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[The recent flora of vascular macrophyta in the "Vrbas-Bezdan" and "Banatska Palanka-Novi Becej" canals [Serbia, Yugoslavia] as indicator of ecological characteristics and water quality]
1997
Stojanovic, S. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Vuckovic, M. | Zderic, M. | Stankovic, Z. | Kilibarda, P. | Lazic, D.
[Hydrophytes of the Tisza river [Serbia, Yugoslavia] with respect to by bioindication]
1999
Stojadinovic, S. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Kilibarda, P. | Nikolic, Lj. | Lazic, D.
In this paper there were given research results obtained during many years of investigation of hydrophytes of the Tisza river, Serbia (Yugoslavia), and their bioindicating values. The plant world of the Tisza river is characterized by floristical diversity, with three characteristics band: band of submerged, band of floating and band of emerged hydrophytes. Among submerged plants these are distinguished by abundance, covering values and occurrence degree: Ceratophyllum demersum, Elodea canadaensis, Potamogeton crispus, Potamogeton perfoliatus and Potamogeton pectinatus. In the floating band species of the fam. Lemnaceae: Lemna minor, Lemna gibba, Spirodela polyrrhiza and Potamogeton fluitans are most frequent. In the closest coastal band, these species are most frequent: Typha angustifolia, Typha latifolia, Phragmites communis, Sagittaria sagittifolia and Typhoides arundinacea. On the basis of determined floristical composition and bioindicating values there can be noticed the organic pollution increasing trend.
اظهر المزيد [+] اقل [-]PM2.5 induces intestinal damage by affecting gut microbiota and metabolites of rats fed a high-carbohydrate diet
2021
Liu, Jinhua | Su, Xianghui | Lu, Jianjiang | Ning, Jianying | Lin, Meng | Zhou, Hongjuan
PM₂.₅ has a major impact on the gastrointestinal system, but the specific mechanism behind this action is not fully understood. Current studies have focused on the relationship between PM₂.₅ and intestinal flora disorder, while ignoring the important influence of diet on gut microbes. In this study, SD rats were fed either a normal, high-fat, or high-carbohydrate diet for two months and exposed to PM₂.₅ (7 mg/kg b.w.) by intratracheal instillation. The results showed that the body and kidney weights of the rats in the high-fat diet group were significantly increased relative to those with a normal diet, and changes in the intestinal microbes and metabolites induced by PM₂.₅ were observed. Rats in the high-carbohydrate diet group had a significant response, and the diversity and richness indices of the flora were reduced (p < 0.05); additionally, intestinal Biffidobacterium and Lactobacillus were enriched, while many endogenous metabolites were found. Some amino acids derivatives and long-chain fatty acids were increased (p < 0.05). Both diet structure and PM₂.₅ exposure can affect the composition of gut microbiota, and intestinal metabolites may be associated with cell membrane damage when a high-carbohydrate diet interacts with PM₂.₅. This study considers multiple dietary factors to further supplement the evidence of intestinal damage via PM₂.₅.
