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Cost-effective restoration and conservation planning in Green and Blue Infrastructure designs. A case study on the Intercontinental Biosphere Reserve of the Mediterranean: Andalusia (Spain) – Morocco
No full textGreen and Blue Infrastructure (GBI) is a network designed and planned to deliver a wide range of ecosystem services and to protect biodiversity. Existing GBI designs lacked a systematic method to allocate restoration zones. This study proposes a novel approach for systematically selecting cost-effective areas for restoration on the basis of biodiversity, ecosystem services, and ecosystem condition to give an optimal spatial design of GBI. The approach was tested at a regional scale, in a transboundary setting encompassing the Intercontinental Biosphere Reserve of the Mediterranean in Andalusia (Spain) – Morocco (IBRM), across three aquatic ecosystems: freshwater, coastal and marine. We applied Marxan with Zones to stakeholder-defined scenarios of GBI in the IBRM. Specifically, we aimed to identify management zones within the GBl that addressed different conservation, restoration and exploitation objectives. Although almost all conservation targets were achieved, our results highlighted that the proportion of conservation features (i.e., biodiversity, ecosystem services) that would be compromised in the GBl, and the proportion of provisioning services that would be lost due to conservation (i.e., incidental representation) are potentially large, indicating that the probability of conflicts between conservation and exploitation goals in the area is high. The implementation of restoration zones improved connectivity across the GBI, and also achieved European and global policy targets. Our approach may help guide future applications of GBI to implement the flexible conservation management that aquatic environments require, considering many areas at different spatial scales, across multiple ecosystems, and in transboundary contexts
Electroactive biochar outperforms highly conductive carbon materials for biodegrading pollutants by enhancing microbial extracellular electron transfer
No full textThe development and full-scale application of microbial electrochemical technologies (METs) for wastewater treatment demand massive amounts of electroconductive carbon materials to promote extracellular electron transfer (EET) and biodegradation. While the potential capability of these materials and their properties to design efficient systems is still in their infancy, the state-of-the-art METs are based on highly-conductive fossil-derived carbons. In this work we evaluate the performance of different electroconductive carbon materials (graphite, coke, biochar) for supporting microbial EET and treating urban wastewater. Our results reveal that the electroconductive biochar was the most efficient biofilter-material, enabling to stimulate bioremediation at anodic potential as high as 0.6 V (maximum removal efficiency (92%) and degradation rate (185 g-COD m−3d−1)), and to fulfill the discharge limits under conditions where the other materials failed. A deep materials characterization suggests that, despite electroconductivity is necessary, the optimal EET on biochar can be mainly assigned to its large number of electroactive surface oxygen functionalities, which can reversibly exchange electrons through the geobattery mechanism. We propose the modulation of quinone-like e-acceptors by anodic polarization to promote the biodegradation capability of carbon materials. Because of its great efficiency and sustainability, electroactive biochar will greatly expand the applicability of METs at large scale
Caracterización hidrológica de la cuenca del río Coello (departamento del Tolima, Colombia) con el programa Hydro-BID
No full textDesarrollo de un modelo de balance hídrico en la cuenca alta del Río Negro (Uruguay): Análisis de la disponibilidad de agua en diferentes escenarios
No full textRecycled desalination membranes as a support material for biofilm development: A new approach for microcystin removal during water treatment
No full textIncreased harmful cyanobacterial blooms and drought are some negative impacts of global warming. To deal with cyanotoxin release during water treatment, and to manage the massive quantities of end-of-life membrane waste generated by desalination processes, we propose an innovative biological system developed from recycled reverse osmosis (RO) membranes to remove microcystins (MC). Our system, named the Recycled-Membrane Biofilm Reactor (R-MBfR), effectively removes microcystins, while reducing the pollution impact of RO membrane waste by prolonging their life span at the same time. This multidisciplinary work showed that the inherent flaw of RO membranes, i.e., fouling, can be considered an advantageous characteristic for biofilm attachment. Factors such as roughness, hydrophilic surfaces, and the role of calcium in cell-cell and cell-surface interactions, encouraged bacterial growth on discarded membranes. Biofilm development was stimulated by using a laboratory-scale membrane module simulator cell. The R-MBfR proved versatile and was capable of degrading 2 mg·L−1 of MC in 24 h. The economic feasibility of the scaling-up of the hypothetical R-MBfR was also validated. Therefore, this membrane recycling could be a future green cost-effective alternative technology for MC removal
