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Plant uptake and availability of antimony, lead, copper and zinc in oxic and reduced shooting range soil Полный текст
2018
Hockmann, Kerstin | Tandy, Susan | Studer, Björn | Evangelou, Michael W.H. | Schulin, R. (Rainer)
Shooting ranges polluted by antimony (Sb), lead (Pb), copper (Cu) and zinc (Zn) are used for animal grazing, thus pose a risk of contaminants entering the food chain. Many of these sites are subject to waterlogging of poorly drained soils. Using field lysimeter experiments, we compared Sb, Pb, Cu and Zn uptake by four common pasture plant species (Lolium perenne, Trifolium repens, Plantago lanceolata and Rumex obtusifolius) growing on a calcareous shooting range soil under waterlogged and drained conditions. To monitor seasonal trends, the same plants were collected at three times over the growing season. Additionally, variations in soil solution concentrations were monitored at three depths over the experiment. Under reducing conditions, soluble Sb concentrations dropped from ∼50 μg L−1 to ∼10 μg L−1, which was attributed to the reduction of Sb(V) to Sb(III) and the higher retention of the trivalent species by the soil matrix. Shoot Sb concentrations differed by a factor of 60 between plant species, but remained at levels <0.3 μg g−1. Despite the difference in soil solution concentrations between treatments, total Sb accumulation in shoots for plants collected on the waterlogged soil did not change, suggesting that Sb(III) was much more available for plant uptake than Sb(V), as only 10% of the total Sb was present as Sb(III). In contrast to Sb, Pb, Cu and Zn soil solution concentrations remained unaffected by waterlogging, and shoot concentrations were significantly higher in the drained treatment for many plant species. Although showing an increasing trend over the season, shoot metal concentrations generally remained below regulatory values for fodder plants (40 μg g−1 Pb, 150 μg g−1 Zn, 15–35 μg g−1 Cu), indicating a low risk of contaminant transfer into the food chain under both oxic and anoxic conditions for the type of shooting range soil investigated in this study.
Показать больше [+] Меньше [-]Chronic radiation exposure modifies temporal dynamics of cytogenetic but not reproductive indicators in Scots pine populations Полный текст
2018
Geras'kin, Stanislav | Oudalova, Alla | Kuzmenkov, Alexey | Vasiliyev, Denis
Over a period of 13 years (2003–2015), reproductive and cytogenetic effects are investigated in Scots pine populations growing in the Bryansk region of Russia radioactively contaminated as a result of the Chernobyl accident. In reference populations, the frequencies of cytogenetic abnormalities are shown to change with time in a cyclic manner. In chronically exposed populations, the cyclic patterns in temporal dynamics of cytogenetic abnormalities appear to be disturbed. In addition, a tendency to decrease in the frequencies of cytogenetic abnormalities with time as well as an increase in their variability with dose rate is revealed. In contrast, no significant impact of chronic radiation exposure on the time dynamics of reproductive indexes is detected. Finally, long-term observations on chronically exposed Scots pine populations revealed qualitative differences in the temporal dynamics of reproductive and cytogenetic indicators.
Показать больше [+] Меньше [-]The energetic physiology of juvenile mussels, Mytilus chilensis (Hupe): The prevalent role of salinity under current and predicted pCO2 scenarios Полный текст
2018
Duarte, C. | Navarro, J.M. | Quijón, P.A. | Loncon, D. | Torres, R. | Manríquez, P.H. | Lardies, M.A. | Vargas, C.A. | Lagos, N.A.
