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1.
J Hazard Mater ; 421: 126712, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34388919

RESUMEN

Aquaculture is increasing at the global scale, and beneficial reuse of wastewater is becoming crucial in some regions. Here we selected a unique tertiary treatment system for study over a one-year period. This experimental ecosystem-based approach to effluent management included a treated wastewater pond (TWP), which receives 100% effluent from a wastewater treatment plant, and an aquaculture pond (AP) that receives treated water from the TWP for fish production. We examined the fate of a wide range of pharmaceutically active compounds (PhACs) in this TWP-AP system and a control pond fed by river water using traditional grab sampling and passive samplers. We then employed probabilistic approaches to examine exposure hazards. Telmisartan, carbamazepine, diclofenac and venlafaxine, exceeded ecotoxicological predicted no effect concentrations in influent wastewater to the TWP, but these water quality hazards were consistently reduced following treatment in the TWP-AP system. In addition, both grab and passive sampling approaches resulted in similar occurrence patterns of studied compounds, which highlights the potential of POCIS use for water monitoring. Based on the approach taken here, the TWP-AP system appears useful as a tertiary treatment step to reduce PhACs and decrease ecotoxicological and antibiotic resistance water quality hazards prior to beneficial reuse in aquaculture.


Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Animales , Acuicultura , Ecosistema , Monitoreo del Ambiente , Estanques , Aguas Residuales/análisis , Agua , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
2.
J Hazard Mater ; 421: 126693, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34396957

RESUMEN

Researchers interested in a paper's statement or aiming to acquire useful information from scientific papers rely heavily on references. Additionally, calculation accuracy is important for ensuring the technical soundness of scientific papers. However, inaccurate citations and calculations are common in scientific literature. A recently published paper in the Journal of Hazardous Materials reported a study on microplastics in groundwater and surface water from coastal south India (Tamil Nadu state) and the heavy metal adsorption capacities of different polymers. In this study, we identified critical calculation errors and incorrect reference citations.


Asunto(s)
Agua Subterránea , Metales Pesados , Contaminantes Químicos del Agua , Monitoreo del Ambiente , India , Microplásticos , Plásticos , Agua , Contaminantes Químicos del Agua/análisis
3.
J Hazard Mater ; 421: 126709, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34315021

RESUMEN

Nanoscale zero-valent iron nanoparticles (nZVI) have been used for groundwater remediation and wastewater treatment due to their high reactivity, high adsorption capacity and nontoxicity. However, side reactions generally occur in tandem with the target contaminants removal process, resulting in poor electron selectivity (ES) of nZVI, and subsequently restricting its commercial application. Major efforts to increase ES of nZVI have been made in recent years. This review's objective is to provide a progress report on the significant developments in nZVI's ES during the past decade. Firstly, the definition of ES and its quantification approaches were documented, and the intrinsic (i.e. particle size, crystallinity, and surface area) and extrinsic factors (i.e. solutions pH, target contaminant concentration, and presence of co-contaminants) affecting the ES of nZVI were reported. The latest techniques for increasing ES were summarized in detail, with reference made to sulfidation, magnetization, carbon loading and other features. Then the mechanisms of those strategies for ES enhancement were described. Finally, some constructive suggestions on future research directions concerning nZVI's ES in the future were proposed.


Asunto(s)
Restauración y Remediación Ambiental , Agua Subterránea , Contaminantes Químicos del Agua , Purificación del Agua , Electrones , Hierro , Contaminantes Químicos del Agua/análisis
4.
J Hazard Mater ; 421: 126688, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34315634

