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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.
Mostrar más [+] Menos [-]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
Mostrar más [+] Menos [-]Assessment of the presence of metals and quality of water used for irrigation in Kwara State, Nigeria
2017
Aliyu, Taiye | Balogun, Olusegun | Namani, Chineye | Olatinwo, Lateefat | Aliyu, Abubakar
In Nigeria irrigated agriculture is an important tool for economic growth, food security, and poverty reduction during dry periods of rain-fed agriculture. The concentration and composition of dissolved constituents in water determines its quality for irrigation use. Water quality studies strongly suggest that agriculture is a leading source of water quality problems, due to pesticides and other agro-inputs, widely used by farmers to improve agricultural productivity. Poor quality irrigation water would therefore obviously affect soil quality and crop productivity. This study was carried out in 2015 to assess the presence of metals and physical properties of water, used for irrigation in Kwara state, Nigeria. Samples were randomly collected from thirty irrigation sources in three senatorial zones of Kwara State. The samples were analyzed for the presence of metals and water quality parameters, using standard procedures. Results showed that the highest concentration of Sulphate (7.0mg/L), Nitrate (8.9mg/L), Sodium (31.6mg/L), Calcium (3.1mg/L), and Magnesium (0.7) ions were within acceptable limits. The Sodium Adsorption Ratio, an indicator for water suitability in agricultural irrigation as well as a standard diagnostic parameter for the sodicity hazard of a soil, was significantly the highest (22.7) in Kwara North. Results of the study point to the need for an effective irrigation water quality assessment to curb nonpoint source pollution that could be caused by improper use of chemicals and pesticides by farmers.
Mostrar más [+] Menos [-]Natural radioactivity and heavy metal distribution in reservoirs in Ghana
2017
Darko, Godfred | Ansah, Eugene | Faanu, Augustine | Azanu, David
The present paper has determined the radioactivity concentrations, which are due to natural occurrence of radionuclides along with heavy metal concentration in water, sediment, and fish from 2 reservoirs in Ghana. Heavy metal concentrations in all samples were generally within the WHO safe limits with the average activity concentrations of 238U, 232Th, and 40K in water being respectively 0.42±0.20, 0.33±0.31, and 1.59±1.07 Bq/L in case of Lake Bosomtwe and 0.26±0.14, 0.67±0.34 and 1.47±0.62 Bq/L for Bui Dam in Ghana. The average annual effective dose due to ingestion of radionuclides in water ranged from 20.5 to 156 for Lake Bosomtwe and 26.5 to 162 μSv/year for Bui dam and the absorbed dose rate and annual effective dose, measured for Lake Bosomtwe, was 15.45±2.00 nGy/year and 18.95±2.95 mS/year respectively while in case of Bui dam it accounted to 10.44±4.11 nGy/year and 12.88±5.01 mS/year respectively, found to be within the UNSCEAR recommended limits of 59 nGy/year and 100 mS/year respectively. The observed metal concentrations, within safety limits, imply that metal-associated diseases cannot be expected among patrons of these reservoirs. Therefore, radionuclides and heavy metals levels in the reservoirs are not expected to cause any significant health problem for humans.
