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Metals and metalloids in high-altitude Pyrenean lakes: sources and distribution in pre-industrial and modern sediments
2023
Rodriguez-iruretagoiena, Azibar | Gredilla, Ainara | Fdez-ortiz De Vallejuelo, Silvia | Arana, Gorka | Meaurio, Maite | Madariaga, Juan Manuel | Auguet, Jean Christophe | González González, Aridane | Pokrovsky, Oleg S. | Camarero, Luis | De Diego, Alberto
High-altitude Pyrenean lakes are ecosystems far from local pollution sources, and thus they are particularly sensitive to the atmospheric deposition of metals and metalloids. This study aims to quantify the effect of human activity in 18 lakes located in both side of the France–Spain frontier. Sediment cores were collected in summer 2013, sampled at a 1cm resolution and the concentration of 24 elements was measured by ICP-MS. Statistic and chemometric analysis of the results highlights the influence of the geographical position and lithogenic features of each lake basin on trapping pollutants. More than the 80% of the lakes showed values of enrichment factor (EF) above 2 for at least one of the elements investigated in at least one core interval, which corroborates the existence of historical anthropogenic inputs of elements in the studied area. The results demonstrate the natural origin of As and Ti in Pyrenees, together with the significant anthropogenic inputs of Cd, Pb, Sb and Sn from ancient times. The data set points mining activities as the main historical source of pollution and illustrate the large impact of the industrial revolution. The regional variability could reflect also differential long-range transport, followed by dry or wet deposition.
Afficher plus [+] Moins [-]Kinetics of metal and metalloid concentrations in holopelagic Sargassum reaching coastal environments
2023
Cipolloni, Océanne-amaya | Baudrimont, Magalie | Simon-bouhet, Benoît | Dassié, Émilie Pauline | Gigault, Julien | Connan, Solène | Pascal, Pierre-yves
Since 2011, the Caribbean Islands have experienced unprecedented stranding of a pelagic brown macroalgae Sargassum inducing damages for coastal ecosystems and economy. This study measures the kinetics of metal trace elements (MTE) in Sargassum reaching different coastal environments. In July 2021, over a period of 25 days, fixed experimental floating cages containing the three Sargassum morphotypes (S. fluitans III and S. natans I and VIII) were placed in three different coastal habitats (coral reef, seagrass, and mangrove) in Guadeloupe (French West Indies). Evolution of biomasses and their total phenolic content of Sargassum reveals that environmental conditions of caging were stressful and end up to the death of algae. Concentrations of 19 metal(loid) trace elements were analyzed and three shapes of kinetics were identified with the MTE that either concentrate, depurate, or remains stable. In the mangrove, evolution of MTE was more rapid than the two other habitats a decrease of the As between 70 and 50 μg g−1 in the mangrove. Sargassum natans I presented a different metal composition than the two other morphotypes, with higher contents of As and Zn. All Sargassum morphotype are rapidly releasing the metal(oid)s arsenic (As) when they arrive in studied coastal habitats. In order to avoid the transfer of As from Sargassum to coastal environments, Sargassum stranding should be avoided and their valorization must take into account their As contents.
Afficher plus [+] Moins [-]Exposure of zebrafish to an environmental mixture of persistent organic pollutants triggers an increase in anxiety-like syndrome but does not affect boldness in unexposed offspring
2023
Alfonso, Sebastien | Blanc, Melanie | Cousin, Xavier | Bégout, Marie-laure
Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants (POPs) that are present as complex mixtures in all environmental compartments, including aquatic ecosystems. However, little is known about the effects of such complex mixtures on teleost behaviour. In this study, zebrafish (Danio rerio) were chronically exposed to an environmentally relevant mixture (MIX) containing 22 PCB and 7 PBDE congeners through diet from 5 days post fertilization onwards. MIX-exposed F0 fish produced offspring (F1 and F2 generations) that were fed using plain food and grown until adulthood. In each generation, five behavioural traits (i.e. boldness, activity, sociality, exploration and anxiety) were evaluated by the mean of different experimental set-ups. Two distinct behavioural syndromes were identified: boldness, positively correlated to activity and exploration; and anxiety, associated with low sociality. F0 fish did not display any behavioural disruption resulting from POP exposure whereas F1 MIX fish were bolder than fish from other generations but did not differ significantly from F1 controls. F2 MIX fish displayed a higher anxiety syndrome than F2 controls. This is of particular importance since such behavioural changes in offspring generations may have persistent ecological consequences, may affect fitness and hence cause detrimental effects on wild fish populations exposed to POP mixtures.
Afficher plus [+] Moins [-]Comparative Assessment of Medical Waste Management in Multi-System and Selected Teaching Hospitals in Ekiti State, Nigeria
2023
Oyebode, O.J. | Okpala, C.C. | Ajibade, S.M. | Ogarekpe, N.M. | Afolalu, S.A. | Coker, A.O. | Udeagbara, S.G. | Adeniyi, A.T.