RESUMEN

Improper disposal of copper mining wastes can threaten the ecosystem and human health due to the high levels of potentially toxic elements released into the environment. The objective of this study was to determine the properties of Cu mining wastes generated in the eastern Amazon and their potential risks to environment and human health. Samples of forest soil and artisanal/industrial Cu mining wastes were collected and subjected to characterization of properties and pseudo-total concentrations of Al, As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, and Zn, in addition to chemical fractionation of Cu. The pH ranged from near neutrality to alkaline. Pseudo-total concentrations of Cu were high in all wastes, mainly in the artisanal rock waste, with 19,034 mg kg-1, of which 61% is concentrated in the most reactive fractions. Pollution indices indicated that the wastes are highly contaminated by Cu and moderately contaminated by Cr and Ni. However, only the artisanal rock waste is associated with environmental risk. Non-carcinogenic and carcinogenic human health risks were detected, especially from exposure to Cr in the artisanal rock waste. Prevention actions and monitoring of the artisanal mining area are necessary to avoid impacts to the local population.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Cobre/toxicidad , Ecosistema , Monitoreo del Ambiente , Humanos , Residuos Industriales/análisis , Metales Pesados/análisis , Minería , Medición de Riesgo , Contaminantes del Suelo/análisis
5.
J Hazard Mater ; 421: 126732, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34332475

RESUMEN

Bio-heavy oil (BHO) is a renewable fuel, but its efficient use is problematic because its combustion may emit hazardous air pollutants (e.g., polycyclic aromatic hydrocarbon (PAH) compounds, NOx, and SOx). Herein, catalytic fast pyrolysis over HZSM-5 zeolite was applied to upgrading BHO to drop-in fuel-range hydrocarbons with reduced contents of hazardous species such as PAH compounds and N- and S-containing species (NOx and SOx precursors). The effects of HZSM-5 desilication and linear low-density polyethylene (LLDPE) addition to the feedstock on hydrocarbon production were explored. The apparent activation energy for the thermal decomposition of BHO was up to 37.5% lowered by desilicated HZSM-5 (DeHZSM-5) compared with HZSM-5. Co-pyrolyzing LLDPE with BHO increased the content of drop-in fuel-range hydrocarbons and decreased the content of PAH compounds. The DeHZSM-5 was effective in producing drop-in fuel-range hydrocarbons from a mixture of BHO and LLDPE and suppressing the formation of N- and S-containing species and PAH compounds. The DeHZSM-5 enhanced the hydrocarbon production by up to 58.5% because of its enhanced porosity and high acid site density compared to its parent HZSM-5. This study experimentally validated that BHO can be upgraded to less hazardous fuel via catalytic fast co-pyrolysis with LLDPE over DeHZSM-5.


Asunto(s)
Contaminación del Aire , Biocombustibles , Biomasa , Catálisis , Sustancias Peligrosas , Calor
6.
J Hazard Mater ; 421: 126678, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34333410

RESUMEN

Soil contamination by arsenic (As) presents a high risk to public health, necessitating urgent remediation. This study sought to develop an efficient strategy for the phytoremediation of As-contaminated soil. The effects of Stevia rebaudiana Bertoni residue (SR) on the available As (A-As) concentration of soil and As extraction from the soil by Pteris vittata L. were studied by soil simulation, pot, and field experiments. The A-As concentration in the soil simulation experiment increased significantly by 84.20% after 20 days. The biomass, As concentration, and total extracted As of SR-treated P. vittata L. in the pot experiment increased significantly by 50.66%, 120.2%, and 171.2%, respectively, compared to the untreated control. The SR-treated rhizosphere soil in the pot experiment displayed a significant 21.72% decrease in total As concentration. In the one-year field experiment, treatment with SR resulted in a significant 191.1% increase in As extraction by P. vittata L. and a significant 10.26% reduction in rhizosphere soil As concentration compared to the control. This study proposes a potential mechanism for SR-mediated enhancement of P. vittata L. As extraction ability and provides a new, economic, and environmentally friendly method for As-contaminated soil remediation.


Asunto(s)
Arsénico , Pteris , Contaminantes del Suelo , Stevia , Arsénico/análisis , Biodegradación Ambiental , Suelo , Contaminantes del Suelo/análisis
7.
J Hazard Mater ; 421: 126750, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34339988

