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Assessment of Solid Waste Management Practices in Bahir Dar City, Ethiopia
2018
Birara, E. | Kassahun, T.
Even though solid waste management has become a major public health and environmental concern in urban areas of Ethiopia, only 2% of the population receive solid waste management services. The primary objective of this study is to assess solid waste management practices of Bahir Dar City. The technique of multistage random sampling has been employed to draw 350 households for this study, with both quantitative and qualitative primary data put into good use. Finally, the quantitative data has been analyzed by means of descriptive statistics with the results indicating that 78% of the respondents feel that the current solid waste management service is far below the required level; whereas, 22% of the respondents show satisfaction with the existing waste management service. The municipality has planned to provide solid waste management service for the residents once a week, but the survey results demonstrate that only 29% of the sample households received solid waste management services weekly, indicating that the performance of solid waste management service is low. Among 350 households, a sum of 66.6% practice illegal solid waste disposal with the remaining 33.4% waiting until solid waste collectors come to the area to take the waste away. Therefore, participation of urban households, micro and small enterprises, and governmental and non-governmental organizations plays a great role to upgrade the existing low status of solid waste management services.
显示更多 [+] 显示较少 [-]Anthropogenic share of metal contents in soils of urban areas
2018
Fazeli, G. | Karbassi, A.R. | khoramnejadian, Sh. | Nasrabadi, T.
In the present investigation, 41 soil samples were subjected to single step chemical partitioning to assess the lithogenic and non-lithogenic portions of metals in Tehran's soils. The share of various studied metals in the anthropogenic portion ranges from as low as 0.2% to as high as 85% of bulk concentration. Geo-accumulation index (Igeo) showed that Cd falls within "heavily contaminated" soils. It might be inferred that Ni, Cu, Cr, Zn, Co and Ca fall within "Deficient to minimal" class in accordance with enrichment factor (EF) classification.. Enrichment factor values (to some extents) match with the chemical partition studies results (except for Ni and Cr). The very low Ca content of soil samples could be indicative of low biological productivity in the Tehran's soil. Also the very low concentrations of Mn could be indicative of reducing environment in soils of Tehran.
显示更多 [+] 显示较少 [-]Evaluation of seasonal variability in surface water quality of Shallow Valley Lake, Kashmir, India, using multivariate statistical techniques
2017
Najar, Ishtiyaq | Khan, Anisa | Hai, Abdul
Seasonal variation in water quality of Anchar Lake was evaluated using multivariate statistical techniques- principal component analysis (PCA) and cluster analysis (CA). Water quality data collected during 4 seasons was analyzed for 13 parameters. ANOVA showed significant variation in pH (F3 = 10.86, P < 0.05), temperature (F3 = 65, P <0.05), Electrical conductivity (F3 = 32.72, P <0.05), Calcium (F3 = 36.84, P <0.05), Magnesium (F3 = 16.52, P <0.05), nitrate-nitrogenSeasonal variation in water quality of Anchar Lake has been evaluated, using two multivariate statistical techniques, namely Principal Component Analysis (PCA) and Cluster Analysis (CA). Water quality data, collected during four seasons, have been analyzed for 13 parameters and ANOVA has shown that pH (F3= 10.86, P < 0.05), temperature (F3 = 65, P < 0.05), electrical conductivity (F3= 32.72, P < 0.05), Calcium (F3= 36.84, P < 0.05), Magnesium (F3= 16.52, P < 0.05), nitrate-nitrogen (F3= 48.06, P < 0.05), ammonical nitrogen (F3 =198.75, P < 0.05), and dissolved oxygen (F3= 4.96, P < 0.05) varied by season, whereas the substantial variations of sodium (F2= 7.18, P <0.05), phosphate-phosphorous (F2= 25.31, P < 0.05), biological oxygen demand (F2= 11.02, P < 0.05), and chemical oxygen demand (F2=37.73, P < 0.05) were based on different sites. CA has grouped the three sampling sites throughout the four seasons into three clusters of similar water quality as relatively Less-Polluted (LP), Medium-Polluted (MP), and Highly-Polluted (HP). In addition, PCA has been applied on the extract to recognize the factors, responsible for water quality variations in four seasons of the year, resulting in four principal components for winter, summer, and autumn, five ones for spring, accounting for 79.58%, 89.07%, 83.34%, and 93.13% of total variance respectively. Thus the factors, responsible for water quality variation, are mainly related to domestic wastewaters, seasonal variation, agricultural runoff, and catchment geology. These results will help decision-makers better understand the influence of various factors on water quality and manage pollution/eutrophication adaptively in Anchar Lake.
