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1.
Opt Express ; 31(2): 2292-2301, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36785246

RESUMEN

Several important questions in biology require non-invasive and three-dimensional imaging techniques with an appropriate spatiotemporal resolution that permits live organisms to move in an unconstrained fashion over an extended field-of-view. While selective-plane illumination microscopy (SPIM) has emerged as a powerful method to observe live biological specimens at high spatio-temporal resolution, typical implementations often necessitate constraining sample mounting or lack the required volumetric speed. Here, we report on an open-top, dual-objective oblique plane microscope (OPM) capable of observing millimeter-sized, freely moving animals at cellular resolution. We demonstrate the capabilities of our mesoscopic OPM (MesOPM) by imaging the behavioral dynamics of the sea anemone Nematostella vectensis over 1.56 × 1.56 × 0.25 mm at 1.5 × 2.8 × 5.3 µm resolution and 0.5 Hz volume rate.


Asunto(s)
Imagenología Tridimensional , Microscopía , Animales , Microscopía/métodos , Imagenología Tridimensional/métodos
2.
Sensors (Basel) ; 21(11)2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34064127

RESUMEN

Internet of Things (IoT) technologies are already playing an important role in our daily activities as we use them and rely on them to increase our abilities, connectivity, productivity and quality of life. However, there are still obstacles to achieving a unique interface able to transfer full control to users given the diversity of protocols, properties and specifications in the varied IoT ecosystem. Particularly for the case of home automation systems, there is a high degree of fragmentation that limits interoperability, increasing the complexity and costs of developments and holding back their real potential of positively impacting users. In this article, we propose implementing W3C's Web of Things Standard supported by home automation ontologies, such as SAREF and UniversAAL, to deploy the Living Lab Gateway that allows users to consume all IoT devices from a smart home, including those physically wired and using KNX® technology. This work, developed under the framework of the EC funded Plan4Act project, includes relevant features such as security, authentication and authorization provision, dynamic configuration and injection of devices, and devices abstraction and mapping into ontologies. Its deployment is explained in two scenarios to show the achieved technology's degree of integration, the code simplicity for developers and the system's scalability: one consisted of external hardware interfacing with the smart home, and the other of the injection of a new sensing device. A test was executed providing metrics that indicate that the Living Lab Gateway is competitive in terms of response performance.

3.
Chem Rev ; 117(12): 8420-8446, 2017 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-28627170

RESUMEN

The Nozaki-Hiyama-Takai-Kishi (NHTK) reaction was discovered in the late 1970s and, since then, its main application has been its use in total synthesis. In this comprehensive review, the efficiency of the NHKT reaction in the synthesis of a great number of different scaffolds present in complex natural products is analyzed. The preparation of enol and allylic and propargylic alcohol motifs is discussed, highlighting factors such as yield, chemoselectivity, stereoselectivity, or the importance of protecting groups. The review is divided into two main sections: intermolecular and intramolecular NHTK reactions. A final discussion about the current "state-of-art" and future perspectives for the use of this transformation in total synthesis is also included.


Asunto(s)
Productos Biológicos/química , Productos Biológicos/síntesis química , Técnicas de Química Sintética/métodos , Humanos
4.
Chemistry ; 22(21): 7033-5, 2016 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-26998826

RESUMEN

The terminal bromomethoxydiene (BMD) moiety of the polyhydroxylated chain present in phormidolides and oscillariolides has been synthesized for first time. Several strategies for the stereoselective synthesis of the 4-bromo-3-methoxybut-3-en-2-ones are described. Furthermore, a preliminary study to successfully introduce the BMD within the polyol chain and the fatty acid allowed us to corroborate the end structure of the polyol.