RESUMEN

The biological mechanisms underlying the associations between atmospheric ozone exposure and adverse cardiometabolic outcomes are yet to be identified. Imbalanced autonomic nervous system (ANS) as well as activations of the sympatho-adrenomedullary (SAM) and hypothalamic-pituitary-adrenal (HPA) axes are among possible early biological responses triggered by ozone, and may eventually lead to cardiometabolic abnormalities. To determine whether acute ozone exposure causes ANS imbalance and increases the secretion of neuroendocrine stress hormones, we conducted a randomized, double-blind, crossover trial, under controlled 2-hour exposure to either ozone (200 ppb) or clean air with intermittent exercise among 22 healthy young adults. Here we found that, compared to clean air exposure, acute ozone exposure significantly decreased the high-frequency band of heart rate variability, even after adjusting for heart rate and pre-exposure to ambient air pollutants and meteorological factors. Ozone exposure also significantly increased the serum levels of stress hormones, including corticotrophin-releasing factor, adrenocorticotropic hormone, adrenaline, and noradrenaline. Metabolomics analysis showed that acute ozone exposure led to alterations in stress hormones, systemic inflammation, oxidative stress, and energy metabolism. Our results suggest that acute ozone exposure may trigger ANS imbalance and activate the HPA and SAM axes, offering potential biological explanations for the adverse cardiometabolic effects following acute ozone exposure.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Estudios Cruzados , Frecuencia Cardíaca , Hormonas , Humanos , Ozono/toxicidad , Adulto Joven
8.
J Hazard Mater ; 421: 126708, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34352521

RESUMEN

The level and distribution of 16 USEPA Polycyclic aromatic hydrocarbon (PAHs) in aquaculture farmed fish (Mugil cephalus and Oreochromis mossambicus) and shellfish (Corbicula fluminea Formosa and Meretrix lusoria) were determined in Taiwan and then assessed cancer and non-cancer risks for those consuming these kinds of seafood. Results indicated that C. fluminea Formosa accumulated the highest average concentration of total PAHs (43.0 ± 11.3 ng/g wet weight) while M. lusoria contained the lowest concentration (20.0 ± 5.8 ng/g) among all species. The low-molecular-weight PAHs were dominant for both fish and shellfish, which consistent with other studies. Notably, parts of high-molecular-weight PAHs were found in shellfish whereas that was little in fish. The calculated hazard quotients (HQ) of all PAHs were smaller than 1 and the incremental lifetime cancer risks (ILCR) for Benzo[a]pyrene were below 1 × 10-5, suggesting that PAHs in the collected seafood could pose a low hazard to residents. Although the results indicated that the studied seafood is safe for human consumption, children and seniors post relatively higher risks, suggesting that it needs to continue monitoring and control the PAHs concentration in seafood and the associated environments.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Animales , Acuicultura , Niño , Monitoreo del Ambiente , Contaminación de Alimentos/análisis , Humanos , Hidrocarburos Policíclicos Aromáticos/análisis , Estanques , Medición de Riesgo , Alimentos Marinos/análisis , Taiwán
9.
J Hazard Mater ; 421: 126743, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34364212

RESUMEN

Limited knowledge of the combined effects of water and sediment properties and metal ionic characteristics on the solid-liquid partitioning of heavy metals constrains the effective management of urban waterways. This study investigated the synergistic influence of key water, sediment and ionic properties on the adsorption-desorption behavior of weakly-bound heavy metals. Field study results indicated that clay minerals are unlikely to adsorb heavy metals in the weakly-bound fraction of sediments (e.g., r = -0.37, kaolinite vs. Cd), whilst dissociation of metal-phosphates can increase metal solubility (e.g., r = 0.61, dissolved phosphorus vs. Zn). High salinity favors solubility of weakly-bound metals due to cation exchange (e.g., r = 0.60, conductivity vs. Cr). Dissolved organic matter does not favor metal solubility (e.g., r = -0.002, DOC vs. Pb) due to salt-induced flocculation. Laboratory study revealed that water pH and salinity dictate metal partitioning due to ionic properties of Ca2+ and H+. Selectivity for particulate phase increased in the order Cu>Pb>Ni>Zn, generally following the softness (2.89, 3.58, 2.82, 2.34, respectively) of the metal ions. Desorption followed the order Ni>Zn>Pb>Cu, which was attributed to decreased hydrolysis constant (pK1 = 9.4, 9.6, 7.8, 7.5, respectively). The study outcomes provide fundamental knowledge for understanding the mobility and potential ecotoxicological impacts of heavy metals in aquatic ecosystems.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Adsorción , China , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Agua , Contaminantes Químicos del Agua/análisis
10.
Environ Monit Assess ; 193(11): 697, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34618243