Medical facilities, such as hospitals, clinics, and locations where diagnosis and treatment are administered, create dangerous waste that predisposes individuals to deadly infections. Medical waste management aims to improve health and prevent public health and environmental threats. Questionnaires, interviews, site visitations, and observations were utilized to determine the management strategies implemented in the three hospitals and evaluate the efficacy of waste management. The hospitals under review are Afe Babalola University Multi-system Hospital (AMSH), Ekiti State University Teaching Hospital (EKSUTH), and Federal Teaching Hospital Ido-Ekiti (FETHI). Statistical Package for the Social Sciences (SPSS) was utilized for the statistical analysis of the questionnaires, and the mean assessment was utilized to compute the waste per bed each day. The results revealed that the three hospitals’ sharp, infectious, and pharmaceutical waste is the most sorted. All hospitals burn their medical waste in incinerators but dispose of the ashes in dumpsites. The mean evaluation of all hospitals’ medical waste was weighed to establish the overall amount generated. The total amount of medical waste created at AMSH, EKSUTH, and FETHI is 31.5 kg, 53.6 kg, and 135.1 kg, respectively. The medical waste generated per bed per day in AMSH, EKSUTH, and FETHI is 0.61 kg, 0.74 kg, and 0.73 kg, respectively. It was determined that the proper management and disposal of waste is a critical obligation of healthcare facilities. There should be a provision for educating personnel about the consequences of inappropriately disposing of medical waste.
Afficher plus [+] Moins [-]Efficacy of Nanofertilizers Over Chemical Fertilizers in Boosting Agronomic Production
2023
Khatri, A. | Bhateria, R.
Global agricultural production cannot catch the increasing population’s exigency. At different times, the world has faced food crises of varying intensity. Many steps have been taken after that to encounter the rising concerns. Nowadays, nanofertilizers are being experimented with as an alternative to conventional fertilizers. Nanofertilizers can be classified as macronutrients and micronutrients nanofertilizers. Synthesis of macronutrient nanofertilizers (nitrogen, phosphorus, potassium, calcium, magnesium, etc.) and micronutrient nanofertilizers (iron, boron, zinc, copper, silicon, etc.) can be done using chemical and green synthesis methods, which involves reducing agents, capping agents, dendrimers, microbial synthesis, solvents, and others. Composition of the nanofertilizers can be done using top-down and bottom-up approaches incorporating hydrocarbon polymer, dendrimers, microbes, etc., which decides their usage in various crops depending upon the requirement of the plant. Engineered nanofertilizers can improve crop yield by mitigating environmental pollution, environmental stress, and plant diseases. However, the unsystematic use of nanofertilizers can be a hurdle in its utilization. This article discusses various types of nanofertilizers with their unique properties and applications. Each category of nanofertilizers is explained considering their composition, particle size, concentrations applied, benefited plant species, and plant-growth enhancement aspects.
Afficher plus [+] Moins [-]Assessment of Sodium Chloride (NaCl) Induced Salinity on the Growth and Yield Parameters of Cichorium intybus L.
2023
Khan, A. | Khan, A. A. | Samreen, S. | Irfan, M.
The present study was done on the hypothesis that excess sodium chloride (NaCl) in the soil decreases the growth and yield of Cichorium intybus L. To investigate this hypothesis, a pot experiment was conducted in which chicory seeds were sown in garden soil-filled earthen pots and treated with three different doses of sodium chloride (45, 75, and 105 mM kg-1 soil) except the control, and each treatment was replicated three times. The results revealed that all the saline treatments significantly (p≤0.05) reduced the vegetative (including root and shoot length, dry weight, number of leaves, leaf area, number of branches, and photosynthetic pigments) and reproductive (mean fruit number/plant, mean seed number/fruit, and total seed yield/plant) growth parameters of Cichorium intybus. On increasing NaCl concentration in the soil, chlorophyll content significantly (p≤0.05) decreased while proline content in the fresh leaves increased significantly (p≤0.05). From the results, it is concluded that Cichorium intybus L. can tolerate a moderate level of sodium chloride stress (45-75 mM NaCl kg-1 soil) but is sensitive to high doses of sodium chloride stress (105 mM NaCl kg-1 soil).
Afficher plus [+] Moins [-]Effects of Corn Straw Biochar, Soil Bulk Density and Soil Water Content on Thermal Properties of a Light Sierozem Soil
2023
Li, Y. Q. | Li, L. J. | Zhao, B. W. | Zhao, Y. | Zhang, X. | Dong, X.