显示更多 [+] 显示较少 [-]Responses of Accessions of Zea Mays to Crude Oil Pollution Using Growth Indices and Enzyme Activities as Markers
2017
Njoku, K. L
The performance of every plant in an environment is an indicator of how the plant can withstand the various environmental conditions. This study investigated the toxicity of crude oil on the growth performance, chlorophyll contents, enzymatic activities and oxidative stress biomarkers of eight accessions of Zea mays. The growth enzyme (amylase and invertase) activities, as well as oxidative stress biomarkers (malondialdehyde, peroxidase, superoxide dismutase and catalase) in Z. mays were assayed using spectrophotometric method. The maize accessions were grown in the experimental pots containing crude oil treatments (2%, 4%, 6%, 8% and 10%) and harvested after 14 days of seedling emergence. The results showed that the percentage seedling emergence, leaf area, root length, stem girth and shoot length of each accession were significantly reduced (p
显示更多 [+] 显示较少 [-]Spectrophotometer-based student education program on health hazard assessment due to Cr(VI) and Pb contamination in surface and groundwaters of Hyderabad City, India
2015
Das Sharma, Mala | Juyal, Archana | Karuna, Mantha | Das Sharma, Subrata
A student-centric research education program with the active participation of undergraduate students is initiated. The aim is to imbibe ―responsible citizenship behavior‖ in them so that each member becomes conscious and well trained to take up environmental-related issues and challenges for long-term sustainability of the ecosystem. In this work, we report spectrophotometer-based estimation of hexavalent chromium (57-268 gL-1) and lead (34–158 gL-1) concentrations in different surface waters and groundwater samples in and around the city of Hyderabad, India. Our results indicate that the studied surface water bodies and aquifers are contaminated to variable degrees and pose a serious threat to the ecosystem. In view of low geochemical baseline values for chromium and lead, the origin of heavy metal pollution is inferred to be anthropogenic, mainly originating from industrial effluents. The toxicological data are integrated with health data for risk assessment and impending health hazard. Finally, the novelty of this student-centric research program is highlighted.
显示更多 [+] 显示较少 [-]Polycyclic Aromatic Hydrocarbons In Bottom Sediments Of Donuzlav Lake (Black Sea)
2023
Soloveva, Olga | Tikhonova, Elena | Barabashin, Timofey
Lake Donuzlav, located in the western part of the Crimean Peninsula is a water body undergoing anthropogenic load, which cannot but affect the state of its bottom sediments. The content and composition of polycyclic aromatic hydrocarbons (PAH) are representative indicators of the degree and character of an anthropogenic impact in natural habitats. The aim of the work was to assess the level of PAH content in the bottom sediments, to identify potential sources and to assess the toxicity of bottom sediments. It was established that the average content of ∑PAH in the sediments amounted to 806±380 ng/g, with the values of this parameter ranging over 34–4036 ng/g. At five out of ten stations in Lake Donuzlav, PAH values, average for the Black Sea, were exceeded. These stations were grouped along both banks in the inner part of the reservoir. Fourteen PAHs were identified: Nap, 2mNap, Flu, Phe, Ant, Fla, Py, TrPhe, Chr, BbF, BkF, BaP, DBA, BghiP. The main share falls on the binuclear Nap and 2mNap, which indicate the presence of fresh oil pollution. The average share of these compounds over the water area was 60±5%, and at stations with elevated levels of ∑PAH it was 74±4%. There was a close correlation between the content of all polyarenes, which coefficient averaged 0,88. The presence of geochemical relationships between polyarenes entering from different sources was probably due to the functioning of natural mechanisms aimed at the transformation of pollutants, which served to restore the dynamic balance of the system.
显示更多 [+] 显示较少 [-]Hazard Estimations Result from Arsenic Contamination in Common Foodstuffs, Soil, Sediment, and Water of Joypurhat District, Bangladesh
2023
Khatun, Nazma | Hossain, Mohammad | Islam, Md Didarul | Rahaman, Ashiqur
We analyzed 125 samples collected from Joypurhat district, Bangladesh, in this study. Average inorganic arsenic (IAs) content obtained from collected polished rice, tomato, potato, radish, and arum leaves 0.31 - 0.91, 0.24 - 0.61, 0.49 - 0.88, 0.40 - 0.93, and 0.30 - 0.69 mg/kg, respectively. This report summarized that almost every agronomic sample contains arsenic; the As contents remain within the permissible limit set by FAO/WHO’s guideline (1.00 mg/kg) except for the rice sample. The As concentration for the rice sample was significantly higher (0.31 - 0.91) than the prescribed limit (0.20 mg/kg). But, the As level for water (mean range, 0.10 - 0.72 mg/l), sediment (0.13 - 0.53 mg/kg), and soil samples (24.1 - 43.1 mg/kg) also significantly surpassed the permissible level. The present study is alarming for water samples, where the highest IAs concentration (0.72 mg/l) is 72 times [14 times] higher than WHO/FAO’s [Bangladesh’s] allowable limit (0.01mg/l) [0.05 mg/l]. All agronomic fields contain higher IAs (25.50 - 43.10 mg/kg) than the world standard limit (10 mg/kg). Statistical Igeo confirmed the moderate pollution of the entire agronomic field of Joypurhat except for the river’s sediment. Again, EF values ensured the anthropogenic pollution by the moderately severe enrichment of As for the 65% agronomic field and significant enrichment of As for the 35% agronomic field. Hazard estimation results revealed the privileged possibility of non-carcinogenic [carcinogenic] health hazards to regular polished rice [water] consumers. So, present study suggests that authorities should take necessary steps to prevent contamination/upcoming health risks.