RESUMEN

Short-duration high-strength human tourism activities (SHHTA) can result in more air pollution emissions owing to increase motor vehicle usage, energy consumption and cooking fume emissions. Because of the strong uncertainty of human tourism behaviour, it is difficult to accurately assess the impact of SHHTA on air quality of natural scenic spots. To overcome this difficulty, we propose a novel ensemble empirical mode decomposition and detrended cross-correlation analysis (EEMD-DCCA) model to assess the influence of short-duration high-strength human tourism activities (SHHTA) on air quality. Zhangjiajie in China was selected as the study area. Hourly concentrations of NO2 were analysed from 1 January 2016 to 31 December 2018 at two monitoring sites, in an urban area and a scenic spot. Through EEMD, the main modes of NO2 with short-duration high-frequency were obtained for both sites. The DCCA method was used to study the cross-correlation relationship between high-frequency modes of NO2 for the urban area and scenic spot. The results show that high-frequency modes of NO2 between the two sites displayed long-range cross-correlation at the 24-h time scale. Furthermore, the quantitative impacts of meteorological factors (e.g. precipitation, temperature, and wind speed) on the DCCA exponent for high-frequency modes of NO2 at the two sites were investigated. The novel model proposed in this study is not restricted by the uncertainty of pollution emission inventory. The relationship between meteorological factors and DCCA exponents corresponds to the hypothesis that NO2 pollution of the natural scenic spot mainly came from SHHTA.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente , Humanos , Turismo
11.
Environ Monit Assess ; 193(11): 701, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34622329

RESUMEN

For the efficient functioning of a landfill, compacted bentonite is an acclaimed liner element due to its excellent adsorption capability, minimal hydraulic conductivity, and superior specific surface area (SSA). However, the leachate generation within the landfill worsens the liner material's quality, causing migration of the leachates, contaminating groundwater, and causing pollution of surrounding environment. With this perspective, a comparative assessment of the influence of real and simulated municipal solid waste (MSW) leachate on two different bentonites has been carried out in the present investigation. The two bentonites, differing precisely by their cation exchange capacity (CEC), liquid limit (LL), and swelling capability, were examined for variation in their LL, free swell (FS), and hydraulic behaviour concerning their interaction with both leachates. Results depicted that in both the leachates, LL and FS, swelling potential (SP) and pressure declined, whereas hydraulic conductivity (HC) rose. Furthermore, the bentonite quality greatly influenced the LL, FS, SP, swelling pressure, and hydraulic behaviour. Bentonite having higher CEC, SSA, and swelling ability experienced a higher variability in the LL (55.5 and 65.2% decrease), free swelling (76.9 and 83.1% decrease), SP, swelling pressure (53.3 and 56.4% decrease), and HC (13.1 and 49.4 times increase) values when permeated with simulated and real MSW leachates, respectively. The study also showed that the real MSW leachate interaction causes a higher variation in bentonite behaviour than its simulated counterpart. The study's findings would prove beneficial to design engineers for selecting bentonite types for landfill liners.


Asunto(s)
Eliminación de Residuos , Contaminantes Químicos del Agua , Bentonita , Monitoreo del Ambiente , Residuos Sólidos , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis
12.
Environ Monit Assess ; 193(11): 702, 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34622340

RESUMEN

Six plots (three as controls) were established in southern Brazil to assess the reduction in runoff by vertical mulching (vm). In the other three, ditches (0.08-m wide, 0.4-m deep) were cut perpendicular to the slope, 2-m and 12-m upslope from the bottom of the plot where a flume was installed to measure runoff. Three simulated rainfalls (80 mm h-1 for 120 min, 80 mm h-1 for 65 min, 97 mm h-1 for 65 min) were applied with a sprinkler system to generate runoff. Compared to the controls, vm delayed its beginning by 10 to 20 min and reduced its volume by 34 to 39%, because initially all and later some runoff was caught in the ditches from where it infiltrated into the surrounding soil. Based on the experimental results, we derived a method to compute the runoff reduction by vm as influenced by ditch spacing (ds), initial soil moisture content (θi), and rainfall rate and duration. Computations for a combination of four ds (5 to 20 m), five θi (16 to 32%-vol), and three rainfall regimes (124 mm h-1 for 20 min, 66 mm h-1 for 60 min, and 42 mm h-1 for 120 min) showed an increasing runoff reduction as ds or θi decreased. In some cases, runoff was even completely prevented. The reductions were larger in the 60-min than in the 20-min rainfall. For the 120-min rainfall, there was no runoff with any combination of ds and θi.


