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3.
Ecotoxicol Environ Saf ; 182: 109454, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31352209

RESUMO

The contamination of perfluoroalkyl substances (PFASs) in the Baiyangdian Lake has exacerbated readily since 2008. This study analyzed the perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkane sulfonic acids (PFSAs) in the surface water, sediment, and fish of the Baiyangdian Lake. In the surface water, the total concentration of PFASs ranged in 1193-3462 ng L-1 (mean 1734 ng L-1) in the rainy season and 469-1724 ng L-1 (mean 876 ng L-1) in the dry season. The total concentration of PFASs in the sediment ranged in 1.97-13.3 ng g-1 (mean 6.53 ng g-1). It was found that PFCAs and PFSAs with longer chains were more easily adsorbed in the sediment. Among the collected fish samples, the enrichment of PFASs in the tissues fell in the order of liver > cheek > muscle. For the muscle, stomach, and liver tissues of the fish samples, significant correlations existed between the δ15N values and the concentration of perfluorooctane sulfonic acid (PFOS). The contents of PFOS and perfluorooctanoic acid (PFOA) in the fish were not at a level high enough to significantly risk human health.


Assuntos
Ácidos Alcanossulfônicos/análise , Caprilatos/análise , Monitoramento Ambiental/métodos , Fluorcarbonetos/análise , Lagos/química , Poluentes Químicos da Água/análise , Animais , China , Peixes/metabolismo , Sedimentos Geológicos/química , Medição de Risco
4.
Bioresour Technol ; 290: 121748, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31323511

RESUMO

As an important technology for purifying and recycling agricultural wastewater, storing multiple-pond constructed wetlands (SMCWs) are widely used in the treatment of non-point source pollution. However, the influences of design configuration (surface area, volume, flow path, aspect ratio, water depth, percent vegetation cover and planting pattern) on pollution mitigation in SMCWs are still underexplored. To improve the sustainability of constructed wetlands, the removal performances of four groups of SMCWs were assessed through multiphasic analyses. The maximum removal efficiencies of nitrogen and phosphorus were 63.7% and 64.0%, respectively. Higher mass removal rates per square meter (MRR) and mass removal rates per cubic meter (MRRV) were observed in ecological floating treatment wetlands (EFTWs). Compared with RE, the interception performances of deep-water SMCWs were more clearly described by using MRR and MRRV. EFTWs with good plant configurations (mixed planting, 60-80% plant cover) were recommended in deep-water SMCWs (water depth > 1.5 m).


Assuntos
Purificação da Água , Áreas Alagadas , Nitrogênio , Nutrientes , Fósforo , Tanques , Águas Residuárias
5.
Chemosphere ; 234: 763-768, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31238272

RESUMO

The toxicity of polychlorinated biphenyls (PCBs) and their transformation have been intensively investigated in recent years. However, the potential mechanisms of biotransformation in a lake food web remain unclear. To explore the correlation between the PCBs and δ15N values or FAs, six fish species were collected from Dongting Lake, and various tissues were dissected to analyze the δ15N values, FAs and PCBs. Based on the wet weight (ww), the concentration of ∑PCBs115 ranged from 0.04 to 9.77 ng g-1, and the highest level was found in the gonad of Cyprinus carpio. The toxicity equivalent (TEQ) of PCBs ranged from 0.003 to 2.39 pg g-1, and the highest level was found in the fat of Silurus asotusy. The PCB levels in fish collected from Dongting Lake were at the low end of the global range. PCB28, 52, 95, 99, 101, 105 110, 118, 138, 153, 155 and 209 were found in all tissues. PCBs were distributed in a tissue-specific and species-specific manner in fish. PCB153 and 138 had a positive correlation with the TEQ in liver, gill, intestine and skin of fish on the basis of lipid weight (lw). Docosahexaenoic acid/eicosapentaenoic acid (DHA/EPA) and polyunsaturated fatty acid/saturated fatty acid (PUFA/SFA) had a positive correlation with some PCB congeners in the intestine. PCB52, ∑tetra-PCBs and Ind-PCBs had a positive correlation with the δ15N values in liver of fish on the basis of ww. PUFA/SFA and DHA/EPA might be indicators for the transfer of PCB congeners.