Mostrar más [+] Menos [-]Characterization of tannery effluents of Hazaribagh area, Dhaka, Bangladesh
2017
Kabir, Mohammad | A. N. M, Fakhruddin | M. A.Z, Chowdhury | Z., Fardous | Islam, Rashedul
The present investigation characterizes tannery effluents by determining water quality parameters and some selected trace metallic constituents in order to measure the magnitude of environmental pollution. Effluents and sediments have also been used to isolate chromium-resistant bacteria, collected from Hazaribagh area, Dhaka, claimed to be increasing Cr (VI)-enriched environments, and utilized to reduce Cr (VI). The pH, TDS, DO, and EC values of all investigated samples have been within the range of 4.35 to 9.74, 290 to 9,200 mg/L, 1.5 to 4.90 mg/L, and 587 to 19,000 µs/cm, respectively. The concentrations of trace metallic constituents have been determined by means of Atomic Absorption Spectrophotometer (AAS), giving the following ranges: Cr: 14.282 to 6,769.554 mg/L; Cd: 1.546 to 2.214 mg/L; Pb: 18.808 to 32.026 mg/L; Cu: 1.522 to 2.578 mg/L; Zn: 0.682 to 8.688 mg/L; Fe: 1.37 to 108.556 mg/L; and Mn: 3.494 to 17.17 mg/L. The order of trace metallic constituents in the effluent samples was Cr > Fe > Pb > Mn > Zn > Cd > Cu. The water quality parameters and metallic constituents’ concentration were higher than that of standard permissible limits in all the examined samples. The average number of Cr (VI)-resistant bacteria in the sediment samples with glucose (0.5%, w/v) supplementation was 2.35× 103 CFU/gm at 24h. One of the representative isolate was able to tolerate up to 400 mg/L of K2Cr2O7 as Cr (VI). The bacteria, isolated in the present study, can be used as eco-friendly biological agents for the remediation and/or detoxification of chromium (Cr) pollution from the chromium contaminated environments.
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons in air from industrial areas in Lagos and Ogun states, Nigeria
2017
Salaudeen, Ibrahim | Sonibare, Oluwadayo | Sojinu, Samuel | Ekundayo, Olusegun
There is currently scarce information on the occurrence and distributions of Polycyclic Aromatic Hydrocarbons (PAHs) in the air from industrial estates in Nigeria. Hence, the present study aims to evaluate the extent and sources of pollution of polycyclic aromatic hydrocarbons in the air from some industrial estates in Lagos and Ogun States, Nigeria. Ten air samples have been collected from the industrial estates in Lagos (Ogba and Ilupeju) and ten from Ogun (Agbara and Ota) between October and November, 2014, using low volume air sampler. Also five further air samples have been collected from Epe town, located in the outskirts of Lagos, where there are no industrial activities to serve as control. The concentrations and distributions of 20 target Polycyclic Aromatic Hydrocarbons (PAHs) in the air samples have been determined by gas chromatography-mass spectrometry. The concentration of ∑20PAHs ranged from 89.20 to 96.48 ng/m3 (with an average of 92.84 ng/m3) and 72.52 to 142.91 ng/m3 (with an average of 107.72 ng/m3) in the air samples from Lagos and Ogun industrial estates, respectively. The air from the control site has a total ∑20PAHs concentration of 19.55 ng/m3 (9.78 ng/m3 in average). When compared with global data, these values show that the air samples have been moderately polluted. PAHs in most air samples are mainly from pyrolytic sources, which may have resulted from diesel fuel combustion and high vehicular emissions, typical of industrial activities in the area.
Mostrar más [+] Menos [-]Evaluation of oil pollution dispersion in an unsaturated sandy soil environment
2017
Abbasi Maedeh, Pouyan | Nasrabadi, Touraj | Wu, Wei | Al Dianty, Marelianda
The current study assesses critical condition of oil dispassion, considering the unsaturated soil condition dispersity behavior for oil dispersion. The numerical model is used as a finite element method to model the oil spill pollution with two different saturated and unsaturated soil conditions chosen and their pollution dispersion results compared. Extracted results from numerical model show that considering the form of unsaturated soil, by changing the matric suction its soil conductivity ratio will differ. Regarding the current study analysis, it has been observed that the pattern of oil dispersion in case of unsaturated soil can be changed, in comparison to saturated soil condition. The vertical penetration of oil pollution in both cases of saturated and unsaturated soil condition will be more than horizontal dispersion pollution speed. As for oil pollution control in soil domain, the condition of unsaturated soil may be controllable, compared to the saturated one. Extracted results show that oil dispersion velocity, considering saturated soil, is more than 10 times greater than unsaturated one.
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