Asunto(s)
Lluvia , Movimientos del Agua , Brasil , Monitoreo del Ambiente , Suelo
13.
Environ Monit Assess ; 193(11): 699, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34622348

RESUMEN

In response to the Minamata Convention on Mercury, international organizations, governments, nonprofit organizations, and other institutions as well as individuals have worked to promote the development and implementation of safe and environmentally healthy practices, processes, and products. It is expected that the accumulation of mercury in the natural environment will decrease in volume each year. However, even after Hg ceases to be used, the Hg already accumulated in forests will continue to pose an ecological risk. Forest fires are serious events, partly because they release accumulated Hg from the environment. In this study, the effects of forest fires on the accumulation and chemical species of Hg in soil, related to the mobilization of Hg, were investigated. The research was conducted in secondary forests located near artisanal small-scale gold mining sites, where Hg is used for the amalgamation of gold in Camarines Norte, Philippines. The results showed that the original Hg accumulation level in the burned forest was not as high as that in the control forest, and that burn severity might have affected only the surface soil (0-5 cm). However, the proportion of water-soluble Hg, which was derived from ash, was increased by fire. Therefore, it is suggested that forest fires not only increase the release of Hg into the atmosphere but also increase the outflow risk to the aquatic system through rainfall.


Asunto(s)
Mercurio , Incendios Forestales , Monitoreo del Ambiente , Oro , Humanos , Mercurio/análisis , Minería , Suelo
14.
Environ Monit Assess ; 193(11): 700, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34622363

RESUMEN

Multiple companies are operating in the Salalah region of Oman but found out that no concrete practices of environmental monitoring and assessment are in place, even though industries are operating in compliance with local and international regulations. There is no baseline data available to compare for further research. Initial research was started by Sohar University in Oman for monitoring and assessment, but no conclusive outcome was discovered. The objective of this research on the Salalah LPG project is to show the way forward of creating baseline data for further study when undertaken. This research will provide the best available technique (BAT) for stiff control, environmental monitoring and assessment which can help industries to remain in compliance with local regulator EA (Environmental Authority) and international regulations IFC (International Finance Corporation) and produce with sustainability. The raw data collected from 2018 to 2020 are used in research. These data are general aspect generation from the project, dust (PM10) monitoring, noise monitoring, emissions and GHG generation from the fossil fuel (diesel) consumed on weekly and monthly basis and summarized yearly. These raw data were processed by calculation, presentation in tubular format or in curve (graph) to analyse pollutant generation. This research also gives insight into what to do if pollutants cross the regulator's parameters. Apart from regulatory compliance research paper also suggest some improvement recommendation for the betterment of company and ecosystem such as reduction in targeted total emission, GHG emission by using grid power in place of running diesel generators.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Ambientales , Ecosistema , Combustibles Fósiles , Humanos , Omán
15.
J Environ Sci (China) ; 109: 45-56, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34607673

RESUMEN

Stringent quarantine measures during the Coronavirus Disease 2019 (COVID-19) lockdown period (January 23, 2020 to March 15, 2020) have resulted in a distinct decrease in anthropogenic source emissions in North China Plain compared to the paralleled period of 2019. Particularly, 22.7% decrease in NO2 and 3.0% increase of O3 was observed in Tianjin, nonlinear relationship between O3 generation and NO2 implied that synergetic control of NOx and VOCs is needed. Deteriorating meteorological condition during the COVID-19 lockdown obscured the actual PM2.5 reduction. Fireworks transport in 2020 Spring Festival (SF) triggered regional haze pollution. PM2.5 during the COVID-19 lockdown only reduced by 5.6% in Tianjin. Here we used the dispersion coefficient to normalize the measured PM2.5 (DN-PM2.5), aiming to eliminate the adverse meteorological impact and roughly estimate the actual PM2.5 reduction, which reduced by 17.7% during the COVID-19 lockdown. In terms of PM2.5 chemical composition, significant NO3- increase was observed during the COVID-19 lockdown. However, as a tracer of atmospheric oxidation capacity, odd oxygen (Ox = NO2 + O3) was observed to reduce during the COVID-19 lockdown, whereas relative humidity (RH), specific humidity and aerosol liquid water content (ALWC) were observed with noticeable enhancement. Nitrogen oxidation rate (NOR) was observed to increase at higher specific humidity and ALWC, especially in the haze episode occurred during 2020SF, high air humidity and obvious nitrate generation was observed. Anomalously enhanced air humidity may response for the nitrate increase during the COVID-19 lockdown period.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Control de Enfermedades Transmisibles , Monitoreo del Ambiente , Humanos , Material Particulado/análisis , SARS-CoV-2
16.
Environ Monit Assess ; 193(11): 692, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34609643