Assuntos
Correlação de Dados , Cadeia Alimentar , Isótopos de Nitrogênio/análise , Bifenilos Policlorados/análise , Animais , Biotransformação , Carpas/metabolismo , Ácidos Graxos , Ácidos Graxos Insaturados , Peixes , Lagos , Especificidade da Espécie , Distribuição Tecidual
6.
Water Environ Res ; 91(12): 1650-1660, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31232497

RESUMO

Recent increases in concentrations of chemical oxygen demand (COD-Cr) in Dianchi Lake, China, is an important factor affecting its water quality. Large volumes of cyanobacteria algae have also been recorded in this lake; its growth, distribution and metabolism are believed to directly or indirectly affect water quality. The relationship between metabolism of cyanobacteria and COD-Cr in Dianchi Lake, and the causes of this relationship, are examined in this study. Results show that the increase of COD-Cr concentration is closely related to the metabolism of algae, and that organic substances containing nitrogen and sugars, produced by metabolism, contribute to an increase of COD-Cr to a certain extent. The characteristics of fluorescence spectra of dissolved organic matter (DOM) in the Waihai area of Dianchi Lake are similar to those of algae culture water, and their dominant substances are protein-like substances. Algae release organic substances into water during its growth cycle and extracellular organic substances are mainly released during its normal growth and metabolism stages. Once algae cells enter the decline stage, internal organic matter is released during the dying and decomposition stages, resulting in a distinct increase of COD-Cr. A high concentration of organic matter is present in Dianchi Lake sediments, dominated by native organic matter predominantly derived from aquatic plants and plankton. This finding indicates a potential long-term risk of organic pollutants being released from dead algae cells into the lake. PRACTITIONER POINTS: There is a distinct positive correlation between COD-Cr and Chl-a concentration in Dianchi Lake. Organic substances containing nitrogen and sugars produced by algae metabolism contributed to COD-Cr. The cells die and decompose organic matter content in the water substantially increases, resulting in a distinct increase of COD-Cr. Weight >20 kDa are mainly released into the water body during the decomposition of algae cells after mortality. Organic matter content in the water substantially increases, resulting in a distinct increase of COD-Cr.


Assuntos
Cianobactérias , Lagos , Análise da Demanda Biológica de Oxigênio , China , Qualidade da Água
7.
Sci Total Environ ; 687: 128-136, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207503

RESUMO

Identification of nitrate sources and its transformations are important for the management of large lakes and reservoirs. The Three Gorges Reservoir (TGR) in China is one of the largest reservoirs around the world. In this study, stable isotopes of nitrogen (δ15N-NO3-) and oxygen (δ18O-NO3-) of nitrate in water were used to gain insights into nitrate sources and transformations in the tail area of the TGR. Bayesian mixing model has been conducted to estimate the proportional contribute of nitrate sources. The mixing modelling results indicated that NH4+ fertilizer (range 7-54%) and soil organic nitrogen (range 2-45%) were the dominant NO3--N sources in the tail area of the TGR during the three season study period. Nitrification contributed a part of NO3--N in the river water during the dry season. The nitrate from soil solution in the riparian zone with denitrified NO3- might be another major reason for the enrichment of δ15N-NO3- and δ18O-NO3- during the normal season. Reducing the use of chemical nitrogen fertilizers, especially NH4+ fertilizers, and protecting soil from erosion may be effective measures to improve water quality in the TGR.

8.
Huan Jing Ke Xue ; 40(5): 2152-2159, 2019 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087851

RESUMO

To understand the difference between transport coefficients of water runoff, sand discharge, and phosphorus flux in each subsection of a river, a judgement method for analyzing the characteristics of phosphorus transport and transformation in water of rivers was established in this study. Based on the measured data of water runoff, sand discharge, and phosphorus fraction concentrations in the water of the Three Gorges Reservoir (TGR) in January and July 2015, characteristics of phosphorus transport and transformation in the water were analyzed by using the conceptual method. The results showed that the predominant phosphorus fraction in water of the TGR was total dissolved phosphorus (TDP), which accounted for 51%-96% of total phosphorus in water. The TDP flux relative to runoff in the TGR decreased in January 2015 That was caused by the adsorption of TDP by suspended particles in the dry season. In contrast, TDP flux showed additive effect relative to water runoff in July 2015 due to exogenous water inputs with high TDP concentrations in the wet season. Both sand and total particulate phosphorus (TPP) presence in the water showed obvious sediment and retention characteristics during the two periods. The TPP flux presented an additive effect relative to sand discharge, meaning that the major transformation direction of phosphorus fractions was from TDP to TPP. The subsection between Qingxichang and Wanzhou was the main retention area of water, sand, and phosphorus in the TGR, which can be associated with the enhancement of phosphorus adsorption capacity caused by particle size reduction of suspended particles in the subsection.