显示更多 [+] 显示较少 [-]Experimental Investigation of Pb Release Characteristics in Zn-Pb Mine Tailings under Simulated Leaching Conditions, Anguran, Iran
2023
Akhavan, Ahmad | Golchin, Ahmad
The aim of this research was to use a variety of leaching methods to see how different parameters affected the amount of lead leaching from tailings. Synthetic precipitation leaching procedure, toxicity characteristic leaching procedure, leachate extraction procedure, and field leach test protocols were utilized to assess the toxicity of the tailings. The impact of the liquid-solid ratio, particle size, contact time, and pH on lead release from tailings was also investigated. According to the findings, pH entirely effects on the release of lead from the tailings, and amphoteric leaching behavior was observed. The tailings were classified as hazardous material as a result of the TCLP leaching protocol's findings. S1 and S2 samples had lead mobility indexes of 51% and 5.6%, respectively. The solubility process influenced the discharge of lead from the tailings. In the particle size ranges of 0.3-0.5 mm and 0.6-1.0 mm, respectively, the maximum amount of lead was released from S1 and S2 samples. Various experiments have shown that the interaction between different factors will have complex and strong effects on the leaching process. To that end, managing of tailings and preventing lead emission into the environment necessitates a unique technique. Leachability is affected by a number of factors and often multiple factors can produce synergistically different releases than would be predicted by each factor alone. However, validation of the leaching approaches to field-collected and monitored cases indicates that combined effects are either captured by the test data or can be considered through fate and transport modeling.
显示更多 [+] 显示较少 [-]Effect of Copper on Cadmium-Resistant Plants of Agrostis stolonifera
2023
Aleksandrovich Gladkov, Evgeny | Nikolaevna Gladkova, Olga
Environmental pollution with heavy metals has a negative impact on lawn grasses. Heavy metals are one of the priority pollutants of anthropogenic ecosystems. Earlier, plants Agrostis stolonifera, resistant to cadmium, were obtained using biotechnological method. Plants that are resistant to one heavy metal may be cross-resistant to another. The assessment of the resistance of plants obtained by biotechnological methods to other heavy metals is of practical value. The object of our study was to lawn grass - Agrostis stolonifera L. The aim of this work was to assess the tolerance of the next generation descendants of the regenerant Agrostis stolonifera, resistant to cadmium, to one of the most phytotoxic heavy metals - copper. Cadmium -tolerant plants were more resistant to copper. The tolerance of cadmium – resistant plants to copper is associated with nonspecific mechanisms. However, the increase in plant resistance was not very significant. Therefore, it is more expedient to obtain plants that are resistant to copper.
显示更多 [+] 显示较少 [-]Effect of Auto Road on Spatial Metal Distribution in Dust and Snow Cover
2023
Ankomah Baah, Gabriel | Savin, Igor | Rogova, Olga
The present investigation examined the impact of highways on the global dispersion patterns of metallic elements present in dust and snow. A total of 18 mixed snow samples were collected from both sides of the Moscow-Tambo-Astrakhan Caspian Highway by the end of the winter season. The analysis of the samples indicated the presence of 35 distinct chemical elements, where Al, Ba, Ca, Fe, K, Mg, Na, and Zn were identified as the primary contaminants. The primary area of pollution on the windward side originating from the road spans a distance of 20-40 meters, while on the leeward side, it extends to 10 meters. The data presented suggests that the metals found in highways exhibited variability in terms of their solubility in water and concentration. Our findings demonstrate that the predominant wind directions affect the dispersion of pollutants. Furthermore, it was observed that the region with a higher concentration of metal on the side of the road facing the wind had a thickness that was 2-3 times less than that of the opposite side. It is advisable to conduct a subsequent inquiry within the ensuing five years to obtain dependable data regarding the extent of metal pollution.
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