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A review of economic calibrated mathematical programming models for agricultural water reallocation
No full textOccurrence, bioaccumulation, and ecological risk assessment of contaminants of emerging concern using native and invasive species as biomonitors
No full textTraditionally, contaminants of emerging concern (CECs) monitoring have focused on assessing their occurrence in abiotic compartments and in native fish species. The use of non-native species in environmental quality studies has recently proven to be a key tool for evaluating the CECs exposure and their ecological risks. In this study, the use of different native and invasive species was proposed to assess the environmental quality of a coastal Mediterranean wetland. A biomonitoring assessment was conducted at ten locations within the Albufera Natural Park (Spain), including irrigation channels, the lake, and the artificial wetland. The bioaccumulation of 171 CECs was evaluated in the Asian clam, the American red swamp crayfish, and the pumpkinseed sunfish, which are primary invasive species in this ecosystem. Furthermore, a comparative analysis was done with the native clam to verify whether invasive species could provide equivalent information. A total of 35 CECs were detected in at least one of the species analyzed. The Asian clam exhibited the highest number of detected compounds (23), as well as the highest chemical concentrations, particularly for pharmaceuticals. The ecological risk assessment performed with internal concentrations of CECs also pointed at the Asian clam as the most suitable species for chemical biomonitoring in this area. The compounds that had the highest contribution to the calculated ecological risk were sertraline, fluoxetine, terbuthylazine, caffeine, and oseltamivir. At most exposure sites HI values revealed high risk, indicating strong pressure from mixtures of CEs for both native and invasive species. This study shows that the analysis of chemical concentrations in invasive species can be considered a complementary tool to determine the ecological status of coastal wetlands. (c) 2025 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Assessing and Evaluating the Water Security: Water Quality, Accessibility, Availability, and Sanitation Practices Among the People of Sultanpur Village, Raozan, Chattogram
No full textAssessment of Fine (PM 2.5) Concentration from Incense Burning in the Residential Homes of Thimphu City: A Scoping Study in Bhutan
No full textConventional and biodegradable agricultural microplastics: effects on soil properties and microbial functions across a European pedoclimatic gradient
No full textAgricultural plastics like mulching films may become a major source of microplastic (MP) soil contamination during their degradation and fragmentation. This study investigates the effects of agricultural MPs from conventional (linear low-density polyethylene, PE) and biodegradable (starch-blended polybutylene adipate co-terephthalate, PBAT-BD) mulching films on soil physicochemical properties, aggregation, microbial diversity and functions, litter decomposition, and greenhouse gases emissions (GHG). For this purpose, MPs were mixed into soils at realistic MP concentrations of 0.005 % and 0.05 % (w/w) in 2022 on experimental plots in three EU countries representing different pedoclimatic conditions (Finland, Germany and Spain), followed by monitoring of the above-mentioned variables in the subsequent growing seasons 2022 and 2023. We found several significant MP-induced effects for soil properties, aggregation, microbial diversity, litter decomposition, and GHG, but the effect endpoints were less pronounced or varied considerably. Contrarily, microbial activity, contributing to soil functions such as nitrogen cycling, was consistently reduced by both conventional and biodegradable MPs. The reductions were more pronounced after the second season and for the higher MP treatment. As the higher MP concentration (i.e., 0.05 % w/w) is environmentally relevant in Europe, our findings emphasize the potential effects of environmentally relevant MP concentrations on soil health. Furthermore, the effects increased from north to south, probably modulated by varying pedoclimatic conditions, inducing reflection of a need for regionally tailored risk assessment to protect soil from plastic pollution
Efecto de contaminantes emergentes sobre la biomasa anaerobia en bioreactores de tratamiento del agua residual
No full textEl trabajo de tesis se estructura en cinco capítulos principales. En la Introducción, se contextualiza la relevancia del estudio de contaminantes emergentes en el tratamiento anaerobio de aguas residuales, vinculando los procesos de digestión anaerobia con actividades enzimáticas clave. Se ofrece además una fundamentación teórica sobre estas actividades, detallando las seleccionadas para los ensayos experimentales. En el capítulo de Metodología y materiales, se describen los materiales, diseño experimental y procedimientos empleados, así como la caracterización de parámetros convencionales (pH, densidad óptica, producción de biogás, COT) y la cuantificación de contaminantes emergentes en fases sólida y líquida. Se incluyen ensayos de toxicidad y análisis innovadores de actividades enzimáticas asociadas a la hidrólisis y al estrés oxidativo, así como evaluaciones de viabilidad celular mediante citometría de flujo y microscopía confocal. Los resultados (capítulo 3) muestran que la presencia de contaminantes emergentes inhibió la producción de biogás y la remoción de COT, sin acumulación de ácidos grasos volátiles. Los ensayos de ecotoxicidad evidenciaron mayor inhibición en los reactores expuestos a ibuprofeno y sulfametoxazol. Además, se observó diferenciación en la distribución de contaminantes entre las fases líquida y sólida. En el capítulo 4 se analizan los efectos individuales y combinados de los fármacos sobre la actividad enzimática y la viabilidad celular de la biomasa anaerobia, identificando respuestas inmediatas y diferidas según el tipo de actividad enzimática. Finalmente, en el capítulo 5 se presenta el Análisis de Componentes Principales (PCA) como herramienta estadística para reducir la dimensionalidad de los datos y facilitar la interpretación global de los resultados experimentales
Effects of environmentally relevant mixtures of microplastics on soil organisms
No full textSoil ecosystems are considered important sinks for microplastics (MPs).