9.
Environ Sci Pollut Res Int ; 26(16): 16085-16096, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30968293

RESUMO

A reliable system simulation of the reciprocal mechanism between water resource utilization and dualistic water cycle is essential to the basin water resource sustainability management. In this study, a system dynamic model was built to simulate the water cycle change and lake water environmental pressure under the influence of water resources utilization, and the procedure of a progressive operational scenario analysis of how to relieve water environment pressure was illustrated. Dianchi Lake, which is the sixth largest and the most severely polluted freshwater lake in China, was employed as a case study to demonstrate the applicability of the model. The change of runoff components and pollution load of total nitrogen from 2000 to 2030 were discussed. Also, the sustainable water resource management was ultimately realized in the planning period through three progressive levels of water resource regulation scenarios. Compared with business-as-usual scenario, the TN pollution load into lake and total water demand decrease by 27.1 and 27.3%, and the domestic water use, industry water use, tertiary industry water use, and irrigation decrease 9.0, 16.8, 29.5, and 30% in the scenario 3.


Assuntos
Conservação dos Recursos Hídricos/métodos , Modelos Teóricos , Ciclo Hidrológico , China , Lagos , Nitrogênio/análise , Desenvolvimento Sustentável , Poluição Química da Água/análise , Poluição Química da Água/prevenção & controle , Recursos Hídricos
10.
Sci Total Environ ; 671: 28-40, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30927725

RESUMO

The geochemical behavior of trace metals at the sediment/water interface in Taihu Lake, the third-largest fresh water lake in China, has been widely explored. However, information on metals in lake wetlands of the basin is lacking. Here, diffusive gradients in thin film (DGT), high-resolution dialysis technique (HR-Peeper) and traditional methods were jointly used to study the occurrence characteristics, pollution degree, bioavailability, and mobility of sediment metals in the northern lake wetlands of Jiaxing City in Taihu Lake Basin. The contents of Cr, Ni, Cu, Zn, As, Cd and Pb were 101, 52.8, 62.3, 184, 10.3, 0.4, and 39.8 mg/kg, respectively. The metals in the sediments were in an overall low enrichment level. The main form of Cd was acid-soluble (F1), and the other metals mainly existed in residual (F4) or oxidable (F3) forms. The mean DGT-labile contents (CDGT) of Cr, Ni, Cu, Zn, As, Cd and Pb were 1.3, 1.2, 9.3, 6.7, 13.4, 0.7, and 0.8 µg/L, respectively. CDGT-Cu and CDGT-As were significantly and positively related to the Cu and As contents in pore water (Csol). CDGT-Cr, CDGT-Cd, CDGT-Pb, and CDGT-Cu were significantly and positively related to CF1-Cr, CF1-Cd, CF1-Pb, and CF3-Cu, respectively. The stability of Cd was the worst with a mean risk assessment code of 40%, indicating a high risk of remobilization in the sediment. The remobilization risks of other metals were low or moderate. The CDGT/Csol ratio of Cd was also the largest, with a mean of 0.99, suggesting that the Cd resupplying ability from sediment solid to pore water was strong.

11.
Sci Total Environ ; 663: 686-695, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30731414

RESUMO

Worldwide, excessive reactive nitrogen in groundwater and surface waters is a growing problem, especially in areas that face rapid urbanization and industrialization. One example for environmental nitrogen pollution is the Lake Tai, China's third largest freshwater Lake, located in the Yangtze River basin. Due to the rapid development of the surrounding area, nitrogen compounds like nitrate are discharged into the Lake. Consequently, eutrophication and harmful algae blooms increased and led to the production of toxins directly affecting water consumers through the water supply chain. Denitrification is the main process that attenuates nitrate by converting it into atmospheric nitrogen and represents an intrinsic natural process to compensate the excess reactive nitrogen. In this study, the methodology to detect nitrate reducing bacteria on a functional gene and transcriptional level was optimized and verified in laboratory experiments with a pure culture of Pseudomonas veronii, isolated from Lake Tai. We demonstrated that transcripts analysis (mRNA) did correspond with nitrate reduction activity. Subsequently, the abundance and the activity of nitrate reducing bacteria in Lake Tai were assessed using the developed methods. We demonstrated that nitrate reducing bacteria can be found throughout all sediment and water samples taken from the northern Lake Tai in September 2017. Measurements of narG transcripts also indicated the activity of the membrane-bound nitrate reductase in the water samples. However, the bioinformatic analysis of narG sequences showed varying binding efficiency of primer and gene sites in dependence of phylogenetic groups, which may lead to an underestimation in the qPCR method. Thus, it is important to point out the precautions and limitations of primer systems to monitor nitrogen transformation by qPCR in the environment. Based on this study, mRNA detection methods are suitable for improved microbiological monitoring of denitrification, as an intrinsic process in Lake Tai to mitigate the inflowing reactive nitrogen compounds.


