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Recreational noise pollution of traditional festivals reduces the juvenile productivity of an avian urban bioindicator
2021
Bernat-Ponce, Edgar | Gil-Delgado, José A. | López-Iborra, Germán M.
Noise is a pollutant of emergent concern for ecologists and conservation biologists. Recreational noise pollution, especially unpredictable and intermittent sounds, and its effects on wildlife and biodiversity have been poorly studied. Researchers have paid very little attention to the effect of noisy traditional festivals (fireworks and powder-guns). This study aimed to explore the effect of these recreational activities on the juvenile productivity of an urban avian bioindicator: the house sparrow. We studied five pairs of localities in the Valencia Region (E Spain) with noisy traditional festivals. Each pair was composed of one locality with festivals during the breeding season and the closest similar locality, but with festivals outside the reproductive period (controls). Both locality types were sampled twice each spring (May–June of 2019 and 2020). Sampling dates were selected as 15 and 30 days after noisy festivals ended, while the control localities were sampled 1 day after the census of their correspondent town pair with noisy breeding season festivals. The ratio of the juveniles/adults detected during surveys in the influence area of festivals (100-m buffer around the parades route) was used as a house sparrow breeding success proxy. Data were analysed using GLMM: year (2019/2020), festivals season (breeding/non-breeding), survey (15/30 days), and their interactions were included as fixed factors. Pair of localities and locality nested within the pair were random factors. In 2019, juvenile productivity was lower in the towns with noisy traditional festivals during the breeding season than in the control towns. The 2020 festivals were cancelled due to COVID-19. In spring 2020, house sparrow juvenile productivity was the same in both town groups. Lockdown did not increase this species’ juvenile productivity in the control localities in 2020 versus 2019.
Afficher plus [+] Moins [-]Association of air pollution and greenness with carotid plaque: A prospective cohort study in China
2021
Xie, Yinyu | He, Weiliang | Zhang, Xiaoling | Cui, Jian | Tian, Xiaochao | Chen, Jiang | Zhang, Kaihua | Li, Shanshan | Di, Niu | Xiang, Hao | Wang, Hebo | Chen, Gongbo | Guo, Yuming
Previous studies indicated that exposure to air pollution was associated with the progress of atherosclerosis, but evidence is very limited in China and even in the world. This study aims to assess the associations of long-term exposures to air pollution and greenness with the occurrence of carotid plaque. Participants of this cohort study were urban residents and office workers who visited Hebei General Hospital for routine physical examination annually from September 2016 through to December 2018. Eligible participants were people diagnosed the absence of carotid plaque clinically at their first hospital visit and were followed up at their second or third hospital visit. Exposure to particulate matter with aerodynamic diameter less than 2.5 μm (PM₂.₅), nitrogen dioxide (NO₂) and ozone (O₃) were estimated using an inverse distance weighted (IDW) method. The level of greenness was assessed using the Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI). The associations were evaluated using Cox proportional hazards regression models. Among 4,137 participants, 575 showed the occurrence of carotid plaque during the follow-up period. After controlling for potential confounders, the hazard ratios (HRs) and 95% confidence intervals (95%CIs) of carotid plaque associated with per interquartile range (IQR) increase in PM₂.₅, NO₂, and O₃ were 1.78 (1.55, 2.03), 1.32 (1.14, 1.53) and 1.99 (1.71, 2.31), respectively. Increased EVI and NDVI were significantly associated with lower risk of carotid plaque [HR (and 95%CI): 0.84 (0.77, 0.93) and 0.87 (0.80, 0.94)]. PM₂.₅ significantly mediated 80.47% or 93.00% of the estimated association between EVI or NDVI and carotid plaque. In light of the significant associations between air pollution, greenness and carotid plaque in this study, continued efforts are needed to curb air pollution and plan more green space considering their effects on vascular disease.