As a result of human activities, climate forecasts predict changes in the oceans pCO₂ and salinity levels with unknown impacts on marine organisms. As a consequence, an increasing number of studies have begun to address the individual influence of pCO₂ and salinity but much remains to be done to understand their combined effects on the physiology and ecology of marine species. Our study addressed this knowledge gap by measuring the influence of current and predicted levels of pCO₂ (380 and 1200 ppm, respectively) and salinity (20, 25 and 30 psμ) on the energetic physiology of juvenile mussels (Mytilus chilensis) from the south-eastern Pacific region. Our results indicate that a reduced salinity caused a significant reduction in clearance rate, absorption efficiency and scope for growth of this species. Meanwhile, an increase in pCO₂ levels caused a reduction in excretion rates and interacted significantly with salinity in the rate of oxygen uptake measured in the mussel. These results suggest that potential changes in salinity might have a direct role on the physiology of M. chilensis. The effect of pCO₂, although less prevalent among the variables measured here, did interact with salinity and is also likely to alter the physiology of this species. Given the ecological and economic importance of M. chilensis, we call for further studies exploring the influence of pCO₂ across a wider range of salinities.
Показать больше [+] Меньше [-]Short-term transcriptome and microRNAs responses to exposure to different air pollutants in two population studies Полный текст
2018
Espín-Pérez, Almudena | Krauskopf, Julian | Chadeau-Hyam, Marc | van Veldhoven, Karin | Chung, Fan | Cullinan, Paul | Piepers, Jolanda | van Herwijnen, Marcel | Kubesch, Nadine | Carrasco-Turigas, Glòria | Nieuwenhuijsen, Mark | Vineis, Paolo | Kleinjans, Jos C.S. | de Kok, Theo M.C.M.
Diesel vehicle emissions are the major source of genotoxic compounds in ambient air from urban areas. These pollutants are linked to risks of cardiovascular diseases, lung cancer, respiratory infections and adverse neurological effects. Biological events associated with exposure to some air pollutants are widely unknown but applying omics techniques may help to identify the molecular processes that link exposure to disease risk. Most data on health risks are related to long-term exposure, so the aim of this study is to investigate the impact of short-term exposure (two hours) to air pollutants on the blood transcriptome and microRNA expression levels.We analyzed transcriptomics and microRNA expression using microarray technology on blood samples from volunteers participating in studies in London, the Oxford Street cohort, and, in Barcelona, the TAPAS cohort. Personal exposure levels measurements of particulate matter (PM₁₀, PM₂.₅), ultrafine particles (UFPC), nitrogen oxides (NO₂, NO and NOx), black carbon (BC) and carbon oxides (CO and CO₂) were registered for each volunteer. Associations between air pollutant levels and gene/microRNA expression were evaluated using multivariate normal models (MVN).MVN-models identified compound-specific expression of blood cell genes and microRNAs associated with air pollution despite the low exposure levels, the short exposure periods and the relatively small-sized cohorts. Hsa-miR-197-3p, hsa-miR-29a-3p, hsa-miR-15a-5p, hsa-miR-16-5p and hsa-miR-92a-3p are found significantly expressed in association with exposures. These microRNAs target also relevant transcripts, indicating their potential relevance in the research of omics-biomarkers responding to air pollution. Furthermore, these microRNAs are also known to be associated with diseases previously linked to air pollution exposure including several cancers such lung cancer and Alzheimer's disease. In conclusion, we identified in this study promising compound-specific mRNA and microRNA biomarkers after two hours of exposure to low levels of air pollutants during two hours that suggest increased cancer risks.
Показать больше [+] Меньше [-]Sources and distribution of microplastics in China's largest inland lake – Qinghai Lake Полный текст
2018
Xiong, Xiong | Zhang, Kai | Chen, Xianchuan | Shi, Huahong | Luo, Ze | Wu, Chenxi
Microplastic pollution was studied in China's largest inland lake – Qinghai Lake in this work. Microplastics were detected with abundance varies from 0.05 × 10⁵ to 7.58 × 10⁵ items km⁻² in the lake surface water, 0.03 × 10⁵ to 0.31 × 10⁵ items km⁻² in the inflowing rivers, 50 to 1292 items m⁻² in the lakeshore sediment, and 2 to 15 items per individual in the fish samples, respectively. Small microplastics (0.1–0.5 mm) dominated in the lake surface water while large microplastics (1–5 mm) are more abundant in the river samples. Microplastics were predominantly in sheet and fiber shapes in the lake and river water samples but were more diverse in the lakeshore sediment samples. Polymer types of microplastics were mainly polyethylene (PE) and polypropylene (PP) as identified using Raman Spectroscopy. Spatially, microplastic abundance was the highest in the central part of the lake, likely due to the transport of lake current. Based on the higher abundance of microplastics near the tourist access points, plastic wastes from tourism are considered as an important source of microplastics in Qinghai Lake. As an important area for wildlife conservation, better waste management practice should be implemented, and waste disposal and recycling infrastructures should be improved for the protection of Qinghai Lake.