Assuntos
Bactérias/isolamento & purificação , Desnitrificação , Monitoramento Ambiental/métodos , Lagos/análise , Bactérias/genética , Bactérias/metabolismo , Proteínas de Bactérias/análise , China , RNA Mensageiro/análise
12.
Bioresour Technol ; 280: 295-302, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30776656

RESUMO

Storing multipond constructed wetlands, dispersed in the areas of rural lake or river basins, are unique and alternative conventional treatment systems for non-point source pollution. However, the sustainable operation and successful application of these systems remain a challenge. This study aimed to assess the seasonal variations of performance, identify operational factors of nutrients removal and fill the knowledge gap of field-scale storing multipond constructed wetlands application in a plateau lake watershed. Preferable performances for pollutant purification and operation parameters were achieved in different water seasons. Highly related to the performance of wastewater treatment, operational parameters including temperature, mass loading rate, hydraulic loading rate, hydraulic retention time and water depth were analyzed through first-order kinetics model, Spearman's rank correlation and redundancy analysis. Optimized parameters obtained through different analyzing methods revealed that appropriate hydraulic loading rate and mass loading rate would give better purification performances in wet season.


Assuntos
Lagos/química , Poluição Difusa/análise , Águas Residuárias/química , Áreas Alagadas , Estações do Ano , Poluentes Químicos da Água/análise
13.
Sci Total Environ ; 665: 774-784, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30790750

RESUMO

The concept of "carrying capacity" has been widely used in various disciplines in reference to human-environment sustainability. No unified cognition exists regarding carrying capacity limits for humans. As a typical type of carrying capacity, the water environment carrying capacity (WECC) has been researched for human-water environment sustainability. However, most recent research has focused on the assessment of the water environment carrying capacity of a certain region or river basin. The detailed resilience potential of human-water environment systems that could improve the local water environment carrying capacity has not been systematically exploited. The key concerns of the existence of water environment carrying capacity limits and the exact value have not been addressed. This study first distinguished the characteristics of related concepts, such as carrying capacity, planetary boundaries, resilience, limitations, thresholds and tipping points. An analytical framework was then established to exploit the resilience potential from the four dimensions of "scale, structure, pattern and network". The economy scale with full use of the resilience potential is 11,511,880 M yuan under the current technology and development status, which is nearly 37 times that of the current scale of the economy. The analytical framework confirms that the limit on the water environment carrying capacity is a dynamic value, which could be changed from the four dimensions. The socioeconomic scale that the local water environment can support would be nearly unlimited in some extreme ideal situation. The results would provide some enlightenment on the carrying capacity and other similar marked concepts of theoretical research and provide support for human-environment sustainability.

14.
Sci Total Environ ; 660: 32-39, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30639716

RESUMO

Although buffer zones around aquatic areas are a useful method for controlling non-point source pollution and restoring natural ecosystem services, proper delineation methods for lakes remain poorly defined, restricting their protection and the rational utilization of resources. As the width of lake buffer zones should be set to meet the area's functional targets and requirements, this study proposes a methodology for delineating these zones that includes critical source areas for non-point source pollution and ecologically sensitive areas. The proposed method was tested on Zhushan Bay, Lake Tai, China given its poor environmental condition and a renewed focus on mitigation by the local government. Data sources and relative processing methods include vector data on land use and hydrographic networks processed by ArcGIS, digital elevation model (DEM) data with 30 m resolution, soil and socioeconomic data from local governmental statistical yearbooks, NPS pollution load into lake obtained by literatures and field survey. The results showed that a minimum buffer range could be practically determined while meeting the requirements of both environmental protection and economic needs, providing a theoretical and practical basis for the improved delineation and management of lake buffer zones in watersheds dominated by non-point source pollution.

