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An Assessment of Sea Surface and Seabed Macro Plastic Density in Northeastern Mediterranean Sea
2022
Yılmaz, Ayşe Bahar | Demirci, Aydın | Akar, Özkan | Kılıç, Ece | Uygur, Necdet | Şimşek, Emrah | Yanar, Alper | Ayan, Onur Alptekin
Increasing plastic usage pose a significant threat to the marine environment. Many studies have been conducted to examine the amount and environmental impacts of plastic waste across the world. This study was carried out to investigate the density and quality of plastics on the sea surface and seabed of İskenderun Bay. 35 different seabed sampling and 25 different sea surface sampling were conducted by using İskenderun Technical University R/V ISTE-1 vessel. A total of 1 661 581 m2 and 465 511 m2 swept from the seabed and sea surface were scanned, respectively. As a result of these scans, the amount of plastic waste density per unit area of the seabed was found as 0.126 g / m2 ± 0.011 (p: 0.95), and the amount of plastic waste density per unit area of sea surface was calculated as 0.052 gr ± 0.011 (p: 0.95). Scuba dives conducted in river mouths showed plastic deposition pits at the seabed. Major surface current systems and dominant southern winds were found to be effective in the sea surface distribution of plastic materials.
Mostrar más [+] Menos [-]Geochemical Indices for the Assessment of Chemical Contamination Elements in Sediments of the Suches River, Peru
2022
Salas-Mercado, Dante | Hermoza-Gutierrez, Marian | Belizario-Quispe, Germán | Chaiña, Fermín | Quispe, Edgar | Salas-Ávila, Dante
The purpose of this study was to evaluate the concentrations of potentially toxic elements in the Suches river using standardized geochemical indices and to identify the main sources of contamination in the section from the Suches lagoon up to 33.8 km downstream of the effluent river, in the district of Cojata, Puno, Peru. The concentration of Al, Ba, Co, Fe, M, Ni, P, V and Zn in sediments of the Suches river was determined by means of mass spectrometry from October 2019 to February 2020. The values of Co, Fe, Mn, Ni, P and Zn exceeded the base values of contamination according to the general geological references while Al, Ba and V, did not surpass them. The contamination factor showed that the elements Co and Ni revealed a very high level of contamination, while the Zn, a considerable level. The area has an average pollution load index value of 2.24, indicating moderate general pollution. The elements Co, Ni, Al and Zn were within the moderate and extreme classification according to the pollution index. The Spearman's correlation analysis allowed determining the association between Al, Fe, Mn, P and V, which share a natural origin and the accumulation of these elements is due to the effects of weathering and soil erosion. The evaluation of the contamination indices and the correlation confirm that Cobalt, Nickel and Zinc are toxic elements associated with gold mining and agricultural activities.
Mostrar más [+] Menos [-]Myco-remediation of Dairy Wastewater by Naturally Attenuated Aspergillus sp. Responsible for Sulfate Reduction
2022
Sharma, Neha | Meher, Alok Kumar | Bhagwani, Harshita | Chahar, Darshan | Yadav, Neetu | Kohli, Vipra | Shourie, Bhavyam | Arunachalam, Kalirajan | Siankuku, Munaska
Dairy industries generate enormous volumes of waste water which are significantly rich in organic compounds; contributing to high BOD, COD and sulfates. As a mandate to ‘treat’ effluents generated by different unit operations in a dairy industry, current treatment methods rely on physico-chemical, mechanical and conventional biological interventions. This approach remains unviable because of cost intensiveness and excessive energy usage. Additionally, the significant lowering of pollution indicators remains a daunting task with inlet and outlet parameters. With these identifiable gaps, our study was aimed to screen bio-efficacious, naturally attenuated fungal isolates to lower exceeding levels of sulfate in effluents released by dairy industry. Effluent samples were collected from Effluent Treatment Plant (ETP) of Jaipur Dairy, Rajasthan Dairy Co-operation Limited (RCDF), Jaipur. For mycological investigations, qualitative screening was carried out in Potato Dextrose Agar (PDA) supplemented with Calcium Sulfate (CaSo4) (0.1g/L). The most promising fungal isolates belonging to Aspergillus sp. was characterized based on its cultural and microscopic characteristics. Microcosm study was conducted by supplementing Aspergillus sp. in Untreated Dairy Effluent (UDE) for a period of 7 days at Room Temperature (RT) under static conditions. Following the incubation phase, mycelial mesh (plug) was indicative of exponential fungal growth. Effluent seeded with Aspergillus sp. and abiotic controls were spinned at 5000 rpm for 15 minutes to eliminate biomass. Sulfate estimation was carried out in Cell Free Extract (CFE) of both experimental and control group. A significant reduction of 67.3% was observed (p<0.05) with respect to positive control and 8.4% when contrasted with abiotic control.
Mostrar más [+] Menos [-]Kinetic Characteristics and the Performance of Up-Flow Biological Aerated Filters (UBAF) for Iraqi Municipal Wastewater
2022
Kalash, khairi R. | Al-Furaiji, Mustafa | Ahmed, ِAmer N.