Показать больше [+] Меньше [-]Ambient air quality in the holy city of Makkah: A source apportionment with elemental enrichment factors (EFs) and factor analysis (PMF) Полный текст
2018
Nayebare, Shedrack R. | Aburizaiza, Omar S. | Siddique, Azhar | Carpenter, David O. | Hussain, Mirza M. | Zeb, Jahan | Aburiziza, Abdullah J. | Khwaja, Haider A.
Air pollution remains a major global public health and environmental issue. We assessed the levels of PM₂.₅ and delineated the major sources in Makkah, Saudi Arabia. Fine particulate matter (PM₂.₅) sampling was performed from February 26, 2014–January 27, 2015 in four cycles/seasons. Samples were analyzed for black carbon (BC) and trace elements (TEs). PM₂.₅ source apportionment was performed by computing enrichment factors (EFs) and positive matrix factorization (PMF). Backward-in time trajectories were used to assess the long-range transport. Significant seasonal variations in PM₂.₅ were observed, Spring: 113 ± 67.1, Summer: 88.3 ± 36.4, Fall: 67.8 ± 24, and Winter: 67.6 ± 36.9 μg m⁻³. The 24-h PM₂.₅ exceeded the WHO (25 μg m⁻³) and Saudi Arabia's (35 μg m⁻³) guidelines, with an air quality index (AQI) of “unhealthy to hazardous” to human health. Most delta–C computations were below zero, indicating minor contributions from bio-mass burning. TEs were primarily Si, Ca, Fe, Al, S, K and Mg, suggesting major contributions from soil (Si, Ca, Fe, Al, Mg), and industrial and vehicular emissions (S, Ca, Al, Fe, K). EF defined two broad categories of TEs as: anthropogenic (Cu, Zn, Eu, Cl, Pb, S, Br and Lu), and earth-crust derived (Al, Si, Na, Mg, Rb, K, Zr, Ti, Fe, Mn, Sr, Y, Cr, Ga, Ca, Ni and Ce). Notably, all the anthropogenic TEs can be linked to industrial and vehicular emissions. PMF analysis defined four major sources as: vehicular emissions, 30.1%; industrial-mixed dust, 28.9%; soil/earth-crust, 24.7%; and fossil-fuels/oil combustion, 16.3%. Plots of wind trajectories indicated wind direction and regional transport as major influences on air pollution levels in Makkah. In collusion, anthropogenic emissions contributed >75% of the observed air pollution in Makkah. Developing strategies for reducing anthropogenic emissions are paramount to controlling particulate air pollution in this region.
Показать больше [+] Меньше [-]Implications of co-contamination with aged heavy metals and total petroleum hydrocarbons on natural attenuation and ecotoxicity in Australian soils Полный текст
2018
Khudur, Leadin S. | Gleeson, Deirdre B. | Ryan, Megan H. | Shahsavari, Esmaeil | Haleyur, Nagalakshmi | Nugegoda, Dayanthi | Ball, A. S.