اظهر المزيد [+] اقل [-]The prolonged disruption of a single-course amoxicillin on mice gut microbiota and resistome, and recovery by inulin, Bifidobacterium longum and fecal microbiota transplantation
2020
Lin, Huai | Wang, Qing | Yuan, Meng | Liu, Lei | Chen, Zeyou | Zhao, Yanhui | Das, Ranjit | Duan, Yujing | Xu, Ximing | Xue, Yingang | Luo, Yi | Mao, Daqing
The usages of antibiotics in treating the pathogenic infections could alter the gut microbiome and associated resistome, causing long term adverse impact on human health. In this study, mice were treated with human-simulated regimen 25.0 mg kg⁻¹ of amoxicillin for seven days, and their gut microbiota and resistome were characterized using the 16S rRNA amplicons sequencing and the high-throughput qPCR, respectively. Meanwhile, the flora restorations after individual applications of inulin, Bifidobacterium longum (B. longum), and fecal microbiota transplantation (FMT) were analyzed for up to 35 days. The results revealed the prolonged negative impact of single course AMX exposure on mice gut microbiota and resistome. To be specific, pathobionts of Klebsiella and Escherichia-Shigella were significantly enriched, while prebiotics of Bifidobacterium and Lactobacillus were dramatically depleted. Furthermore, β-lactam resistance genes and efflux resistance genes were obviously enriched after amoxicillin exposure. Compared to B. longum, FMT and inulin were demonstrated to preferably restore the gut microbiota via reconstituting microbial community and stimulating specific prebiotic respectively. Such variation of microbiome caused their distinct alleviations on resistome alteration. Inulin earned the greatest elimination on AMX induced ARG abundance and diversity enrichment. FMT and B. longum caused remove of particular ARGs such as ndm-1, blaPER. Network analysis revealed that most of the ARGs were prone to be harbored by Firmicutes and Proteobacteria. In general, gut resistome shift was partly associated with the changing bacterial community structures and transposase and integron. Taken together, these results demonstrated the profound disruption of gut microbiota and resistome after single-course amoxicillin treatment and different restoration by inulin, B. longum and FMT.
اظهر المزيد [+] اقل [-]A single indicator of noxiousness for people and ecosystems exposed to stable and radioactive substances
2019
Beaugelin-Seiller, Karine | Gilbin, Rodolphe | Reygrobellet, Sophie | Garnier-Laplace, Jacqueline
Inspired by methods used for life cycle impact assessment (LCIA), we constructed a series of indicators to appreciate the noxiousness of radioactive materials and wastes for human and ecosystem health. According to known potential human health and ecological effects of such materials, six main impact categories were considered to initiate the development of the method: human cancer and non-cancer effects vs. ecotoxicity, considering both chemotoxicity and radiotoxicity. For ecosystems, the noxiousness indicator is based on the concept of Potentially Affected Fraction (PAF), used as a damage indicator at the ecosystem level. The PAF express the toxic pressure on the environment due to one substance. It has been enlarged to mixtures of substances as multi-substances PAF (ms-PAF), and applied to a mix of stable and radioactive substances. Combining ecotoxicity data and a simplified model of exposure of fauna and flora, we proposed a chemotoxicity indicator and a radiotoxicity indicator, ultimately aggregated into a single indicator simply by addition.According to acknowledged practices in LCIA and corresponding available data, we suggested implementing to human health an approach similar to that applied to ecosystems. We produced eigth basic indicators combining effects categories (cancer and non cancer), exposure pathways (ingestion and inhlation) and substances (chemicals and radionuclides). The principle of additivity supporting the whole proposed approach allows their complete aggregation into a single indicator also for human health. Different source terms may be then easily directly compared in terms of human and ecological noxiousness.Applied to the time evolution of a High Level radioactive Waste (HLW), the method confirmed over 1 million years the dominance of the radiotoxicity in the noxiousness of the material for both humans and environment. However there is a change with time in the ranking of the most noxious substances, with stable metals contribution going progressively up. Finally, the HLW global noxiousness, integrating human health and ecological aspects, was assessed through time at three stages and showed a temporal decrease as expected from the dominance of the radiotoxicity.