15.
Sci Total Environ ; 660: 329-339, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30640101

RESUMO

Predicting algal blooms is challenging due to rapid growth rates under suitable conditions and the complex physical, chemical, and biological processes involved. Physico-chemical parameters, monitored in this study by a high-resolution in-situ multi-sensor system and derived from lab-based water sample analyses, show the seasonal variation and have different degrees of vertical gradients across the water column. Through analyzing the changes and relations between multi-factors, we reveal pictures of water quality dynamics and algal kinetics. Nitrate has regular seasonal changes different to the seasonal patterns of total dissolved Phosphorus. Positive correlations are found between Chlorophyll a fluorescence and temperature, wind-induced resuspension and mixing promote the augment of Cyanobacteria fluorescence (Phycocyanin) signal. While the resuspension can also result in the increase of turbidity and affect the light environment for hydrophytes, the algal scums are the main reason for the high turbidity on the surface, which lower the illumination radiation in the water body. Those parameters are the primary dominants responsible for the change of algae from our monitoring data, which could be used as indicators for the dynamic changes of algae in the future.


Assuntos
Monitoramento Ambiental , Eutrofização , Lagos/análise , Microalgas/fisiologia , China , Cinética , Dinâmica Populacional , Estações do Ano , Qualidade da Água
16.
Sci Total Environ ; 658: 305-314, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30577024

RESUMO

With increasing awareness of the importance of wetlands, the number of new or restored wetlands in China is steadily growing; however, not all of them fulfill their expected ecological function. Maintaining wetlands in their optimal state is an urgent problem that requires research into the ecosystem evaluation, regulation, and biomass management of wetlands. The Ecopath with Ecosim (EWE) model, also known as the ecological channel model, is a balance model that can directly construct the ecological system structure and describe its energy flow and mass transfer through the principle of nutrition dynamics. Here, the EWE model is applied to determine the ecosystem status of a newly restored wetland, Zhushanhu wetland, in the Lake Tai buffer zone of Zhushan Bay, and evaluate the current ecological regulations and biomass control measures. Our results provide theoretical and scientific support for the management and maintenance of wetland ecological restorations.


Assuntos
Modelos Teóricos , Áreas Alagadas , Biodiversidade , China , Monitoramento Ambiental , Cadeia Alimentar
17.
Microbiologyopen ; 8(2): e00644, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29888529

RESUMO

Sediment microbial communities from plain river networks exert different effects on pollutant transformation and migration in lake basins. In this study, we examined millions of Illumina reads (16S rRNA gene amplicons) to compare lake, lake wetland, and estuary bacterial communities through a technically consistent approach. Results showed that bacterial communities in the sampled lake sediments had the highest alpha-diversity (Group B), than in sampled lake wetland sediments and estuary sediments. Proteobacteria was the most abundant (more than 30%) phyla in all the sediments. The lake sediments had more Nitrospirae (1.63%-11.75%) and Acidobacteria (3.46%-10.21%) than the lake wetland and estuary sediments, and estuary sediments had a greater abundance of the phylum Firmicutes (mean of 22.30%). Statistical analysis (LEfSe) revealed that lake wetland sediments contained greater abundances of the class Anaerolineaceae, orders Xanthomonadales, Pseudomonadales, and genera Flavobacterium, Acinetobacter. The lake sediments had a distinct community of diverse primary producers, such as phylum Acidobacteria, order Ignavibacteriales, and families Nitrospiraceae, Hydrogenophilaceae. Total phosphorus and organic matter were the main factors influencing the bacterial communities in sediments from several parts of the lake wetland and river estuary (p < .05). The novel insights into basin pollution control in plain river networks may be obtained from microbial distribution in sediments from different basin regions.