Afficher plus [+] Moins [-]Impacts of bio-stimulants on pyrene degradation, prokaryotic community compositions, and functions
2021
Aḥmad, Manẓūr | Wang, Pandeng | Li, Jia-Ling | Wang, Renfei | Duan, Li | Luo, Xiaoqing | Irfan, Muhammad | Peng, Ziqi | Yin, Lingzi | Li, Wen-Jun
Bio-stimulation of the indigenous microbial community is considered as an effective strategy for the bioremediation of polluted environments. This examination explored the near effects of various bio-stimulants on pyrene degradation, prokaryotic community compositions, and functions using 16S rRNA amplicon sequencing and qPCR. At first, the results displayed significant differences (p < 0.05) between the prokaryotic community structures of the control group, PYR (contains pyrene only), and bio-stimulants amended groups. Among the bio-stimulants, biochar, oxalic acid, salicylate, NPK, and ammonium sulfate augmented the pyrene degradation potential of microbial communities. Moreover, the higher abundance of genera, such as Flavobacterium, Hydrogenophaga, Mycobacterium, Rhodococcus, Flavihumibacter, Pseudomonas, Novosphingobium, etc., across the treatments indicated that these genera play a vital role in pyrene metabolism. Based on the higher abundance of GP-RHD and nidA genes, we speculated that Gram-positive prokaryotic communities are more competent in pyrene dissipation than Gram-negative. Furthermore, the marked abundance of nifH, and pqqC genes in the NPK and SA treatments, respectively, suggested that different bio-stimulants might enrich certain bacterial assemblages. Besides, the significant distinctions (p < 0.05) between the bacterial consortia of HA (humic acid) and SA (sodium acetate) groups from NPK, OX (oxalic acid), UR (urea), NH4, and SC (salicylate) groups also suggested that different bio-stimulants might induce distinct ecological impacts influencing the succession of prokaryotic communities in distinct directions. This work provides new insight into the bacterial degradation of pyrene using the bio-stimulation technique. It suggests that it is equally important to investigate the community structure and functions along with studying their impacts on degradation when devising a bio-stimulation technology.
Afficher plus [+] Moins [-]Spatial distribution patterns and identification of microplastics on intertidal sediments from urban and semi-natural SW Atlantic estuaries
2021
Díaz-Jaramillo, Mauricio | Islas, María Soledad | González, Mariana
Although estuaries act as a sink of many pollutants, the assessment of microplastics pollution in these transition environments remain scarce or unknown. Sediments from estuarine intertidal areas possess a great ecological concern but also could act as a sink of both buoyant and non-buoyant plastic debris. In this work, we have compared microplastic abundances and their main characteristics (size, shape, colour and polymer type) on intertidal sediments from SW Atlantic Argentinean estuaries (Samborombón, Mar Chiquita, Quequén Grande and Bahía Blanca). The mean microplastics abundance in surface sediments among estuaries was ranged from 0 to 1030 ± 657 items per kg d. w. Upper intertidal areas have shown significant higher microplastic abundances in comparison with lower intertidal zones (p < 0.05). In general, higher mean abundances were observed in surface (0–10 cm) compared to deeper sediments (10–30 cm), which revealed recent deposition trends of microplastics particles. However, higher microplastic abundances were observed in deeper sediments from Bahía Blanca (p < 0.05). Large (MPs, 1–5 mm) and small microplastics (MMPs, 1–0.1 mm) were observed in sediments from all estuaries, representing from 17 to 100% of total microplastics abundance. In terms of shape, fragments and films forms were dominant in all samples while fibers and foams were moderately or poorly represented. White, black, blue and transparent particles were observed as the main colour contribution of microplastics in sediments. The most common polymers identified included polyethylene, polyethylene terephthalate/polyester, polyvinyl chloride and polypropylene. The results showed that microplastic characteristics are different among the estuarine environments, which suggests different anthropogenic sources. Besides, deeper sediments should also be included on intertidal sediment monitoring to identify potential environmental liabilities from anthropogenically impacted estuaries.