However, the effects of environmentally relevant mixtures of MPs on soil
organisms have rarely been assessed. This study aimed to evaluate the chronic
effects of a mixture of MPs on two model soil organisms, the earthworm Eisenia
andrei and the springtail Folsomia candida. The MP mixture was composed of
polymers and shapes frequently found in agricultural soils amended with
sewage sludge, including HDPE and PP fragments, and PES fibres. The
organisms were exposed in LUFA 2.2 soil to MP concentrations of 0–1% dry
soil for E. andrei, and 0–5% for F. candida. This study shows that particle
ingestion by E. andrei was proportional to MP exposure levels, and the size
distribution taken up was similar to that observed in the exposure medium,
suggesting non-selective uptake behaviour. In contrast, very low ingestion
levels of MPs were found for F. candida, even at the highest test concentration.
No significant effects were found on survival, growth or reproduction of E.
andrei. However, significant adverse effects were found on the reproductive
output (number of juveniles) and juvenile dry weight for F. candida, with a
reduction of approximately 30% in both endpoints at the highest test
concentration, and calculated NOECs of 0.4% and 1%, respectively. These
adverse effects may have been caused by changes in soil properties, mobility
reduction, and/or the presence of plastic additives, instead of MP uptake. The
comparison of MP exposure concentrations in soils obtained from the literature
with the threshold concentrations derived for F. candida indicates insignificant
environmental risks at current exposure levels
Temperature‑Sensitive Lipids Reveal Intraspecific Diversity in Bacteria Isolated from an Ancient Antarctic Microbial Mat
No full textAncient Antarctic microbial mats harbour viable bacteria that have been exposed to extreme cold and arid conditions for hundreds of years. To delve into the molecular mechanisms underlaying their survival, we isolated 12 bacterial strains from a 1,000-year-old desiccated microbial mat from the McMurdo Ice Shelf and studied their lipid composition as a function of temperature. Six of the bacterial strains were classified as Paenisporosarcina macmurdoensis, and the other six as Arthrobacter sp., according to 16S rRNA gene analyses. Two strains of each taxon were incubated at their minimum and maximum growth temperatures, and the changes in their lipid profiles were analyzed. The proportion of major fatty acids (saturated, unsaturated, and iso- and anteiso-) remained relatively constant across temperature in the four strains, but the composition of hydrocarbons and alcohols differed between taxa (e.g., presence of unsaturated alkenes in Arthrobacter sp., or unidentified isoprenoid alcohols in P. macmurdoensis). This highlights the diagnostic value of non-fatty acid lipids and revealed a taxon-dependent lipid composition. Despite the taxon-associated lipid profile, incubation temperature also influenced lipid composition in both taxa, with higher temperature correlating with greater lipid richness. Interestingly, the two P. macmurdoensis strains showed distinct lipid profiles at 20°C, suggesting that intraspecific lipid diversity reflects within-species physiological variability with potential relevance for adaptation to temperature fluctuations in the mat. Therefore, assessing the influence of temperature on bacterial lipids is crucial for understanding their adaptation and survival in extreme environments, as well as for expanding species lipid inventories for biological interpretations of ancient samples
Nature’s Contributions to People (NCP) of rural freshwater ponds in Bangladesh: An exploration of the impacts of pondscape degradation
No full textNovel Strategies for Solving Environmental Problems Through Microbial Electrochemistry