This research aimed to quantify the effects of biochar derived from corn straw on soil thermal conductivity, capacity, and diffusivity. Firstly, the amount of biochar application (w/w) added to light sierozem soil was 0% to 5%, and the mixtures were packed into soil columns at a consistent bulk density (1.20 g.cm-3). Secondly, soil columns with a consistent biochar addition rate (5%) were packed to different bulk densities of 1.30, 1.25, 1.20, 1.15, and 1.10 g.cm-3. Soil thermal characteristics were measured under the control of soil moisture content from 0% to 40%. Under consistent bulk-density conditions, biochar could significantly reduce soil thermal conductivity and diffusivity. Still, there wasn’t a significant influence on soil heat capacity in most soil moisture content levels. With the decrease of soil bulk density, soil thermal conductivity, capacity, and diffusion coefficient reduced significantly. As soil water content increased, all the indexes of thermal properties largely improved, and the effects were much more significant than those of biochar amendment and bulk density change on soil thermal performances. This research could supply an implication to evaluate the influence of biochar amendment on soil thermal performances.
Afficher plus [+] Moins [-]Moringa Oleifera Coagulation Characteristics in Wastewater Treatment in a University Dormitory
2023
Ogunshina, M. S. | Abioye, O. M. | Adeniran, K. A. | Olasehinde, D. A.
Wastewater treatment necessitates the use of an appropriate method to achieve satisfactory results. The conventional method of Alum addition has been widely used for years, but it is prohibitively expensive. This study uses Moringa oleifera, an inexpensive and readily available plant, as a natural coagulant to treat wastewater collected from university dormitories. Physicochemical parameters such as pH, Turbidity, Electrical Conductivity (EC), Total Dissolved Solids (TDS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and Dissolved Oxygen (DO) were examined based on appropriate standards. Wastewater treatment with varied coagulant dosages of 50, 100, and 150 mg.L-1) was monitored using a standard jar test device with an initial wastewater perturbation at 100 rpm for 5 min was reduced to 50 rpm in 10 minutes with a rest time of 30 min. The results showed that the quality of the physicochemical properties of the water improved. The percentage increase in the water quality is; BOD (92%), COD (92%), and TDS (52-64%), with an increase in Moringa coagulant achieving a reduction of 96% of Turbidity. While the DO improved (79%), the pH remained below acceptable limits (6.73-7.56) for effluent disposal. The treated water showed clarity (colorless) and no odor compared to the wastewater. Hence, Moringa oleifera seeds cake residue can be an effective coagulant for wastewater treatment.
Afficher plus [+] Moins [-]Tests for Evaluating the Efficacy of Phosphoric Acid Activated Charcoals from Two Biomasses
2023
Jadhav, Abhijit S. | Nalawade, Ravindra
Good quality activated charcoals were prepared from areca nutshell and coconut shell using phosphoric acid as a chemical activating agent at 400oC. Physico-chemical properties like iodine number, methylene blue number, and surface area of two activated charcoals were measured to assess the porous nature. A special test called acetic acid number was devised to understand the quality of functional groups on charcoal surfaces. Proximate analysis and physical properties of the two activated charcoals closely matched those of a commercial sample, confirming the good quality of samples prepared in the laboratory. Adsorption of isolated caramel from waste stream obeyed Freundlich isotherm, and the data could be explained based on the physisorption of large size molecules on the walls of mesoporous solid surface. Adsorption of methylene blue involving Coulombic attraction towards the areca nut shell-derived activated charcoal could be predicted and confirmed based on the acetic acid number for the first time.
Afficher plus [+] Moins [-]Comparative Assessment and Monitoring Changes in NDVI of Achanakmar Tiger Reserve (ATR) and its Buffer Zone, India
2023
Mahato, Anupama
Achanakmar Tiger Reserve (ATR), endowed with rich biological diversity and lush green vegetation in and around, makes it more unique. It is also an integral part of the Achanakmar Amarkantak Biosphere Reserve (AABR) and has been identified as one of the important tiger reserves of the Central Indian landscape due to its connectivity with other protected areas and tiger reserves in neighboring landscapes. Vegetation mapping and monitoring are important to understand changes in ecosystem processes and associated temporal and spatial impacts. Pre- and post-monsoon IRS, LISS III, and AWiFS satellite data from 2000, 2004, 2008, 2010, and 2013 were used for the present study. This paper is an attempt to examine the variation in the normalized difference vegetation index (NDVI) of ATR and its buffer zone on a seasonal and temporal basis. Climate conditions such as temperature, precipitation, relative humidity, etc. play an important role in the growth and development of healthy vegetation. The NDVI value of ATR has shown fluctuation and recorded positive growth over the past 14 years with few exceptions. The post-monsoon season recorded a higher NDVI value as compared to the pre-monsoon months. The maximum NDVI value was recorded in 2004 (+0.539) for the entire ATR and its buffer zone.
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