Asunto(s)
Productos Biológicos/síntesis química , Bromo/química , Butanonas/síntesis química , Macrólidos/síntesis química , Productos Biológicos/química , Butanonas/química , Halogenación , Macrólidos/química , Estereoisomerismo
5.
Chemistry ; 21(1): 150-6, 2015 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-25359690

RESUMEN

New cytotoxic polyketide macrolides named phormidolides B and C were isolated from a marine sponge of the Petrosiidae family collected off the coast of Pemba (Tanzania). The isolation, structure elucidation, and enantioselective synthesis of three diastereomers of the macrocyclic core is described herein. The described synthetic methodology started from 2-deoxy-D-ribose or 2-deoxy-L-ribose and afforded the desired macrocycles with high enantiomeric purity. The key step of the synthesis is the formation of the Z-trisubstituted double bond using a Julia-Kocienski olefination. The versatility of the synthetic methodology may provide access to other enantiopure macrocycles by making changes in the starting materials or chiral inductors.


Asunto(s)
Macrólidos/síntesis química , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Células HT29 , Humanos , Macrólidos/química , Macrólidos/toxicidad , Oxidación-Reducción , Poríferos , Estereoisomerismo
6.
Parasitol Res ; 113(9): 3185-93, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24924436

RESUMEN

The control of fasciolosis, as that of other vector-borne diseases, must be related to the control of the lymnaeid snails, the intermediate hosts of the parasite. Thus, an accurate epidemiological surveillance of the transmission foci where the infected mollusks occur is essential. For this purpose, immunoassays could be a useful tool. However, information regarding specific proteins of intramolluscan larvae and previous studies concerning monoclonal antibody generation against asexual stages of trematodes are scarce. Therefore, we explored the antigenic features of intramolluscan rediae of Fasciola hepatica to evaluate three antigenic preparations in order to use the most promising one for developing specific monoclonal antibodies. Mouse antiserum was generated against each antigen for assessing the polyclonal antibody response against the crude extract of rediae and the cross-reactivity against lymnaeids. The specific C-terminal of F. hepatica cytochrome c oxidase subunit I (first antigen), selected by in silico analyses, might not be the appropriate target for immunoassay detection of infected snails, due to its low representation in the total extract of rediae. The majoritarian mixture of low-molecular-weight proteins (<30 kDa) from the rediae homogenate (second antigen) revealed a significant cross-reactivity with lymnaeids. Evidence of the existence of mimetic immunogenic epitopes in this fraction of F. hepatica rediae was achieved. High immunogenicity of the crude extract of rediae (third antigen), mainly related to parasite's specific epitopes, was regarded. Therefore, the rediae homogenate is stated as the most promising antigen from those evaluated, for monoclonal antibody development with potentialities for detecting F. hepatica-infected snails.


Asunto(s)
Anticuerpos Antihelmínticos/inmunología , Anticuerpos Monoclonales/inmunología , Antígenos Helmínticos/inmunología , Fascioliasis/veterinaria , Animales , Epítopos , Fasciola hepatica/crecimiento & desarrollo , Fascioliasis/parasitología , Fascioliasis/prevención & control , Femenino , Ratones , Ratones Endogámicos BALB C , Modelos Moleculares , Conformación Proteica , Conejos , Caracoles/parasitología , Vacunas/inmunología
7.
Environ Sci Pollut Res Int ; 31(10): 15172-15185, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38289556

RESUMEN

Unregulated sewage discharge into the sea poses a considerable danger to marine ecosystems, with coastal regions being particularly vulnerable to this because of the impact of tourism. This issue is amplified during the summer season, as the Balearic Islands are a heavily frequented destination. This study aims to determine the water quality in five different wastewater treatment plants (WWTPs) representative on the islands. For this purpose, we analysed several parameters, including biochemical oxygen demand (BOD), chemical oxygen demand (COD), treated water flow, suspended solids (SS), nitrates (N) and phosphorus (P), at the inlet and outlet of the WWTPs for 5 years. We set particular thresholds for each parameter and documented any breach by comparing the findings with the existing regulations. The least favourable results indicate non-compliance regarding N and P levels throughout the entire study period, as well as a lack of reduction percentage. Furthermore, flow analysis reflects the significant influence of tourism on water quality, with notable increases in both population and treated water volume during the peak tourist season. Overall, the investigation offers a robust foundation for comprehending water quality in relation to coastal landscape in the Balearic Islands. It pinpoints significant worry spots and underscores tourism's immediate impact on this ecological feature.