No full textLas tecnologías electroquímicas microbianas (MET) han demostrado ser versátiles y muy aplicables en las ciencias ambientales. Estas tecnologías se basan en la capacidad de las bacterias electroactivas (EAB) para donar electrones a nivel extracelular. Esta capacidad permite a las EAB donar electrones a materiales electroconductores insolubles. Las primeras aplicaciones de las MET fueron generar electricidad a partir de materia orgánica pero, en las últimas décadas, se han desarrollado avances en el cambo de los biosensores, la bioelectrosíntesis, la desalinización sostenible y el tratamiento de aguas residuales (WW). La tesis actual explora como las MET pueden mejorar la capacidad de monitorear procesos biológicos, tratar WW recalcitrantes y adaptar microorganismos para aplicaciones bioelectroquímicas específicas. Esta tesis contiene material introductorio para contextualizar los 4 capítulos de investigación original, seguido de una discusión general y unas conclusiones finales. Entender los procesos metabólicos en entornos subterráneos es vital para comprender los procesos geoquímicos. Es conocido que las respiraciones microbianas en el subsuelo tienen cierta correlación con la concentración de hidrógeno producido, si bien las tasas metabólicas son difíciles de estimar. Se ha demostrado que las celdas de combustible microbianas responden a la oxidación de compuestos metabólicamente esenciales como el acetato. En el Capítulo 2, esta tesis demuestra que las celdas de combustible microbianas (MFC) pueden determinar la tasa de oxidación de acetato en sedimentos anegados. Dada la naturaleza integral del acetato como intermediario central en la fermentación anaeróbica, este biosensor MFC puede determinar las tasas metabólicas de los microoorganismos del sedimento independientemente del proceso terminal de aceptación de electrones. Durante décadas, los ingenieros de aguas ha utilizado digestores anaerobios para tratar muchos efluentes de residuos, desde aguas residuales urbanas hasta residuos de la industria alimentaria. Si bien estos sistemas pueden tratar varios corrientes de residuos y producir biogás como energía renovable, necesitan un monitoreo constante para mantener la estabilidad de los biorreactores. Los indicadores comunes sobre el estado de salud reactor requieren mucho tiempo de análisis y no resultan apropiados para proteger a los microorganismos de tóxicos presentes en los efluentes.. En el Capítulo 3, se utilizó un biosensor de celda de electrólisis microbiana (MEC) de tres electrodos para monitorear la salud de un digestor anaerobio de flujo ascendente y para detectar biocidas para proteger de posibles daños en su bioamasa. ix Los humedales construidos electroactivos, o METlands, han tratado con éxito muchos tipos de aguas residuales. Se ha demostrado que tratan aguas residuales urbanas e industriales, e incluso productos farmacéuticos recalcitrantes para otros tratamientos. El concepto METland también es en realidad un tipo de biofitro de lecho fijo. El Capítulo 4 muestra cómo un biofiltro electroactivo puede tratar un medio de aguas residuales de hidrocarburos (HC) recalcitrantes que simulan aguas residuales de refinerías de petróleo. Los biofiltros utilizan lechos aerobios y anaeróbicos alternados para seleccionar comunidades microbianas que podrían tratar de manera eficiente las aguas residuales de HC. A lo largo de los años, la investigación en METs se ha centrado fundamentalmente, en el diseño físico del reactor y en la ciencia de los materiales de los electrodos, si bien los microbioorganismos son también claves para el funcionamiento y la eficiencia de las aplicaciones bioelectroquímicas. El desarrollo de comunidades microbianas maduras que funcionen bien en dispositivos electroquímicos como las celdas de desalinización microbiana puede llevar semanas o meses. La capacidad de producir comunidades microbianas personalizadas para procesos específicos podría aumentar en gran medida el tiempo de puesta en marcha y la eficiencia. En el Capítulo 5, se combina una novedosa combinación de una celda de electroquímica microbiana de tres electrodos con un dispositivo de cultivo continuo llamado gradostato. El gradostato se utilizó para adaptar Geobacter sulfurreducens a concentraciones salinas que cambián de forma dinámica. Además, las celdas de desalinización microbianas integradas permiten el estudio de la capacidad de G. sulfurreducens para respirar un electrodo de grafito a varias salinidades y los efectos sobre las células planctónicas. La sección final de esta tesis tiene una discusión general, unas conclusiones principales y sugerencias para investigaciónes futura en el marco de la temática investigada