The bioremediation of historic industrial contaminated sites is a complex process. Co-contamination, often with lead which was commonly added to gasoline until 16 years ago is one of the biggest challenges affecting the clean-up of these sites. In this study, the effect of heavy metals, as co-contaminant, together with total petroleum hydrocarbons (TPH) is reported, in terms of remaining soil toxicity and the structure of the microbial communities. Contaminated soil samples from a relatively hot and dry climate in Western Australia were collected (n = 27). Analysis of soils showed the presence of both contaminants, TPHs and heavy metals. The Microtox test confirmed that their co-presence elevated the remaining ecotoxicity. Toxicity was correlated with the presence of lead, zinc and TPH (0.893, 0.599 and 0.488), respectively, assessed using Pearson Correlation coefficient factor. Next Generation Sequencing of soil bacterial 16S rRNA, revealed a lack of dominate genera; however, despite the variation in soil type, a few genera including Azospirillum spp. and Conexibacter were present in most soil samples (85% and 82% of all soils, respectively). Likewise, many genera of hydrocarbon-degrading bacteria were identified in all soil samples. Streptomyces spp. was presented in 93% of the samples with abundance between 7% and 40%. In contrast, Acinetobacter spp. was found in only one sample but was a dominant member of (45%) of the microbial community. In addition, some bacterial genera were correlated to the presence of the heavy metals, such as Geodermatophilus spp., Rhodovibrio spp. and Rubrobacter spp. which were correlated with copper, lead and zinc, respectively. This study concludes that TPH and heavy metal co-contamination significantly elevated the associated toxicity. This is an important consideration when carrying out risk assessment associated with natural attenuation. This study also improves knowledge about the dynamics of microbial communities in mixed contamination scenarios.
Показать больше [+] Меньше [-]Functional activity and functional gene diversity of a Cu-contaminated soil remediated by aided phytostabilization using compost, dolomitic limestone and a mixed tree stand Полный текст
2018
Xue, Kai | Zhou, Jizhong | Van Nostrand, Joy | Mench, Michel | Bes, Clemence | Giagnoni, Laura | Renella, Giancarlo
Functional activity and functional gene diversity of a Cu-contaminated soil remediated by aided phytostabilization using compost, dolomitic limestone and a mixed tree stand Полный текст
2018
Xue, Kai | Zhou, Jizhong | Van Nostrand, Joy | Mench, Michel | Bes, Clemence | Giagnoni, Laura | Renella, Giancarlo
Trace elements (TEs) availability, biochemical activity and functional gene diversity was studied in a Cu-contaminated soil, revegetated for six years with a mixed stand of willow, black poplar, and false indigo-bush, and amended or not with compost plus dolomitic limestone (OMDL). The OMDL amendment significantly reduced Cu and As availability and soil toxicity, and increased the biochemical activity and microbial functional diversity assessed with the GEOCHIP technique, as compared to the unamended soil (Unt). The OMDL soil showed significantly higher abundance of 25 functional genes involved in decomposition organic compounds, and 11, 3 and 11 functional genes involved in the N, P and S biogeochemical cycles. Functional gene abundance was positively correlated with nutrient contents but negatively correlated with Cu availability and soil toxicity. The abundance of microbial functional genes encoding for resistance to various TEs also increased, possibly due to the microbial proliferation and lower Cu exposure in the presence of high total soil Cu concentration. Genes encoding for antibiotic resistance due to the co-occurrence of TEs and antibiotic resistant genes on genetic mobile elements. Overall, phytomanagement confirmed its potential to restore the biological fertility and diversity of a severely Cu-contaminated soil, but the increase of TEs and antibiotic resistant gene abundances deserve attention in future studies.