Asunto(s)
Aguas Residuales , Purificación del Agua , España , Ecosistema , Aguas del Alcantarillado/análisis , Análisis de la Demanda Biológica de Oxígeno , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodos
8.
Sci Total Environ ; 927: 172026, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38552971

RESUMEN

Emerging pollutants (EPs) include a wide array of chemical compounds, as well as some microorganisms, which presence was unknown or unmeasurable until recently, or have recently started to be considered a threat towards the environment or animal and human health. No clear or homogeneous regulations exist for their measurement or control, and efforts should be made to assess their presence and offer solutions for their safe management, as well as to achieve an optimal protection of water resources. A previous study performed by our research group thoroughly studied a wide profile of EPs in El Hierro Island (Canary Islands) for the first time. Now, we present the study of the same panel of 70 EPs in La Palma Island (Canary Islands). 14 samples were collected in 2021, at different locations in La Palma island, representing seven municipalities (Los Llanos de Aridane, Santa Cruz de la Palma, El Paso, Breña Baja, Tazacorte, Barlovento and Fuencaliente) and four installation types (Piezometers/Wells, Wastewater Treatment Plant (WWTP), Water Gallery and Water Springs). High performance liquid chromatography-mass spectrometry (HPLC-MS) was performed to analyse the EP array, which included five chemical families: UV filters, UV blockers/stabilizers, parabens, Pharmaceutical Active Compounds (PhACs) and pesticides. Subsequently, a comprehensive descriptive and statistical analysis, including different tests was performed on the data obtained. Heterogeneous concentration levels of the EPs studied were found based on municipality and installation type among the island, with some of the PhACs and UV blockers/stabilizers showing very high levels, especially at Breña Baja and wastewater treatment plants (WWTPs). It is worth noting that some of the samples comprised within the WWTPs category were collected outside the treatment plant, after water has been treated, so they should not bear dangerous concentrations of any hazardous compound. The high presence of two pesticides, imidacloprid (ranging from 68.7 to 24,896.5 ng⋅L-1) and acetamiprid (ranging from 1010.7 to 5168.1 ng⋅L-1) was worth highlighting too. In addition, three EP concentration clusters were found to virtually divide the island based on mathematical percentiles of EP mean concentrations, which can help gain more insight into the contamination status of the island and measures that could be taken for their management. Finally, a comparison between La Palma results and the profile observed at El Hierro by our research group was presented. Altogether, the study performed calls for a need to take actions towards avoiding entrance of EPs in the water cycle, and not just focusing on remediation strategies once they have reached the groundwater, freshwater or soil.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Agua Subterránea/química , España , Plaguicidas/análisis , Islas
9.
Geohealth ; 8(6): e2024GH001067, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38884068

RESUMEN

Tourist volcanic caves are in high demand for ecotourism and geotourism lovers, as well as by sun and beach tourists as a complementary activity during their holidays. There are six tourist volcanic caves in the Canary Islands, all of them managed by the local administration of the island. The managers of these caves must ensure the safety of visitors and workers, who are exposed to natural hazards, such as radon, inherent to the environment in which the activity takes place. The methodology for analyzing natural radon radiation is based on the latest studies published by experts in this field and on previous experiences in tourist caves. This article proposes a protocol for the correct management of radon in tourist caves in the Canary Islands, adapted to current regulations, to mitigate effects on the health of visitors and workers.