Afficher plus [+] Moins [-]Stabilization of acid-rich bio-oil by catalytic mild hydrotreating
2021
Choi, Wonjun | Jo, Hyeonmin | Choi, Jae-Wook | Suh, Dong Jin | Lee, Hyunjoo | Kim, Changsoo | Kim, Kwang-ho | Lee, Kwan Young | Ha, Jeong-Myeong
Although liquid products derived from the pyrolysis of biomass are promising for the production of petroleum-like hydrocarbon fuels, the catalytic burden of hydrodeoxygenation must be reduced to achieve feasible upgrading processes. Herein, mild hydrotreating of an acid-rich biomass pyrolysis oil (bio-oil) with an unusually high total acid number (588 mg KOH/g bio-oil) was performed to stabilize the low-quality bio-oil. Ru-added TiO₂-supported transition metal catalysts stabilized the bio-oil by reducing its acidity more compared to what could be achieved by Ru-free catalysts; this process also leads to lower loss of organic compounds compared to when using a Ru/TiO₂ catalyst. Based on the performance of transition metal catalysts, including Ni, Co, and Cu, supported on TiO₂, tungstate-zirconia, or SiO₂, supported bimetallic catalysts were prepared by adding Ru to the TiO₂-supported metal catalysts. The bimetallic catalysts Ru/Ni/TiO₂ and Ru/Co/TiO₂ exhibited good decarboxylation activity for the removal of carboxylic acids and a higher yield of organic compounds compared to that provided by Ru, which can be deemed appropriate for feedstocks when hydrodeoxygenation needs to suppress the loss of organic reactants. Using these catalysts, the carboxylic acid concentration was reduced to 319–323 mg KOH/g bio-oil with organic yields of 62–63 wt% at reaction temperatures 150–170 °C lower than the temperature required for direct conversion of carboxylic acids to alcohols or deoxygenates. The improved catalytic hydrotreating activity of Ru-added transition metals can be attributed to the high acid site densities of these catalysts along with their improved hydrogenation activities.
Afficher plus [+] Moins [-]Seasonal variation in the effects of artificial light at night on the occurrence of nocturnally migrating birds in urban areas
2021
La Sorte, Frank A. | Horton, Kyle G.
Urban areas often contain large numbers of migratory bird species during seasonal migration, many of which are nocturnal migrants. How artificial light at night (ALAN) and urban landcover are associated with the diurnal occurrence of nocturnal migrants within urban areas across seasons has not been explored. Here, we use eBird bird occurrence information to estimate the seasonal species richness of nocturnally migrating passerines (NMP) within 333 well surveyed urban areas within the contiguous USA. We model the relationship between seasonal NMP species richness and ALAN, proportion of tree canopy cover, and proportion of impervious surface. NMP species richness reached its highest levels during spring and autumn migration and lowest during the winter and summer. Greater tree canopy cover was associated with higher NMP species richness during spring and autumn migration and the summer. A 10% increase in the proportion of tree canopy cover was associated with a 2.0% increase in NMP species richness during spring migration, a 1.8% increase during autumn migration, and a 0.9% increase during the summer. More impervious surface was associated with higher NMP species richness during the winter. A 10% increase in the proportion of impervious surface was associated with a 6.1–9.8% increase in NMP species richness. Higher ALAN was associated with lower NMP species richness during the winter and summer, and higher NMP species richness during spring and autumn migration. A 50% increase in ALAN was associated with a 3.0–3.6% decrease in NMP species richness during the winter, a 1.7% increase during spring migration, a 2.1% decrease during the summer, and a 5.0% increase during autumn migration. These findings highlight the variable effects of ALAN and urban landcover on the seasonal occurrence of NMP species in urban areas, the value of tree canopy cover during migration and the breeding season, and the importance of reducing ALAN during migration.