Показать больше [+] Меньше [-]Functional activity and functional gene diversity of a Cu-contaminated soil remediated by aided phytostabilization using compost, dolomitic limestone and a mixed tree stand Полный текст
2018
Xue, Kai | Zhou, Jizhong | van Nostrand, Joy | Mench, Michel | Bes, Clémence | Giagnoni, Laura | Renella, Giancarlo | Chinese Academy of Sciences (CAS) | University of Oklahoma (OU) | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB) | Università degli Studi di Firenze = University of Florence = Université de Florence (UniFI) | ANR-15-SUSF-0007,INTENSE,Intensify production, transform biomass to energy and novel goods and protect soils in Europe(2015)
International audience | Trace elements (TEs) availability, biochemical activity and functional gene diversity was studied in a Cu-contaminated soil, revegetated for six years with a mixed stand of willow, black poplar, and false indigo-bush, and amended or not with compost plus dolomitic limestone (OMDL). The OMDL amendment significantly reduced Cu and As availability and soil toxicity, and increased the biochemical activity and microbial functional diversity assessed with the GEOCHIP technique, as compared to the unamended soil (Unt). The OMDL soil showed significantly higher abundance of 25 functional genes involved in decomposition organic compounds, and 11, 3 and 11 functional genes involved in the N, P and S biogeochemical cycles. Functional gene abundance was positively correlated with nutrient contents but negatively correlated with Cu availability and soil toxicity. The abundance of microbial functional genes encoding for resistance to various TEs also increased, possibly due to the microbial proliferation and lower Cu exposure in the presence of high total soil Cu concentration. Genes encoding for antibiotic resistance due to the co-occurrence of TEs and antibiotic resistant genes on genetic mobile elements. Overall, phytomanagement confirmed its potential to restore the biological fertility and diversity of a severely Cu-contaminated soil, but the increase of TEs and antibiotic resistant gene abundances deserve attention in future studies.
Показать больше [+] Меньше [-]RETRACTED: Signalling cross-talk between nitric oxide and active oxygen in Trifolium repens L. plants responses to cadmium stress Полный текст
2018
Liu, Shiliang | Yang, Rongjie | Tripathi, Durgesh Kumar | Li, Xi | Jiang, Mingyan | Lv, Bingyang | Ma, Mingdong | Chen, Qibing
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors-in-Chief.The authors have plagiarized part of a paper that had appeared in Plant, Cell & Environment, 29 (2006) 1532–1544. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3040.2006.01531.x The images that were reused were: Figures 1e, 1f, 1g, 1h, 2a, 2b, 2e, 2f.One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
Показать больше [+] Меньше [-]Spatiotemporal variations in macrofaunal assemblages linked to site-specific environmental factors in two contrasting nearshore habitats Полный текст
2018
Bae, Hanna | Lee, Jung-Ho | Song, Sung Joon | Ryu, Jongseong | Noh, Junsung | Kwon, Bong-Oh | Choi, Kyungsik | Khim, Jong Seong
A long-term study on a benthic community was conducted in two different localities, one in semi-enclosed bay of Jinhae (n = 10, south coast) and the other in open sea area of Samcheok (n = 10, east coast), Korea, respectively. We aimed to identify the spatiotemporal patterns of macrozoobenthos and the environmental variables influencing such patterns in the two contrasting habitats. The macrozoobenthos assemblages on the soft bottom of the subtidal zone were analyzed over the 3 years, encompassing 12 consecutive seasons, in 2013–2016. Among the 22 environmental variables measured, organic matter, dissolved oxygen, mean grain size, and water depth showed clear differences between two study areas. Accordingly, several ecological indices (such as the number of species, abundance, dominant species, and diversity index (H’)) generally reflected site-specific benthic conditions. The macrofaunal community in the Jinhae showed typical seasonal fluctuations, whereas the Samcheok community showed no significant change over time and space. Region- or site-dependent temporal variabilities of macrofaunal assemblages are depicted through cluster analysis (CA), indicating distinct temporal changes in the composition of dominant species. In particular, the abundance of some dominant species noticeably declined in certain seasons when several opportunistic species peaked. Such faunal succession might be explained by significant changes to specific environmental factors, such as bottom dissolved oxygen, grain size, and water depth. Principle component analysis further identified major environmental factors, i.e., sediment properties in Jinhae and water quality parameters in Samcheok community, respectively. In addition, discriminant analysis confirmed the presence of several site-specific parameters for the faunal assemblage groups identified through CA. Finally, indicator value analysis identified species that were representative across stations and regions in accordance with their habitat preference and/or species tolerance. Overall, the two contrasting nearshore habitats showed distinct community differences, in time and space, that were influenced by site-dependent environmental conditions.
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