10.
Sci Total Environ ; 929: 172594, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38642763

RESUMEN

Volcanic islands face unique challenges in protecting and managing their water resources due to their small size, limited freshwater availability, and vulnerability to natural hazards. The recent 2021 eruption of the Tajogaite volcano on La Palma Island in the Canary Islands, Spain, raised concerns regarding the potential impact on groundwater hydrochemistry. This work aimed to characterize and model the processes that lead to the measured hydrochemical impacts in the groundwater of La Palma as a consequence of the volcanic eruption. The study involved conducting three groundwater sampling campaigns during the eruption, and six after the eruption ceased. A total of 15 monitored points, including piezometers, wells, water galleries, and the main gully collector of the island, all relatively close (2 to15 km) to the erupted volcano, were sampled for the analysis of major solutes and SiO2. Unpublished hydrochemical data previous to the eruption were provided by the local water management authorities of La Palma (CIALP) and the Geological Survey of Spain (IGME). Statistical analyses were performed to assess the differences in groundwater composition before, during, and after the eruption, and a Principal Component Analysis (PCA) mixing model was calculated. Three compositional extreme waters were defined as end members in the system: (1) a high SiO2 computed thermal end member; (2) a low salinity computed fresh groundwater; (3) and seawater. The results of the mixing model showed two main events of maximum mixing ratios in the fresh groundwater reservoirs of La Palma after the eruption; the first one of seawater in July 2022, and the next one of thermal fluids in December 2022. This water mixing during and after the eruption, together with a volcanic CO2 input to the reservoirs, led to significant increases in the concentrations of Na, Ca, SiO2 and SO4 in fresh groundwater, as well as a drop in pH. The significance of these findings relies in improving our understanding of the effects of volcanic eruptions on groundwater, emphasizing the necessity for frequent monitoring and evaluation, given the scarcity and vulnerability of groundwater resources in volcanic islands.

11.
J Contam Hydrol ; 263: 104340, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38608419

RESUMEN

The increasing amount of plastic litter worldwide is a serious problem for the environment and its biodiversity, ecosystems, animal and human welfare and the economy. The degradation of these plastics leads to microplastics (MPs), which have been reported for the first time in groundwater in the Canary archipelago. This research investigates the presence of MPs at nine different points on La Palma and El Hierro, where samples were collected in galleries, wells and springs during the month of December 2022. Six different polymers were found with Fourier transform infrared spectroscopy (FTIR) - polypropylene (PP), polyethylene (PE), cellulose (CEL), polyethylene terephthalate (PET), polystyrene (PS) and polymethyl methacrylate (PMMA). The particle concentrations found ranged from 1 to 23 n/L, with a maximum particle size of 1900 µm, the smallest being 35 µm. PP and PE were the most common polymers found in the analysis, associated with the use of packaging, disposable products, textiles and water pipes, related to poorly maintained sewerage networks where leaks occur, allowing these MPs to escape into the environment and end up in groundwater. The detection of microplastic pollution in groundwater emphasises environmental hazards, including biodiversity disruption and water source contamination. Additionally, it presents potential risks to human health by transferring contaminants into the food chain and through respiratory exposure.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea , Microplásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Agua Subterránea/química , Agua Subterránea/análisis , Contaminantes Químicos del Agua/análisis , Islas
12.
Eval Program Plann ; 97: 102230, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36702005

RESUMEN

Identifying the effectiveness of agricultural interventions is a challenge faced by many international aid initiatives. This article reports on our efforts to document the success of agricultural aid interventions. The study is focused on evaluating cacao projects in Colombia, specifically on assessing the success of the rural Productive Partnerships Project (PAAP). The two approaches used to assess the project's success included the degree of accomplishment of four of the PAAP project's objectives and a measurement of the project performance at the local level, for which an existing performance index was utilized. Quantitative data were obtained from the project's evaluation platform developed by the PAAP project coordinators. Based on our first evaluation approach, we found that the four project objectives evaluated were not fully accomplished. While our results using the performance index provide baseline data for upcoming work assessing cacao projects' performance, the absence of precedent information constrained its interpretation. Finally, the paper offers feasible, affordable, and practical recommendations that could benefit future program planning and evaluation of international aid interventions, particularly on cacao projects worldwide.


