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Antidepressant exposure reduces body size, increases fecundity and alters social behavior in the short-lived killifish Nothobranchius furzeri 全文
2020
Thoré, Eli S.J. | Philippe, Charlotte | Brendonck, Luc | Pinceel, Tom
Social and mating behavior are fundamental fitness determinants in fish. Although fish are increasingly exposed to pharmaceutical compounds that may alter expression of such behavior, potential effects are understudied. Here, we examine the impact of lifelong exposure to two concentrations (0.7 and 5.3 μg/L) of the antidepressant fluoxetine on fecundity and social behavior (i.e. sociability and male-male aggression) in the turquoise killifish, Nothobranchius furzeri. When exposed to the highest concentration of fluoxetine (5.3 μg/L), fish were smaller at maturation but they more frequently engaged in mating. In addition, in both fluoxetine treatments females roughly doubled their overall fecundity while egg fertilization rates were the same for exposed and unexposed fish. Although aggression of male fish was not impacted by fluoxetine exposure, exposed male fish (5.3 μg/L) spent more time in the proximity of a group of conspecifics, which implies an increased sociability in these individuals. Overall, the results of this study indicate that exposure to fluoxetine may result in disrupted male sociability, increased mating frequency and an increased reproductive output in fish populations.
显示更多 [+] 显示较少 [-]Assessment of O3-induced yield and economic losses for wheat in the North China Plain from 2014 to 2017, China 全文
2020
Hu, Tingjian | Liu, Shuo | Xu, Yansen | Feng, Zhaozhong | Calatayud, Vicent
Tropospheric ozone (O₃) is a pollutant of widespread concern in the world and especially in China for its negative effects on agricultural crops. For the first time, yield and economic losses of wheat between 2014 and 2017 were estimated for the North China Plain (NCP) using observational hourly O₃ data from 312 monitoring stations and exposure-response functions based on AOT40 index (accumulated hourly O₃ concentration above 40 ppb) from a Chinese study. AOT40 values from 2014 to 2017 during the wheat growing seasons (75-days, 44 before and 30 after mid-anthesis) ranged from 3.1 to 14.9 ppm h, 4.9–17.5 ppm h, 7.3–17.6 ppm h, and 0.5–18.6 ppm h, respectively. The highest AOT40 values were observed in the Beijing-Tianjin-Hebei region. The values of relative yield losses from 2014 to 2017 were in the ranges of 6.4–30.5%, 10.0–35.8%, 14.9–34.1%, and 21.6–38.2%, respectively. The total wheat production losses in NCP for 2014–2017 accounted for 18.5%, 22.7%, 26.2% and 30.8% in the whole production, while the economic losses amounted to 6,292 million USD, 8,524 million USD, 10,068 million USD, and 12,404 million USD, respectively. The important impact of O₃ in this area, which is of global importance, should be considered when assessing wheat yield production. Our results also show an increasing trend in AOT40, relative yield loss, total crop production loss and economic loss in the four consecutive years.
显示更多 [+] 显示较少 [-]Remediation of resins-contaminated soil by the combination of electrokinetic and bioremediation processes 全文
2020
Ma, Jing | Zhang, Qi | Chen, Fu | Zhu, Qianlin | Wang, Yifei | Liu, Gangjun
In this work, soil contaminated by petroleum resins was remediated by electrokinetic-bioremediation (EK-BIO) technology for 60 days. A microbial consortium, comprising Rhizobium sp., Arthrobacter globiformis, Clavibacter xyli, Curtobacterium flaccumfaciens, Bacillus subtilis, Pseudomonas aeruginosa and Bacillus sp., was used to enhance the treatment performance. The results indicate that resin removal and phytotoxicity reduction were highest in the inoculated EK process, wherein 23.6% resins was removed from the soil and wheat seed germination ratio was increased from 47% to around 90% after treatment. The microbial counts, soil basal respiration and dehydrogenase activity were positively related to resins degradation, and they could be enhanced by direct current electric field. After remediation, the C/H ratio of resins decreased from 8.03 to 6.47. Furthermore, the structure of resins was analyzed by Fourier-transform infrared spectroscopy, elemental analysis, and ¹H nuclear magnetic resonance (¹H NMR) before and after treatment. It was found that the changes of the structure of resins took place during EK-BIO treatment and finally led to the reduction of aromaticity, aromaticity condensation and phytotoxicity.