This study utilized kinetic models to study the treatment efficiencies of a laboratory-scale up-flow biological aerated filters reactor (UBAF). The treatment efficiency of a model reactor was studied using different operating conditions of the hydraulic retention times, organic loading rates, and kinetic parameters. As a result of the calculations, the second-order and modified Stover/Kincannon models are appropriate. The substrate removal rate constant K2(S) was 1.7 per day for the reactor, with a correlation coefficient of 0.9979. Utilizing the modified Stover/Kincannon model, the coefficient of the determined concentration was 0.9987; 0.9265; and 0.9685 for Chemical oxygen demand (COD); ammonium nitrogen (NH4+-N); and Total Nitrogen (TN), respectively. The calculation of the saturation value constants and maximum utilization rate for Chemical oxygen demand (COD); ammonium nitrogen (NH4+-N); and Total Nitrogen (TN) was performed using the modified Stover-Kincannon model were 178.57 and 201.80 for COD; 1.876 and 4.6 for NH4 +-N; 3.823 and 6.644 for TN, respectively. It is possible to determine the kinetic parameter for removing COD, NH4+-N, and TN from wastewater by using the modified Stover-Kincannon model.
Mostrar más [+] Menos [-]Removal of Colour and COD in Biologically pre-treated Leachate using Activated Carbon from Corn Cobs
2022
Thongkrua, Suchanya | Suriya, Patcharapohn
Activated carbon was prepared from corn cob agricultural waste with different impregnation ratios and pyrolysis times. The optimal adsorbent prepared using at 4:1 ZnCl2:corn cob char ratio at a temperature of 800 °C for 180 min provided the maximum Brunauer-Emmett-Teller (BET) surface area, total pore volume and average pore width, with values of 912.47 m2/g, 0.52 cm3/g and 22.61 Å, respectively. ZnCl2 was effective in creating well-developed pores on the surface of the activated carbon. The removal efficiency and adsorption capacity of the colour and the chemical oxygen demand (COD) of the biologically pre-treated leachate were examined utilizing the best corn cob activated carbon (CCAC) with varying CCAC dosages, contact times and initial pH values. The greatest colour and COD removal effectiveness were 88.6±0.2% and 83.7±0.4%, respectively, at the optimum CCAC dosage of 12 g for 40 min with an initial pH value of 10. In addition, maximum adsorption capacities were achieved for colour and COD of 10.3±0.02 mg/g and 12.6±0.05 mg/g, respectively, under the same conditions. The kinetics of colour and COD adsorption fitted very well with pseudo-second-order kinetic model. The CCAC performs well as an adsorbent for removing colour and COD in biologically pre-treated leachate.
Mostrar más [+] Menos [-]Health Risks of Ecosystem Services in Ologe Lagoon, Lagos, Southwest Nigeria
2022
Yahaya, Tajudeen | Muhammad, Alkali | Onyeziri, Joy Ada | Abdulazeez, Abdulmalik | Shemshere, Ufuoma | Bakare, Tayo | Yusha’u, Bello Kalgo
Ologe Lagoon is one of Lagos, Nigeria’s five major lagoons, which provide essential ecosystem services such as agriculture, fishing, transportation, salt and sand mining, tourism, and industrial development. There are concerns, however, that the lagoon’s water may not be safe for the ecosystem functions it offers. As a result, the physicochemical properties, heavy metal concentrations, and microbial loads of water samples from the lagoon, as well as their health risks, were examined in this study. Physicochemical analysis showed that calcium, chloride, nitrates, sulphate, dissolved oxygen, acidity, alkalinity, total dissolved solid, and total suspended solid were present within the World Health Organization permissible limits, but not so for phosphate and temperature. The heavy metal analysis revealed that the water had non-permissible levels of iron, cadmium, chromium, nickel, manganese, and copper, but lead was normal. The microbiological examination showed abnormal bacteria counts, while coliform and fungus were not detected. The average daily oral and dermal exposure to cadmium, chromium, and nickel were higher than the recommended daily intake, but iron, lead, and copper were within the limits. The hazard quotient of oral and dermal exposure to cadmium, dermal exposure to chromium, and oral exposure to manganese were higher than the recommended limit (> 1). The carcinogenic risks of Cd, Cr, and Ni were also greater than the acceptable limit. The results obtained indicate that Ologe Lagoon’s water is unsafe for the lagoon’s ecosystem functions. Relevant agencies should ensure that waste is treated before being discharged into the lagoon.