Asunto(s)
Cacao , Humanos , Colombia , Evaluación de Programas y Proyectos de Salud , Desarrollo de Programa
13.
Ground Water ; 61(2): 255-273, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33586172

RESUMEN

Global demands for energy-efficient heating and cooling systems coupled with rising commitments toward net zero emissions is resulting in wide deployment of shallow geothermal systems, typically installed to a depth of 100 to 200 m, and in the continued growth of the global ground source heat pump (GSHP) market. Ground coupled heat pump (GCHP) systems take up to 85% of the global GSHP market. With increasing deployment of GCHP systems in urban areas coping with limited regulations, there is growing potential and risk for these systems to impact the subsurface thermal regime and to interact with each other or with nearby heat-sensitive subsurface infrastructure. In this paper, we present three numerical modeling case studies, from the UK and Canada, which examine GCHP systems' response to perturbation of the wider hydrogeological and thermal regimes. The studies demonstrate how GCHP systems can be impacted by external influences and perturbations arising from subsurface activities that change the thermal and hydraulic regimes in the area surrounding these systems. Additional subsurface heat loads near existing schemes are found to have varied impacts on system efficiency with reduction ranging from <1% to 8%, while changes in groundwater flow rates (due to a nearby groundwater abstraction) reduced the effective thermal conductivity at the study site by 13%. The findings support the argument in favor of regulation of GCHP systems or, to a minimum, their registration with records of locations and approximate heat pump capacity-even though these systems do not abstract/inject groundwater.


Asunto(s)
Agua Subterránea , Agua Subterránea/química , Monitoreo del Ambiente/métodos , Calor
14.
Sci Total Environ ; 899: 165638, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37474056

RESUMEN

Freshwater in coastal and island aquifers is a valuable resource whose availability is strongly conditioned by heterogeneity. More than 80 % of the Earth's surface is of volcanic origin, but the effect of volcanic dykes on the geometry of the saline interface that separates freshwater from seawater is still underexplored. This paper analyzes the impact of volcanic dykes on the depth of the saline interface in coastal and island aquifers and, subsequently, on the availability of fresh groundwater. Hydrogeological and hydrochemical data from a gallery, perpendicularly crossing several tens of dykes, were integrated with numerical modeling on the volcanic island of El Hierro (Canary Islands, Spain). Measured hydraulic heads demonstrated that the presence of dykes increased the hydraulic gradient by more than an order of magnitude, with respect to an adjacent area not affected by dykes. Numerical assessment confirmed that the lower the hydraulic conductivity of the dykes, the greater the depth of the saline interface inland. This impact led to fresh groundwater reserves increasing inland, relative to a hypothetical case without dykes. Numerical simulations also demonstrated that dykes can prevent salinization of production wells in coastal and island aquifers, if they are correctly located. Locating production wells far enough inland in an area affected by dykes allowed a higher freshwater extraction rate than if dykes did not exist; near the coastline, the effect tended to be the opposite. These results will be key to improving the management of fresh groundwater resources in coastal volcanic aquifers, and especially on volcanic islands such as the Hawaiian Islands or the Macaronesian archipelagos.

15.
Sci Total Environ ; 896: 165293, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37414188

RESUMEN

Contaminated groundwater is a serious problem in developed countries. The abandonment of industrial waste may lead to acid drainage affecting groundwater and severely impacting the environment and urban infrastructure. We examined the hydrogeology and hydrochemistry of an urban area in Almozara (Zaragoza, Spain); built over an old industrial zone, with pyrite roasting waste deposits, there were acid drainage problems in underground car parks. Drilling and piezometer construction, and groundwater samples revealed the existence of a perched aquifer within old sulfide mill tailings, where the building basements interrupted groundwater flow, leading to a water stagnation zone that reached extreme acidity values (pH < 2). A groundwater flow reactive transport model was developed using PHAST to reproduce flow and groundwater chemistry, in order to be used as a predictive tool for guiding remediation actions. The model reproduced the measured groundwater chemistry by simulating the kinetically controlled pyrite and portlandite dissolution. The model predicts that an extreme acidity front (pH < 2), coincident with the Fe (III) pyrite oxidation mechanism taking dominance, is propagating by 30 m/year if constant flow is assumed. The incomplete dissolution of residual pyrite (up to 18 % dissolved) predicted by the model indicates that the acid drainage is limited by the flow regime rather than sulfide availability. The installation of additional water collectors between the recharge source and the stagnation zone has been proposed, together with periodic pumping of the stagnation zone. The study findings are expected to serve as a useful background for the assessment of acid drainage in urban areas, since urbanization of old industrial land is rapidly increasing worldwide.