显示更多 [+] 显示较少 [-]Pre-ozonation of surface water: An effective water treatment process to reduce the risk of infection by Giardia in drinking water 全文
2020
Kondo Nakada, Liane Yuri | Urbano dos Santos, Luciana | Guimarães, José Roberto
Giardia is a protozoan parasite of primary concern for the drinking water industry. High contact times are required for Giardia inactivation by chlorination, while ozonation may be effective at much lower Ct products. In this study, we have assessed the occurrence of Giardia cysts in raw water, and in chlorinated or ozonated water from a drinking water treatment plant (DWTP) in Brazil, over a 16-month period. Moreover, we analyzed the effects of primary disinfection on cysts, and calculated the infection risk caused by the occurrence of Giardia cysts in raw water, chlorinated or ozonated water. Furthermore, we assessed the correlation of Giardia cysts with indicator bacteria in raw water. Data referring to concentration of Giardia cysts in raw water showed adherence to a gamma distribution at a significance level α = 0.05. The detection frequency and the mean concentration of Giardia cysts were higher in raw water (86.6%, 26 cysts∙L⁻¹), than in chlorinated (46.1%, 15.7 cysts·L⁻¹) or ozonated water (43.5%, 11.1 cysts·L⁻¹). Overall, Giardia non-viable cysts were detected more frequently in ozonated water (80%) than in chlorinated water (68.2%) or raw water (37.7%). Ozonation and chlorination resulted, respectively, in ≈27.5- and ≈13- fold reduction of Giardia infection risk, when compared to the risk calculated for raw water. Total coliform and Escherichia coli proved to be suitable surrogates to predict the occurrence of Giardia cysts in raw surface water, however, the indicator bacteria may not be suitable surrogates to predict the disinfection of Giardia cysts, as no correlation was found between indicator bacteria and Giardia cysts in treated water. To our knowledge, this is the first study reporting the efficacy of chlorine and ozone at Ct products actually applied at a full-scale drinking water treatment plant against Giardia cysts naturally occurring in the source water, i.e. real situation. Ozonation has proven more efficient than chlorination against Giardia cysts in surface water. Escherichia coli proved to be suitable surrogate to predict Giardia cysts in raw surface water.
显示更多 [+] 显示较少 [-]Long-term willows phytoremediation treatment of soil contaminated by fly ash polycyclic aromatic hydrocarbons from straw combustion 全文
2020
Košnář, Zdeněk | Mercl, Filip | Tlustoš, Pavel
A three-year experiment was conducted to investigate willows of Salix × smithiana Willd. (S. smithiana) phytoremediation of soil contaminated by polycyclic aromatic hydrocarbons (PAHs) derived by fly ash from biomass combustion. The total removal of ash PAHs in phytoremediation treatment was 50.9% after three consecutive years while the ash PAHs were decreased in natural attenuated soil by 9.9% in the end of the experiment. The ash and spiked PAHs with low and medium molecular weight were susceptible to be removed in higher rates than high molecular weight PAHs. Lower bioconcentration factors of individual PAHs were observed in willow shoots than in roots. The estimated relative direct removal of PAHs by S. smithiana in phytoremediation was significantly lower than 1% suggesting that the contribution of S. smithiana to take up PAHs from soil was negligible and the degradation of PAHs occurred mainly in soil. Phytoremediation using S. smithiana could be seen as a feasible and environmentally friendly approach of arable soils impacted by a PAH contaminated biomass fly ash.
显示更多 [+] 显示较少 [-]Sources and spatio-temporal distribution of aerosol polycyclic aromatic hydrocarbons throughout the Tibetan Plateau 全文
2020
Zheng, Huijun | Kang, Shichang | Chen, Pengfei | Li, Quanlian | Tripathee, Lekhendra | Maharjan, Linda | Guo, Junming | Zhang, Qianggong | Santos, Ewerton
With the recent rapid development of urbanization, atmospheric pollutants such as polycyclic aromatic hydrocarbons (PAHs) have attracted wide attention, particularly in remote regions. The Tibetan Plateau (TP), known as the third pole is adjacent to areas with heavy atmospheric pollution, such as South and East Asia. However, the spatial distribution and sources of PAHs on the TP remain unclear. Thus, we investigated the sources and spatio-temporal distributions of PAHs on the TP by combining aerosol sample data from six sites, including Ngari (NG), Laohugou (LHG), Beiluhe (BLH), Nam Co (NMC), Everest (EV), and Yulong (YL), in 2014 and 2016. The average concentrations of 15 PAHs at the six sites ranged from 3.4 to 15.2 ng m⁻³, with a decreasing trend from the marginal to inner areas of the plateau. The highest concentration was that in YL in the southeastern part of the TP, with an average of 15.2 ng m⁻³. The PAH concentrations in NG, NMC, and YL were higher in autumn and winter and lower in summer. High molecular weight PAHs usually exists in the particulate phase whereas tricyclic PAHs can change from particulate to gaseous phase, therefore it can indicate long-range transport. Tricyclic PAHs were the dominant PAHs on the TP (44%–58%), indicating long-range atmospheric transport as the major source of PAHs. Principal component analysis (PCA) and diagnostic ratio analysis showed that biomass and coal combustion were the major sources of PAHs in inland areas of the TP; however, marginal plateau areas were affected by fossil fuel emissions. Compared with levels in Beijing and other urban sites, the toxic equivalent quantity (TEQ) was low (0.36–1.06 ng m⁻³), suggesting a low risk to human and ecosystem health.