Afficher plus [+] Moins [-]Metabolic, immunologic, and histopathologic responses on premetamorphic American bullfrog (Lithobates catesbeianus) following exposure to lithium and selenium
2021
Pinto-Vidal, Felipe Augusto | Carvalho, Cleoni dos Santos | Abdalla, Fábio Camargo | Ceschi-Bertoli, Letícia | Moraes Utsunomiya, Heidi Samantha | Henrique da Silva, Renan | Salla, Raquel Fernanda | Jones-Costa, Monica
The presence of chemicals and the destruction of freshwater habitats have been addressed as one of the reasons for the decline in the amphibians’ populations worldwide. Considering the threat that these animals have been suffering in tropical regions, the present study tested if the Brazilian legislation, concerning the permissive levels of lithium and selenium in water bodies and effluents, warrants the protection of aquatic life. To do so, we assessed the metabolic, immunologic, and histopathologic alterations in liver samples of American bullfrog (Lithobates catesbeianus), at the premetamorphic stage, through biomarkers indicative of general energetic status, i.e., glucose, lipid, and protein metabolism using biochemical and histochemical approaches. The immunologic responses were assessed by the quantification of melanomacrophage centres (MMCs); the histopathologic evaluation of the liver sections was also performed. The assay was carried out over 21 days with two periods of sampling (after 7 and 21 days) to assess the effects of exposure over time. The animals were exposed to the considered safe levels of lithium (2.5 mg L⁻¹) and selenium (10 μg L⁻¹), both, isolated and mixed. The exposed animals showed alterations in glucose and lipid metabolism throughout the experiment. The intense presence of MMCs and histopathological responses are compatible with hepatotoxicity. The toxicity expressed by the employed animal model indicates that the Brazilian environmental legislation for the protection of aquatic life needs to be updated. With this study, we intend to provide data for better environmental policies and bring attention to sublethal effects triggered by the presence of contaminants in the aquatic environment.
Afficher plus [+] Moins [-]Earthworm and arbuscular mycorrhiza interactions: Strategies to motivate antioxidant responses and improve soil functionality
2021
Wang, Gen | Wang, Li | Ma, Fang | Yang, Dongguang | You, Yongqiang
Earthworms and arbuscular mycorrhizal fungi (AMF) act synergistically in the rhizosphere and may increase host plant tolerance to Cd. However, mechanisms by which earthworm-AMF-plant partnerships counteract Cd phytotoxicity are unknown. Thus, we evaluated individual and interactive effects of these soil organisms on photosynthesis, antioxidant capacity, and essential nutrient uptake by Solanum nigrum, as well as on soil quality following Cd exposure (0–120 mg kg⁻¹). Decreases in biomass and photosynthetic activity, as well as nutrient imbalances were observed in Cd-stressed plants; however, the addition of AMF and earthworms reversed these effects. Cd exposure increased superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, whereas inoculation with Rhizophagus intraradices decreased those. Soil enzymatic activity decreased by 15–60% with increasing Cd concentrations. However, Cd-mediated toxicity was partially reversed by soil organisms. Earthworms and AMF ameliorated soil quality based on soil enzyme activity. At 120 mg kg⁻¹ Cd, the urease, catalase, and acid phosphatase activities were 1.6-, 1.4-, and 1.2-fold higher, respectively, in soils co-incubated with earthworms and AMF than in uninoculated soil. Cd inhibited shoot Fe and Ca phytoaccumulation, whereas AMF and earthworms normalized the status of essential elements in plants. Cd detoxification by earthworm-AMF-S. nigrum symbiosis was manifested by increases in plant biomass accumulation (22–117%), chlorophyll content (17–63%), antioxidant levels (SOD 10–18%, POD 9–25%, total polyphenols 17–22%, flavonoids 15–29%, and glutathione 7–61%). It also ameliorated the photosynthetic capacity, and macro- and micronutrient statuses of plants; markedly reduced the levels of malondialdehyde (20–27%), superoxide anion (29–36%), and hydrogen peroxide (19–30%); and upregulated the transcription level of FeSOD. Thus, the combined action of earthworms and AMF feasibly enhances metal tolerance of hyperaccumulating plants and improves the quality of polluted soil.