Ecosystem-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)
Bed electrodes in microbial electrochemistry: setup, operation and characterization
No full textMicrobial electrochemical technologies have become a vital field of interest in the last two decades. Their reactors are of interest for a large community of scientists working in environmental engineering and technology, biochemistry, electrochemistry, physics, mathematical modeling, microbiology and other disciplines. Due to the fascinating fundamentals and the high promises for application at the horizon, the field is increasingly reflected in the curricula of students of the aforementioned disciplines. The main motivation for this article is to give scientists and students an overview on one specific sub-topic: bed electrodes and bed electrode reactors. After a brief introduction, these granulated electrodes are analyzed from an engineering, electrochemical and microbiological point of view. Thereby we guide the potential future operator for deciding which biotechnological processes and applications under which operational conditions (i.e. fixed-bed electrodes versus fluidized bed electrodes) may benefit by using bed electrodes. Special focus is given to the electrochemical and microbial characterization of granules. Thus we discuss a recent tool that opens the possibility to survey the electrochemical behavior of microbial biofilms on bed electrodes—the e-Clamp. Finally, two case studies of bed electrode reactors are briefly discussed
Free chlorine exposure dose (ppm·h) and its impact on RO membranes ageing and recycling potential
No full textSpiral wound thin film composite (TFC) polyamide (PA) membranes dominate the desalination market. Despite
the proven performance of reverse osmosis (RO) membranes, they are periodically replaced and usually disposed
of in landfills. The present study investigates the effect of using a diverse combination of free chlorine solutions
(from 1 to 12,240 ppm) and exposure times (from 0.5 to 6500 h) with two purposes, namely: i) to simulate
accelerated membrane ageing (low free chlorine concentration solutions) and ii) to optimize the existing re-
cycling process of end-of-life RO membranes. Membrane coupons were taken from 8′′ diameter modules (pristine
and old). Membrane permeability and rejection coefficients were obtained by filtering synthetic brackish water
(BW). Membrane surfaces were characterized by SEM and ATR-FTIR techniques. This work shows distinct PA
vulnerability depending on membrane design (brackish water (BWRO) and seawater (SWRO) reverse osmosis
membranes). Results reveal that the use of the exposure level parameter (ppm·h) as an independent basis for
comparing free chlorine exposure must be carefully employed during ageing assessments and monitoring
transition between nanofiltration (NF)-like performance to ultrafiltration (UF)-like performance. However, it can
be used consistently to convert end-of-life RO membrane into NF-like recycled membranes using concentrations
higher than 10 ppm
Recycling of end-of-life reverse osmosis membranes for membrane biofilms reactors (MBfRs). Effect of chlorination on the membrane surface and gas permeability.
No full textReducing human impacts on drinking water is one of the main challenges for the water treatment industry.
This work provides new results to support the recycling of EoL desalination reverse osmosis (RO)
membranes for Membranes Biofilm Reactors (MBfRs).We investigate if the controlled-removal of fouling
and polyamide layer may favor the use of these membranes in MBfRs. It also would allow establishing a
normalized methodology of membrane recycling, regardless of inherited fouling during its lifespan. For
this purpose, we transform by chlorination discarded brackish (BWd) and seawater (SWd) membranes
into nanofiltration (BWt-NF and SWt-NF) and ultrafiltration (BWt-UF and SWt-UF) membranes. Our
results show that chlorine attacks allow the fouling cleaning while improves the hydrophilicity and
maintains roughness only in BWt-NF. Therefore, the bacterial deposition in this membrane is greater
than the other tested membranes. Besides, the microcystin (MC) degradation capacity of BWt-NF verifies
the compatibility of the chemical modification for the biological activity of MC-degrading bacteria.
Finally, our results also provide that polyamide thin-film composite (PA-TFC) membranes, originally manufactured for salt rejection during desalination processes, offer competitive gases diffusion at low
pressures. Therefore, we conclude that the membrane recycling may provide alternative low cost and gas
permeable membranes for MBfRs, according to circular economy principles