显示更多 [+] 显示较少 [-]Microbial community evolution during the aerobic biodegradation of petroleum hydrocarbons in marine sediment microcosms: Effect of biostimulation and seasonal variations 全文
2020
Hamdan, Hamdan Z. | Salam, Darine A.
Evolution of the microbial community structure in crude oil contaminated marine sediments was assessed under aerobic biodegradation during wet (18 °C) and dry (28 °C) seasons experiments, to account for seasonal variations in nutrients and temperature, under biostimulation and natural attenuation conditions. NMDS showed significant variation in the microbial communities between the wet and the dry season experiments, and between the biostimulation and the natural attenuation treatments in the dry season microcosms. No significant variation in the microbial community and oil biodegradation was observed during the wet season experiments due to high background nitrogen levels eliminating the effect of biostimulation. Larger variations were observed in the dry season experiments and were correlated to enhanced alkanes removal in the biostimulated microcosms, where Alphaproteobacteria dominated the total microbial community by the end of biodegradation (54%). Many hydrocarbonoclastic bacterial genera showed successive dominance during the operation affecting the ultimate performance of the microcosms.
显示更多 [+] 显示较少 [-]Composition characterization and biotransformation of dissolved, particulate and algae organic phosphorus in eutrophic lakes 全文
2020
Feng, Weiying | Yang, Fang | Zhang, Chen | Liu, Jing | Song, Fanhao | Chen, Haiyan | Zhu, Yuanrong | Liu, Shasha | Giesy, John P.
Characteristics and transformation of organic phosphorus in water are vital to biogeochemical cycling of phosphorus and support of blooms of phytoplankton and cyanobacteria. Using solution ³¹P nuclear magnetic resonance (NMR), combined with field surveys and lab analyses, composition and structural characteristics of dissolved phosphorus (DP), particulate phosphorus (PP) and organic P in algae were studied in two eutrophic lakes in China, Tai Lake and Chao Lake. Factors influencing migration and transformation of these constituents in lake ecosystems were also investigated. A method was developed to extract, flocculate and concentrate DP and PP from lake water samples. Results showed that orthophosphate (Ortho-P) constituted 32.4%–81.3% of DP and 43.7%–54.9% of PP, respectively; while monoester phosphorus (Mono-P) was 13.2%–54.0% of DP and 32.9%–43.7% of PP, respectively. Phosphorus in algae was mostly organic P, especially Mono-P, which was ≥50% of TP. Environmental factors and water quality parameters such as temperature (T), electrical conductivity (EC), pH, secchi depth (SD), dissolved oxygen (DO), chemical oxygen demand (CODcᵣ), chlorophyll-a (Chl-a), affected the absolute and relative concentrations of various P components in the two lakes. Increased temperature promoted bioavailable P (Ortho-P and Mono-P) release to the lake waters. The results can provide an important theoretical basis for the mutual conversion process of organic P components between various media in the lake water environment.
显示更多 [+] 显示较少 [-]Biological effects from environmental pollution by toxic metals in the “land of fires” (Italy) assessed using the biomonitor species Lunularia cruciata L. (Dum) 全文
2020
Maresca, Viviana | Sorbo, Sergio | Loppi, Stefano | Funaro, Federica | Del Prete, Davide | Basile, Adriana
The liverwort Lunularia cruciata was collected from the town of Acerra, in the heart of the so-called ‘Land of Fires’ a large area in the eastern part of Campania region of Italy affected by burning of waste and fraudulent dumping and one of the vertices of the “Italian Triangle of Death” so said for the high incidence and mortality from tumors. The data obtained from these samples were compared with samples collected in two other sites representing two different environmental conditions. The soil below the samples, and gametophytes, were collected and analyzed for the concentration of Al, As, Ba, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, V. DNA damage, Reactive Oxygen Species production and localization, activity of antioxidant enzymes and presence of chelating molecules were investigated. All biomarkers provided an answer closely related to the pollution conditions at the 3 sites. We discuss the data considering the possibility of using these biological changes as environmental pollution biomarkers. Finally, it is underlined the importance of phytochelatins due to of their specificity for metal pollution.
显示更多 [+] 显示较少 [-]China is implementing “Garbage Classification” action 全文
2020
Tong, Yeqing | Liu, Jiafa | Liu, Sizhe
In recent days, garbage classification has become a hot topic in China, and Shanghai took the lead in the implementation of garbage classification legislation in China. Starting from the current situation of garbage classification in China, this study emphasizes the garbage classification in terms of law, amount, economy, management, resourcing and successful experience of garbage classification in China, so as to provide inspiration and guidance for garbage classification for other countries.
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