16.
Integr Environ Assess Manag ; 19(4): 1023-1030, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36468349

RESUMEN

Carbon dioxide emissions linked to the transport sector are particularly relevant to islands. The Canary Islands have high level of tourism, with tourists who generally travel in rented vehicles on arrival in the archipelago. In addition, mobility of the local population in the islands is also always growing. Thus, transport is one of the sectors that emits the greatest amount of greenhouse gases. In this sense, the net carbon balance becomes a pioneering study in the framework of management of high-capacity road transport routes and will help plan new strategies, which pursue the neutrality and climate resilience of the road network. It will therefore be possible to design different future scenarios, according to traffic intensities detected, to mitigate their local effects by increasing green areas, which will contribute to greater absorption. This study calculated the carbon footprint linked to vehicles on the three high-capacity roads on the island of Tenerife, as well as the carbon footprint of the public lighting attached to these roads. The absorption of carbon by vegetation planted by the Road Service and the soil located on the margins of the road have also been calculated to explore the possibility of modifying the vegetation, using other types of local shrubs and trees that have a higher absorption factor. The results demonstrate that conifers have the highest absorption factor, the Canary Island pine being the best option in this case. However, it is not always possible to place trees on the roadside, and it is necessary to resort to smaller species. This study concludes that better mobility planning, an increase in electric vehicles, improved energy production from renewable sources, and the promotion and enhancement of absorption capacity of carbon sinks are key in the face of climate change. Integr Environ Assess Manag 2023;19:1023-1030. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Asunto(s)
Gases de Efecto Invernadero , España , Gases de Efecto Invernadero/análisis , Secuestro de Carbono , Suelo , Dióxido de Carbono/análisis
17.
Ground Water ; 61(3): 375-388, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36053832

RESUMEN

Perched aquifers represent significant unexploited groundwater reserves in volcanic islands and contain valuable freshwater resources. These water reserves provide critical resources to indigenous populations suffering water scarcity. Groundwater discharged from a perched aquifer into two adjacent (14 m) springs in the volcanic summits constituted by basaltic and pyroclastic deposits of Gran Canaria Island (Spain) was examined. Based on springs discharge data, a three-dimensional groundwater flow and solute transport model of the investigated perched aquifer was calibrated to reproduce its hydraulic regime, as well as to explain the hydrochemical and isotopic composition of its main discharge systems, the studied springs. Groundwater flow simulations effectively replicated flow paths of the two springs affected by the existing geological heterogeneities, with differential travel times of 246 and 130 years, respectively, and with a convergent flow toward them partially explaining the averaged differences in electrical conductivity, δ18 O, and tritium observed between the springs. It can be concluded that, although water quality in both springs is similar and homogenous, as they come from the same aquifer system, geological heterogeneities in the upper elevation volcanic areas is likely the cause for the differences in the residence times of the two springs, which suggests that the flow regimes for the two springs are independent. The chemistry of the two springs, however, is essentially the same, with the exception of tritium, which is used to ascertain residence time.