Afficher plus [+] Moins [-]Contributions of internal emissions to peaks and incremental indoor PM2.5 in rural coal use households
2021
Men, Yatai | Li, Jianpeng | Liu, Xinlei | Li, Yaojie | Jiang, Ke | Luo, Zhihan | Xiong, Rui | Cheng, Hefa | Tao, Shu | Shen, Guofeng
Indoor air quality is critically important to the human as people spend most time indoors. Indoor PM₂.₅ is related to the outdoor levels, but more directly influenced by internal sources. Severe household air pollution from solid fuel use has been recognized as one major risk for human health especailly in rural area, however, the issue is significantly overlooked in most national air quality controls and intervention policies. Here, by using low-cost sensors, indoor PM₂.₅ in rural homes burning coals was monitored for ~4 months and analyzed for its temporal dynamics, distributions, relationship with outdoor PM₂.₅, and quantitative contributions of internal sources. A bimodal distribution of indoor PM₂.₅ was identified and the bimodal characteristic was more significant at the finer time resolution. The bimodal distribution maxima were corresponding to the emissions from strong internal sources and the influence of outdoor PM₂.₅, respectively. Indoor PM₂.₅ was found to be correlated with the outdoor PM₂.₅, even though indoor coal combustion for heating was thought to be predominant source of indoor PM₂.₅. The indoor-outdoor relationship differed significantly between the heating and non-heating seasons. Impacts of typical indoor sources like cooking, heating associated with coal use, and smoking were quantitatively analyzed based on the highly time-resolved PM₂.₅. Estimated contribution of outdoor PM₂.₅ to the indoor PM₂.₅ was ~48% during the non-heating period, but decreased to about 32% during the heating period. The contribution of indoor heating burning coals comprised up to 47% of the indoor PM₂.₅ during the heating period, while the other indoor sources contributed to ~20%. The study, based on a relatively long-term timely resolved PM₂.₅ data from a large number of rural households, provided informative results on temporal dynamics of indoor PM₂.₅ and quantitative contributions of internal sources, promoting scientific understanding on sources and impacts of household air pollution.
Afficher plus [+] Moins [-]Magnetic poly(β-cyclodextrin) combined with solubilizing agents for the rapid bioaccessibility measurement of polycyclic aromatic hydrocarbons in soils
2021
Qin, Shibin | Qi, Shihua | Li, Xiaoshui | Shi, Qiuyun | Li, Huan | Mou, Xiaoxuan | Zhang, Yuan
The rapid determination of the bioaccessibility of polycyclic aromatic hydrocarbons (PAHs) in soils is challenging due to their slow desorption rates and the insufficient extraction efficiency of the available methods. Herein, magnetic poly(β-cyclodextrin) microparticles (Fe₃O₄@PCD) were combined with hydroxypropyl-β-cyclodextrin (HPCD) or methanol (MeOH) as solubilizing agents to develop a rapid and effective method for the bioaccessibility measurement of PAHs. Fe₃O₄@PCD was first validated for the rapid and quantitative adsorption of PAHs from MeOH and HPCD solutions. The solubilizing agents were then coupled with Fe₃O₄@PCD to extract PAHs from soil-water slurries, affording higher extractable fractions than the corresponding solution extraction and comparable to or higher than single Fe₃O₄@PCD or Tenax extraction. The desorption rates of labile PAHs could be markedly accelerated in this process, which were 1.3–12.0 times faster than those of single Fe₃O₄@PCD extraction. Moreover, a low HPCD concentration was sufficient to achieve a strong acceleration of the desorption rate without excessive extraction of the slow desorption fraction. Finally, a comparison with a bioaccumulation assay revealed that the combination of Fe₃O₄@PCD with HPCD could accurately predict the PAH concentration accumulated in earthworms in three field soil samples, indicating that the method is a time-saving and efficient procedure to measure the bioaccessibility of PAHs.
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