and their abiotic components, for the mitigation of impacts from the management plan under implementation. The approach used follows a stepwise procedure in frame of resilience principles, considering the analysis of the relationship between the social and ecological components and on how these can be connected through risk assessment and a spatial multi-criteria analysis based on the delivery of ecosystem services. Stakeholders' perception matched the ecosystem services provisioning risk assessment and supported the planning EBM response that consist in saltmarshes and seagrasses meadows restoration programs. Compliance of the proposed measures is achievable regarding policies (policy targets and policy instruments) and feasibility (scientific and technological knowledge and financial resources). The EBM response can support the Vouga estuary management plan and regional smart specialization (RIS3 Centro)
Geobacter dominates the inner layers of a stratified biofilm on a fluidized anode during brewery wastewater treatment
No full textBioelectroventing: an electrochemical-assisted bioremediation strategy for cleaning-up atrazine-polluted soils
No full textThe absence of suitable terminal electron acceptors (TEA) in soil might limit the oxidative metabolism of environmental microbial populations. Bioelectroventing is a bioelectrochemical strategy that aims to enhance the biodegradation of a pollutant in the environment by overcoming the electron acceptor limitation and maximizing metabolic oxidation. Microbial electroremediating cells (MERCs) are devices that can perform such a bioelectroventing. We also report an overall profile of the 14 C-ATR metabolites and 14 C mass balance in response to the different treatments. The objective of this work was to use MERC principles, under different configurations, to stimulate soil bacteria to achieve the complete biodegradation of the herbicide 14 C-atrazine (ATR) to 14 CO2 in soils. Our study concludes that using electrodes at a positive potential [+600 mV (versus Ag/AgCl)] ATR mineralization was enhanced by 20-fold when compared to natural attenuation in electrode-free controls. Furthermore, ecotoxicological analysis of the soil after the bioelectroventing treatment revealed an effective clean-up in < 20 days. The impact of electrodes on soil bioremediation suggests a promising future for this emerging environmental technology
Comparison of ALD coated nanofiltration membranes to unmodified commercial membranes in mine wastewater treatment
No full textIn this study, commercial nanofiltration (NF270 and NF90, Dow Filmtec) and zinc oxide (ZnO) coated NF270 nanofiltration membranes prepared by atomic layer deposition (ALD) were applied to the purification of mine wastewaters. The characteristics of the coated nanofiltration membranes were evaluated with contact angle, roughness and zeta-potential analyses. Membrane wearing was also studied from microscopic pictures.
The waters used were purified process water and mildly contaminated wastewaters from mine sites. The target compounds were sulphate, manganese, nitrate and chloride, the removal efficiencies of which were studied. In addition, membrane fouling was under interest. It was observed that the flux recovery ratio (FRR) after the experiment was 73–85% and 83–93% with the original and the coated membranes, respectively. The relative flux was slightly increased with the coated membrane when testing the membrane efficiency with three different wastewaters. The ZnO layer on the active membrane surface reduced the reversible fouling of the NF270 membrane. Ion removal efficiencies of the coated membranes were in the same level with the uncoated membrane, i.e. removal efficiencies were high
AQUACROSS D9.2 Case Study 2 Report. The Intercontinental Biosphere Reserve of the Mediterranean: Andalusia (Spain) –Morocco. European Union’s Horizon 2020 Framework Programme for Research and Innovation Grant Agreement No. 642317. Technical Report. European Union (H2020 FP Grant Agreement)-AQUACROSS
No full textEffect of sodium hypochlorite exposure on polysulfone recycled UF membranes and their surface characterization
No full textSilica-immobilization of Geobacter sulfurreducens for constructing ready-to-use artificial bioelectrodes