Asunto(s)
Agua Subterránea , Agua Subterránea/química , Hidrodinámica , Islas , Tritio , Calidad del Agua , Monitoreo del Ambiente
18.
Sci Total Environ ; 872: 162204, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-36796686

RESUMEN

Emerging pollutants (EPs) are substances present in wastewater that have not been studied, previously, leading to ambiguity in regulations for their presence in water resources. Territories that are highly dependent on groundwater resources are at a high risk of suffering the consequences of EP contamination due to their dependence on good quality groundwater for agriculture, drinking, and other uses. A relevant example is El Hierro (Canary Islands), which was declared a biosphere reserve by the UNESCO in 2000 and is almost completely powered by renewable energies. Using high performance liquid chromatography-mass spectrometry, the concentrations of 70 EPs were assessed at 19 sampling points on El Hierro. The results indicated that no pesticides were present in groundwater; however, varied concentration levels of ultraviolet (UV) filters, UV stabilizers/blockers and pharmaceutically active compounds (PhACs) were found, with La Frontera being the most contaminated municipality. With regard to the different installation types, piezometers and wells were the ones showing the highest concentrations for most EPs. Interestingly, the depth of sampling correlated positively with EP concentration, and four different clusters virtually dividing the island into two areas could be identified based on the presence of each EP. More studies should be performed to ascertain why a few of the EPs showed considerably high concentrations at different depths. The results obtained highlight the need to, not only implement remediation measures once EPs have reached the soil and aquifers, but also to avoid their incorporation into the water cycle via homes, animal husbandry, agriculture, industry, and wastewater treatment plants (WWTPs).

19.
Sci Total Environ ; 837: 155789, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35561900

RESUMEN

Volcanic lakes in oceanic islands represent extremely important areas for biodiversity and offer exceptional conditions for nature-based tourism as one of the main pillars of economic growth in these regions. Nitrogen and phosphorus fertilizers are being used extensively at the Azores archipelago, similarly to other places in the world, to increase agricultural production and is causing severe pollution and eutrophication of surface freshwater reservoirs. This work concentrates on the evaluation of the efficiency of surface water diversion as a remediation measure to reduce nutrient loading and reverse eutrophication of Furnas crater lake on the island of São Miguel. Nutrient loading was monitored using an extensive water quality monitoring program in the main watershed of the eutrophicated lake that, together with watershed-scale mass balance methods and groundwater and solute transport models, allowed us to identify an average 98% efficiency in the reduction of nitrate loading. However, phosphorus total load in the discharged water to Furnas lake was observed to only be decreased by 33% due to the groundwater origin of phosphorus. Results from modelling suggested that nutrients were emitted from both point (nitrates) and diffuse (phosphorus) sources as surface runoff and as groundwater seepage, respectively. The results obtained recognized a partially successful surface water diversion, since groundwater path was not initially identified, thus highlighting the importance of groundwater flow regime in the design of such remediation measures. This work also provides a perspective on surface water diversion to revert eutrophication under a volcanic formation, where lakes can be naturally more nutrient rich.


Asunto(s)
Agua Subterránea , Lagos , Azores , China , Monitoreo del Ambiente , Eutrofización , Nitratos/análisis , Nitrógeno/análisis , Fósforo/análisis , Calidad del Agua
20.
Sustain Water Resour Manag ; 8(4): 121, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35873501

RESUMEN

The Canary Islands have a water culture tied to the exploitation of their groundwater by means of wells and water galleries. However, the growth of tourism, the increase in the local population and the development of agriculture have led to the emergence of new ways of obtaining water, such as the desalination of seawater. The presence of these desalination plants covers the entire archipelago except for the island of La Palma, and sometimes they function as a complement to water needs, while in other cases they are the only source of drinking water available. To study the environmental impact of the production of drinking water through the exploitation of the aquifer and the desalination of seawater, the carbon footprint methodology was used following the guidelines of the GHG Protocol. The result has shown that seawater installations have the largest carbon footprint, mainly due to the high electricity consumption in the islands and the electricity mix of the archipelago which, as it does not rely entirely on renewable energy sources, increases CO2 emissions into the atmosphere due to the production of drinking water in the islands.

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