Mostrar más [+] Menos [-]Ecological State of the Water Area in the Fresh Water – Saline Water Mixing Zone in Spring (the River Chernaya Estuary – Sevastopol Bay, Black Sea)
2022
Tikhonova, Elena | Burdiyan, Nataliya | Soloveva, Olga | Kotelyanets, Ekaterina | Mironov, Oleg | Guseva, Elena | Gurov, Konstantin
The paper provides data on spatial distribution of petroleum hydrocarbons, heterotrophic and hydrocarbon-oxidizing bacteria in water and bottom sediments as well as on heavy metals in bottom sediments at different sites in the zone of fresh and saline water mixing, with the salinity range 1–18 ‰ during spring low water and high water. Physical and chemical characteristics of the bottom sediments are given. The highest hydrocarbon-oxidizing bacteria percentage of the heterotrophic bacterioplankton count in the indicated areas was found in April, with the maximum of 55 % determined in the transition zone waters. The share of hydrocarbon-oxidizing bacteria in the heterotrophic bacteria abundance in the water was larger than that in the bottom sediments. The highest concentrations of chloroform-extractable substances and petroleum hydrocarbons were detected in the marine zone bottom sediments, and their lowest concentrations were found in the river zone. During the period under study, the petroleum hydrocarbon input (in almost equal volumes) was constant, which is indicated by the hydrocarbon percentage of chloroform-extractable substances, which on average was 31 % for the marine zone, 29 % for the transitional zone, and 32 % for the river zone. In contrast to the river and transition zones, the concentration of chloroform-extractable substances observed in the marine zone bottom sediments was constant.
Mostrar más [+] Menos [-]The state of metallic contamination of Saf-Saf river sediments (Skikda – Algeria)
2022
Rouidi, Sonia | Hadef, Azzedine | Dziri, Hamdi
The sediments of Saf-Saf river (North eastern of Algeria), were studied in order to evaluate their degree of contamination by trace metal elements. Six heavy trace metals (Cd, Cr, Cu, Fe, Mn and Ni) were researched at the surface sediments of nine study stations. Since these different metallic elements appear as tracers of anthropogenic pollution; various evaluation indices of metallic contamination were studied (Igeo, FC, DC, IPS and PEC). The results of these indices are consistent and reveal a polymetallic sediment contamination by several heavy metals essentially by Fe, Mn and Cd, with an abundance of Fe and Mn. Sediment pollution index, indicates that sediments at all stations are hazardous (IPS ˃ 20). The environmental quality of Saf-Saf river sediments, were realized by comparing the metal contents with the values of the TEC and the PEC has showed that the metals Cd, Cu and Mn present a great danger of toxicity.
Mostrar más [+] Menos [-]Screening and Absolute Quantification of a β-lactamase Resistance Gene NDM-1 in Lake Sediment
2022
Ranjan, Rajeev | Thatikonda, Shashidhar
New Delhi Metallo-β-lactamase-1(NDM-1) is an enzyme that hydrolyzes a wide range of β-lactams antibiotics, including carbapenems. The presence of the NDM-1 inhibits the potential of β–lactam antibiotics in treating infections caused by bacterial strains carrying such resistances, thus leaving minimal treatment options available. Due to this, the rapid distribution of NDM-1 harboring bacteria accounts for a significant public health menace worldwide. These bacteria have been detected in clinical specimens and environmental compartments where bacterial infections are ubiquitous. In this study, identification and absolute quantification of NDM-1 in sixteen lake sediment samples collected in and around Hyderabad, India, was carried out using a real-time quantitative polymerase chain reaction (qPCR), and the results were expressed in gene copy number/ng (nanogram) of template DNA. Thirteen samples (out of sixteen) displayed a positive signal for NDM-1 during the qPCR analysis with the highest gene copy number/ng of template DNA (71.8) being observed in the Amberpet STP. Three samples, samples from Durgamcheru lake, Kandi lake, and Singur dam, were negative for the NDM-1 during the qPCR analysis. Hierarchical clustering analysis was performed to categorize the sampling location into different clusters based on pollution sources and the observed results were expressed in the form of a dendrogram.
Mostrar más [+] Menos [-]Quality water not everywhere: Exploratory Analysis of Water Quality Across Ebocha-Obrikom Oil and Gas Flaring Area in the Core Niger Delta Region of Nigeria.
2022
Raimi, Morufu | Sawyerr, Henry | Ezekwe, Clinton | Opasola, Afolabi
Objectives:To compare water quality parameters in the vicinity of Gas Flaring Area of Ebocha-Obrikom of Rivers State with that of the recommended standards.Methods:The research utilized standard analytical procedures. All sampling, conservation, transportation and analysis followed standard procedures described in APHA (2012). All the samples collected were transported to the laboratory through keeping in an icebox to prevent degradation of the organic substances.Results:Result depicts that Turbidity, DO, BOD, COD, TSS, Magnesium, Iron, Cadmium, Lead, Chromium, and Nickel exceeded the desirable limit meant for drinking purpose as well as could potentially pose threats toward human society. Hence, remain unsuitable for drinking, as the inhabitants were more vulnerable for their total lifetime period of exposure through continuous consumption of unsuitable drinking water.Conclusion:It is recommended that the local government environmental health officers and other regulatory agencies frequently monitor the levels of these pollutants within the area and also ensure strict adherence to guidelines to ensure a healthy environment. As exposure to the above stated parameters can have a remarkable impact on human health living in the vicinity of the gas flaring area by drinking water around the study area; thus, groundwater needs to treated before using for household purpose or drinking. Thus, this study would help in decision making for stakeholders and relevant authorities in the execution of reasonable groundwater management strategies and remediation plans in the area to protect public and environmental health.
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