RESUMEN

Understanding of flood dynamics forms the basis for the leading water resource management and flood risk mitigation practices. In particular, accurate prediction of river flow during massive flood events and capturing the hysteretic behavior of river stage-discharge are among the key interests in hydrological research. The literature demonstrates that data-driven models are significant in identifying complex and hidden relationships among dependent variables, without considering explicit physical schemes. In this regard, we aim to discover the extent to which data-driven models can recognize the hidden relationships among different hydrological variables, in order to generate accurate predictions of the river flow. A secondary aim involves the detection of whether data-driven models can digest the internal features of training inputs to extrapolate severe flood records beyond the training domain. To achieve these aims, we developed a recurrent neural network (RNN) model of two hidden layers to capture the hidden relationships among the inputs, and investigated the model's predictive capability using quantitative and qualitative analyses. The quantitative analysis comprised of a comparison between model predictions, and another set of precise independent records obtained through an advanced hydroacoustic system for reference. A qualitative approach was adopted to visualize the hysteretic behavior of the stage-discharge relations of the model records, with the high-resolution records of the hydroacoustic system. The findings display the potential of data-driven models for accurately predicting river flow. Consequently, the qualitative analysis revealed moderate correlations of stage-discharge loops as compared to the reference records. Additionally, the model was tested against severe destructive flood records generated from the East Asian monsoon and tropical cyclones. Its findings suggest that data-driven models cannot extrapolate new features beyond their training dataset. Overall, this study discusses the competence of RNNs in providing reliable and accurate river flow predictions during floods.


Asunto(s)
Monitoreo del Ambiente , Inundaciones , Hidrología , Redes Neurales de la Computación , Ríos
17.
Environ Monit Assess ; 193(11): 694, 2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34611737

RESUMEN

The Prairie Pothole Region is one of the most wetland rich areas of the world and has experienced intense disturbance from increased agricultural demands and urban sprawl. This study assessed ponds across the urban gradient for the first time in the region to determine the impacts of urbanization on water quality. Thirty ponds (ten rural, ten peri-urban, and ten urban) were randomly selected and compared based on land use type and the impervious to pervious surface ratio within 1.6 km of each pond. Water quality samples were taken monthly in 2015 and 2016, across 3 and 6 months respectively. Assessment included chemical and physical parameters, which were compared spatially across the gradient and temporally between sampling periods. Results indicate disturbance from urbanization negatively impacts water quality. Spatially across the gradient, rural pond water quality was significantly different from both peri-urban and urban ponds, whereas peri-urban and urban pond water quality was not significantly different. Temporally, differences between water quality parameters and sampling periods indicate that surrounding land use, land cover, and precipitation influence parameter concentrations across the urbanization gradient. Information from this study is useful to water professionals dealing with urban development and sprawl that continue to impact water and natural habitat.