No full textMicrobial electrochemical technologies (METs) rely on the control of interactions between microorganisms and electronic devices, enabling to transform chemical energy into electricity. We report a new approach to construct ready‐to‐use artificial bioelectrodes by immobilizing Geobacter sulfurreducens cells in composite materials associating silica gel and carbon felt fibres. Viability test confirmed that the majority of bacteria (ca. 70 ± 5%) survived the encapsulation process in silica and that cell density did not increase in 96 h. The double entrapment within the silica–carbon composite prevented bacterial release from the electrode but allowed a suitable mass transport (ca. 5 min after electron donor pulse), making the electrochemical characterization of the system possible. The artificial bioelectrodes were evaluated in three‐electrode reactors and the maximum current displayed was ca. 220 and 150 μA cm−3 using acetate and lactate as electron donors respectively. Cyclic voltammetry of acetate‐fed bioelectrodes revealed a sigmoidal catalytic oxidation wave, typical of more advanced‐stage biofilms. The presence of G. sulfurreducens within composites was ascertained by SEM analysis, suggesting that only part of the bacterial population was in direct contact with the carbon fibres. Preliminary analyses of the transcriptomic response of immobilized G. sulfurreducens enlightened that encapsulation mainly induces an osmotic stress to the cells. Therefore, ready‐to‐use artificial bioelectrodes represent a versatile time‐ and cost‐saving strategy for microbial electrochemical systems
Photovoltaic and photochemical hybrid system for water treatment
No full textLa falta de acceso a agua potable y electricidad es uno de los principales retos a los que se enfrenta la sociedad actual, una sociedad con al menos 1.800 millones de personas sin acceso a agua potable, ubicadas en su mayoría en zonas rurales de países en vías de desarrollo que también presentan un acceso limitado a la electricidad. A pesar de que las tecnologías convencionales para potabilizar agua son eficaces, presentan inconvenientes que limitan su utilización a nivel global, de forma que hoy en día no existe una solución óptima para desinfectar agua a bajo coste, bajo consumo energético, alta aceptación social y bajo impacto ambiental y que sea accesible a toda la población. Con el objetivo de desarrollar nuevos sistemas que ayuden a paliar esta situación, esta tesis se centró en el desarrollo y estudio de una nueva tecnología híbrida para la desinfección de agua y la generación simultánea de electricidad (SOLWAT) basada en el uso exclusivo de la radiación solar y que incrementa la eficiencia total de conversión de la energía procedente del sol utilizando cada parte del espectro para aquellos mecanismos en los que es más eficiente. Este estudio se combinó con la evaluación del sistema convencional de desinfección solar (SODIS) (utilizando botellas de plástico PET) y el estudio de la contribución de la luz UV y los componentes térmicos a la inactivación de las bacterias. Finalmente, también se incluyó un estudio sobre el estado actual de acceso al agua potable y los riesgos sanitarios asociados en los campamentos de refugiados saharauis como posible lugar para su implementación. Los resultados obtenidos confirmaron que la tecnología SOLWAT integra las funciones de desinfección solar de agua y generación de energía fotovoltaica en un único sistema que presenta mayor eficiencia de desinfección que los sistemas SODIS convencionales. Por otro lado, los resultados eléctricos mostraron que la producción eléctrica no se ve afectada por el reactor de desinfección de agua situado encima del módulo fotovoltaico, debido fundamentalmente a la menor temperatura de funcionamiento del módulo integrado en el sistema híbrido a pesar de la leve reducción de la irradiancia recibida. Además se demostró que el proceso SODIS es altamente dependiente de la temperatura del agua, indicando que las condiciones ideales de operación para el sistema SOLWAT y el tratamiento SODIS serían operar bajo altos niveles de radiación UV y temperatura ambiente o a baja temperatura ambiente combinada con altos niveles de radiación UV, siendo las peores condiciones de funcionamiento las que se corresponden con temperaturas suaves (que conllevan temperaturas de agua coincidentes con el óptimo de crecimiento de los microorganismos patógenos) y niveles de radiación UV medios o bajos. Por último, el presente estudio confirma la viabilidad de la tecnología desarrollada para contribuir a paliar la falta de acceso a agua potable y electricidad, la cual también podría ser utilizada para el tratamiento de aguas residuales de efluentes industriales y urbanos, especialmente en tratamientos terciarios mediante una tecnología ni química ni energéticamente dependiente. Por lo tanto, considerando los riesgos de contaminación microbiológica detectados en los abastecimientos de agua potable de los campamentos de refugiados saharauis y teniendo en cuenta las condiciones de irradiancia del desierto del Sáhara con altos niveles de radiación UV y temperatura ambiente, podría ser una tecnología apropiada para ser implementada a nivel doméstico y/o comunitario