اظهر المزيد [+] اقل [-]Air pollution during the winter period and respiratory tract microbial imbalance in a healthy young population in Northeastern China
2019
Li, Xinming | Sun, Ye | An, Yunhe | Wang, Ran | Lin, Hong | Liu, Min | Li, Shuyin | Ma, Mingyue | Xiao, Chunling
In order to investigate the relationship between air pollution and the respiratory tract microbiota, 114 healthy volunteers aged 18–21 years were selected during the winter heating period in Northeast China; 35 from a lightly polluted region (group A), 40 from a moderately polluted region (group B) and 39 from a heavily polluted region (group C). Microbial genome DNA was extracted from throat swab samples to study the oral flora composition of the volunteers by amplifying and sequencing the V3 regions of prokaryotic 16S rRNA. Lung function tests were also performed. The relative abundance of Bacteroidetes and Fusobacteria were significantly lower and Firmicutes Proteonacteria and Actinobacteria higher in participants from polluted regions. Within bacteria classes, Bacterioida abundance was lower and Clostridia abundance higher in polluted areas, which was also reflected in the order of abundance. In samples from region C, the abundance of Prevotellaceae, Veillonellaceae, Porphyromonadaceae, Fusobacteriaceae Paraprevollaceae and Flavobacteriaceae were lowest among the 3 regions studied, whereas the abundance of Lachnospiraceae and Ruminococcaceae were the highest. From group A to group C, the relative class abundances of Prevotella, Veillonella, Fusobacterium, Camphylobacter and Capnocytophaga Porphyromonas, Peptostreptococcus and Moraxella became lower in polluted areas.Pulmonary function correlated with air pollution and the oropharyngeal microbiota differed within regions of high, medium and low air pollution. Thus, during the winter heating period in Northeast China, the imbalance of the oropharyngeal microbiota might be caused by air pollution and is likely associated with impairment of lung function in young people.
اظهر المزيد [+] اقل [-]Bacteriological and geochemical features of the groundwater resources: Kettara abandoned mine (Morocco)
2019
Zouhri, Lahcen | El Amari, Khalid | Marier, David | Benkaddour, Abdelfattah | Hibti, Mohamed
Waste water of the Kettara village, as well as the abandoned tailings, constitute a potential environmental issue with direct consequences on air, soil, water resources qualities and, on human health. In this paper, experimental investigations examine the environmental impact which is induced by the wastewater, mine tailings and the lithological factors of rocks. This multidisciplinary research allows to i) understand the transfer of the Metallic Trace Elements (selenium, arsenic, nickel and zinc) and sulfate ions in the fractured shales media, ii) to assess the water potability by using the microbiological analysis. The microbiological results reveal the domestic impact by the presence of several kinds of bacteria in the groundwater resources: E. coli, Fecal coliforms, Total coliforms, Enterococci, Mesophilic Aerobic Flora, Sulphite-reducing bacteria and Salmonella.Selenium, arsenic and the bacteriological contamination of the groundwater could be explained by five kinds of factors: i) the geological formations and the nature of the hydrogeological system (unconfined layer), ii) the groundwater flow, the hydraulic relation between the hydrogeological wells and, the fractures network in the shale aquifer. The piezometric map allows to highlight the groundwater flow from the North-East to North-West and to the South-West, the drainage axis towards the P21 well and the presence of the dividing axis in the contaminated zone by the arsenic, iii) the absence of the unhealthy habitats with permeable traditional septic tanks in the village; iv) the transfer of the spreading animal excrements from the soil to groundwater and, v) the migration of the wastewater towards downstream of the groundwater flow. The presence of the reed beds could explain the reduction of bacteria in the hydrogeological wells of the study area.
اظهر المزيد [+] اقل [-]Assessing biochar's ability to reduce bioavailability of aminocyclopyrachlor in soils
2014
Rittenhouse, Jennifer L. | Rice, Pamela J. | Spokas, Kurt A. | Koskinen, William C.
Aminocyclopyrachlor is a pyrimidine carboxylic acid herbicide used to control broadleaf weeds and brush. Amending soil with activated charcoal is recommended to prevent off-site transport of aminocyclopyrachlor and non-target plant damage. We used the batch-equilibrium method to determine the concentration of aminocyclopyrachlor in a pseudo-steady state with biochar, soil, and biochar-soil systems (<10% biochar by weight). We observed that aminocyclopyrachlor is mobile in soils. Soil incorporation of activated charcoal removed nearly all of the aqueous aminocyclopyrachlor thereby limiting its bioavailability to non-target flora. On the other hand, biochars were less effective than activated charcoal. Biochar produced from olive mill waste feedstock was the most effective biochar that we assessed for reducing the aqueous herbicide concentration. Although these biochars reduced the aminocyclopyrachlor concentration, they would not be practical remediation media due to the extraordinarily high application rates required to reduce the concentration by 50% (2.13 × 105 kg ha−1–7.27 × 105 kg ha−1).