Asunto(s)
Estanques , Calidad del Agua , Ecosistema , Monitoreo del Ambiente , Urbanización
18.
J Environ Sci (China) ; 109: 102-113, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34607659

RESUMEN

Antibiotics are widely used in humans and animals, but their transformation from surface water to groundwater and the impact of land uses on them remain unclear. In this study, 14 antibiotics were systematically surveyed in a complex agricultural area in Central China. Results indicated that the selected antibiotic concentrations in surface waters were higher in winter (average: 32.7 ng/L) than in summer (average: 17.9 ng/L), while the seasonal variation in groundwaters showed an opposite trend (2.2 ng/L in dry winter vs. 8.0 ng/L in summer). Macrolides were the predominant antibiotics in this area, with a detected frequency of over 90%. A significant correlation between surface water and groundwater antibiotics was only observed in winter (R2 = 0.58). This study further confirmed the impact of land uses on these contaminants, with optimal buffer radii of 2500 m in winter and 500 m in summer. Risk assessment indicated that clarithromycin posed high risks in this area. Overall, this study identified the spatiotemporal variability of antibiotics in a typical agricultural area in Central China and revealed the impact of land uses on antibiotic pollution in aquatic environments.


Asunto(s)
Agua Subterránea , Contaminantes Químicos del Agua , Animales , Antibacterianos/análisis , China , Monitoreo del Ambiente , Humanos , Estaciones del Año , Agua , Contaminantes Químicos del Agua/análisis
19.
J Environ Sci (China) ; 109: 15-25, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34607664

RESUMEN

Emission intensity and climate change control the transport flux and fate of persistent organic pollutants (POPs) in multiple environmental compartments. This study applied a multimedia model (BETR model) to explore alternations in the spatio-temporal trends of concentrations and transport flux of benzopyrene (BaP), phenanthrene (Phe), perfluorooctane sulfonates (PFOS) and polychlorinated biphenyls (PCBs) in the Chaohu watershed, located in the lower reaches of the Yangtze River, China in response to changes in source emissions and climate. The potential historic and future risks of these pollutants also were assessed. The results suggest that current trends in concentrations and transport were similar to that of their emissions between 2005 and 2018. During the next 100 years, temporal trends and spatial patterns were not predicted to change significantly, which is consistent with climate change. Based on sensitivity and correlation analyses, climate change had significant effects on multi-media concentrations and transport fluxes of BaP, Phe, PFOS and PCBs, and rainfall intensity was the predominant controlling factor. Risk quotients (RQs) of BaP and Phe-in soil increased from 0.42 to 0.95 and 0.06 to 0.35, respectively, from 2005 to 2090, indicating potential risks. The RQs of the other examined contaminants exhibited little potential risk in soil, water, or sediment. Based on spatial patterns, it was inferred that the ecosystem around Lake Chaohu is the most at risk. The study provides insights needed for local pollution control of POPs in the Chaohu watershed. In addition, the developed approach can be applied to other watersheds world-wide.


Asunto(s)
Cambio Climático , Contaminantes Químicos del Agua , China , Ecosistema , Monitoreo del Ambiente , Multimedia , Contaminantes Orgánicos Persistentes , Contaminantes Químicos del Agua/análisis
20.
J Environ Sci (China) ; 109: 193-205, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34607668

RESUMEN

The bioaccumulation of PAHs and metal elements in the indigenous lichens Xanthoria parietina was monitored during two years at a quarterly frequency, in 3 sites of contrasted anthropic influence. The impact of the meteorological factors (temperature, relative humidity, rainfall, wind speed) was first estimated through principal component analysis, and then by stepwise multilinear regressions to include wind directions. The pollutants levels reflected the proximity of atmospheric emissions, in particular from a large industrial harbor. High humidity and mild temperatures, and in a lower extent low wind speed and rainfall, also favored higher concentration levels. The contributions of these meteorological aspects became minor when including wind direction, especially when approaching major emission sources. The bioaccumulation integration time towards meteorological variations was on a seasonal basis (1-2 months) but the wind direction and thus local emissions also relied on a longer time scale (12 months). This showed that the contribution of meteorological conditions may be prevalent in remote places, while secondary in polluted areas, and should be definitely taken into account regarding long-term lichen biomonitoring and inter-annual comparisons. In the same time, a quadruple sampling in each site revealed a high homogeneity among supporting tree species and topography. The resulting uncertainty, including sampling, preparation and analysis was below 30% when comfortable analytical conditions were achieved. Finally, the occurrence of unexpected events such as a major forest fire, permitted to evaluate that this type of short, although intense, events did not have a strong influence on PAH and metals bioaccumulation by lichen.


Asunto(s)
Contaminantes Atmosféricos , Líquenes , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Ascomicetos , Bioacumulación , Monitoreo del Ambiente
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