Assuntos
Bactérias/classificação , Bactérias/genética , Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Microbiota , Rios/microbiologia , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Estuários , Sequenciamento de Nucleotídeos em Larga Escala , Compostos Orgânicos/análise , Fósforo/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Água/química , Áreas Alagadas
18.
Anal Chim Acta ; 1047: 71-80, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30567666

RESUMO

In the present study, we developed a novel method to simultaneously detect eight classes of persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), polychlorinated naphthalenes (PCNs), organochlorine pesticides (OCPs), short-chain chlorinated paraffins (SCCPs) and Dechlorane Plus (DP), in sediment and fish tissue samples. The samples were extracted by accelerated solvent extraction (ASE) system, and the extracts were purified and fractionated into fraction1 and fraction2 with multi-layer silica gel column, followed by further fractionation using a basic alumina column (fraction1) and a Florisil column (fraction2), respectively. Finally, fractions were analyzed with different chromatographic columns and different detectors according to the properties of a chemical compound. The limit of detection for eight classes of POPs ranged from 1 to 30 pg/gdw in fish tissue samples, and from 1 to 33 pg/gdw in sediment samples, except for SCCPs (from 5.6 to 7.6 ng/g in fish tissue samples, and from 1.2 to 8.3 ng/gdw in sediment samples). The recoveries of eight classes of POPs spiked in fish tissue and sediment samples ranged from 43% to 120%, and from 45% to 115%, respectively. The relative standard deviation (RSD) was less than 25%. The accuracy of method was satisfactorily demonstrated by analysis of standard reference materials NIST SRM 1649b and WMF-01. In addition, the newly developed method was successfully applied for analysis of sediment and fish samples collected from the Baiyangdian Lake.


Assuntos
Dioxinas e Compostos Semelhantes a Dioxinas/análise , Músculos/química , Bifenil Polibromatos/análise , Bifenilos Policlorados/análise , Poluentes do Solo/análise , Microextração em Fase Sólida/métodos , Animais , Cromatografia Líquida , Cricetinae , Dioxinas e Compostos Semelhantes a Dioxinas/isolamento & purificação , Peixes , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos/análise , Limite de Detecção , Bifenil Polibromatos/isolamento & purificação , Bifenilos Policlorados/isolamento & purificação , Poluentes do Solo/isolamento & purificação
19.
Environ Pollut ; 241: 1018-1026, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30029309

RESUMO

Perfluorododecanoic acid (PFDoA), an artificial perfluorochemical, has been widely distributed in different ambient media and has been reported to have the potential to cause developmental neurotoxicity. However, the specific mechanism is largely unknown. In the current study, zebrafish embryos were treated with 0, 0.24, 1.2, and 6 mg/L PFDoA for 120 h. Exposure to PFDoA causes serious decreases in hatching delay, body length, as well as decreased locomotor speed in zebrafish larvae. Additionally, the acetylcholine (ACh) content as well as acetylcholinesterase (AChE) activity were determined to be significantly downregulated in PFDoA treatment groups. The level of dopamine was upregulated significantly after treating with 1.2 and 6 mg/L of PFDoA. Gene expressions related to the nervous system development were also analyzed, with the exception of the gene mesencephalic astrocyte-derived neurotrophic factor (manf), which is upregulated in the 6 mg/L treatment group. All other genes were significantly downregulated in larvae in the PFDoA group in different degrees. In general, the results demonstrated that PFDoA exposure could result in the disruption of the cholinergic system, dopaminergic signaling, and the central nervous system.


Assuntos
Ácidos Láuricos/toxicidade , Sistema Nervoso/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Animais , Regulação para Baixo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/fisiologia , Expressão Gênica , Larva/crescimento & desenvolvimento , Transdução de Sinais , Regulação para Cima , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética
20.
Appl Microbiol Biotechnol ; 102(13): 5355-5368, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29721728

RESUMO

Multiple free water surface flow constructed wetlands (multi-FWS CWs) are a variety of conventional water treatment plants for the interception of pollutants. This review encapsulated the characteristics and applications in the field of ecological non-point source water pollution control technology. The roles of in-series design and operation parameters (hydraulic residence time, hydraulic load rate, water depth and aspect ratio, composition of influent, and plant species) for performance intensification were also analyzed, which were crucial to achieve sustainable and effective contaminants removal, especially the retention of nutrient. The mechanism study of design and operation parameters for the removal of nitrogen and phosphorus was also highlighted. Conducive perspectives for further research on optimizing its design/operation parameters and advanced technologies of ecological restoration were illustrated to possibly interpret the functions of multi-FWS CWs.


Assuntos
Recuperação e Remediação Ambiental/métodos , Poluição da Água/prevenção & controle , Purificação da Água/métodos , Áreas Alagadas , Recuperação e Remediação Ambiental/instrumentação , Nitrogênio , Água/química , Purificação da Água/instrumentação
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