اظهر المزيد [+] اقل [-]Assessment of heavy metal and metalloid levels and screening potential of tropical plant species for phytoremediation in Singapore
2022
Wang, Yamin | Tan, Swee Ngin | Mohd Yusof, Mohamed Lokman | Ghosh, Subhadip | Lam, Yeng Ming
Heavy metal or metalloid contamination is a common problem in soils of urban environments. Their introduction can be due to unpremeditated anthropogenic activities like atmospheric deposition produced by diffuse sources, construction activities and landscape maintenance. Phytoremediation is a rapidly evolving, sustainable approach to remediate the contaminated lands where metals and metalloids are highly persistent in the environment. The present work sets out to determine the level of 12 heavy metals and metalloids (As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb and Zn) in soil and their accumulation by plant foliage found in nature parks and industrial sites in Singapore. The latter also involve the investigation of the remediation capacity of selected tropical plant species found at the sampling sites. The study is done using digestion and inductively coupled plasma-optical emission spectrometry. Eleven soil sampling sites across Singapore with 300 sampling points were selected, where soil (0–10 cm) and plant foliage samples were collected. Bioconcentration factors were determined to assess the phytoremediation potential of the collected plant species. Toxicity risk of heavy metals were assessed by comparing the target and intervention values from the soil quality guidelines by the Dutch Standard. Results of the study revealed there were regions where levels of heavy metals and metalloids were relatively high and could affect the environment and the health of flora and fauna in Singapore. Our study discovered that there were available tropical plant species (e.g., wildflowers, ferns and shrubs) which could potentially play a significant role in the remediation of contaminated lands that could open up a huge possibility of developing a sustainable and environmentally-friendly way of managing this emerging urban problem. Results showed that 12 plant species, including hyperaccumulator like Pteris vittata, Centella asiatica, were effective for the accumulation of heavy metals and metalloids.
اظهر المزيد [+] اقل [-]Interactions and effects of microplastics with heavy metals in aquatic and terrestrial environments
2021
Khalid, Noreen | Aqeel, Muhammad | Noman, Ali | Khan, Shujaul Mulk | Akhter, Noreen
Contamination of waters and soils with microplastics (MPs) is an emerging environmental issue worldwide. MPs constitute a cocktail of various additives and polymers besides adsorbing toxic heavy metals from the environment. This co-occurrence of MPs with heavy metals poses a threat to the health of organisms and is poorly understood. Ingestion of MPs contaminated with heavy metals may also result in subsequent transfer of heavy metals up in the food chain. MPs surfaces play a crucial role in the adsorption of heavy metals. Aged/biofouled MPs facilitate greater adsorption of metals and certain microplastic (MP) polymers adsorb some metals more specifically. External factors involved in the process of adsorption/accumulation of heavy metals are the solution pH, salinity, and the concentration of relevant heavy metals in the media. Desorption greatly depends upon pH of the external solution. This is more concerning as the guts/digestive systems of organisms have low pH which could enhance the desorption of toxic metals and making them accumulate in their bodies. The aim of this article is to discuss the abundance, distribution, adsorption, and desorption behavior of MPs for heavy metals, and their combined toxic effects on flora and fauna based on the limited research on this topic in the literature. There is an overarching need to understand the interactions of MPs with heavy metals in different ecosystems so that the extent of ecotoxic effects they pose could be assessed which would help in the environmental regulation of these pollutants.
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