Background and Objective: In the aquatic environment, pesticides are the most studied class of organic toxins but their management has received little attention.The efficacy of activated carbon formed from sawdust as an adsorbent for pesticide removal from industrial wastewater was investigated as well as the effectiveness of conventional wastewater treatment processes for pesticide removal.It also compared the adsorbentʼs efficiency to activated carbon that is commercially available.Materials and Methods: The SEM-EDX, FTIR and the brunauer-emmett-teller (BET) analyzer were used to analyze sawdust-activated carbon (SAC) made from locally available sawdust.Batch adsorption experiment on simulated solutions of 2,2-Dichlorovinyl-dimethyl-phoshate (DDVP) at varied concentrations (0.001, 0.005, 0.01, 0.1 and 0.5 mg LG 1 ) using SAC.Other variables including pH, adsorbent dose and contact time were optimized.Results: The pH was 7.2±0.14,ash content was 3.1±0.00,moisture content was 2.0±0.32%,Brunner Emmett Teller surface area was 736±0.00m 2 gG 1 , micropore volume was 0.3131±0.00m 3 gG 1 and bulk density was 0.55±0.00,according to the SAC.In the untreated and company-treated wastewater samples, the percentage recoveries for DDVP were 86±0.71 and 88±1.41,respectively.In the adsorption of DDVP from industrial wastewater, the optimum parameters obtained during the simulation experiment were used.Sawdust activated carbon has higher adsorption efficiencies (89.06±0.014and 88.62±0.962)than commercial activated carbon (80.94±2.744and 77.50±0.410)for both untreated and company-treated wastewater, according to the findings.Conclusion: The sawdust-activated carbon can be used as a low-cost, high-performance and environment-friendly adsorbent when compared to commercial activated carbon for the removal of DDVP from wastewater.
Background and Objective: Reduced indoor air quality is a burden in schools because of the large number of pupils per classroom, especially in government-owned schools.This work investigated microbial indoor air quality in 25 randomly selected classrooms of five public primary schools and their general toilets.Materials and Methods: Institutional based cross-sectional study was conducted between April and June, 2021 to evaluate the bacterial and fungal load of these rooms using the settle plate method.An Independent sample Mann-Whitney U test was implemented on the data.Results: In the morning, school 1 primary 2 and primary 1 had the lowest and highest hemolytic bacterial count of 1.3×10 4 and 3.1×10 4 CFU mG 3 , respectively.School 1primary 4 and toilet had the lowest and highest staphylococcal count of 8.1×10 3 and 8.0×10 4 CFU mG 3 .School 1 primary 4 and toilet had the highest fungal count of 1.3×10 3 and 1.8×10 4 SFU mG 3 .Bacteria presumptively identified were Streptococcus pneumoniae, Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Streptococcus pyogenes, Staphylococcus epidermidis and Enterococcus faecalis.Fungi presumptively identified were Aspergillus fumigatus, Aspergillus niger, Cladosporium sphaerospermum and Aspergillus flavus.Mann-Whitney U test revealed that the distribution of bacteria count using blood agar is significantly different from mannitol salt agar.Conclusion: High microbial load was found in government public primary schools in the Akure City of Nigeria in comparison to indoor air biological standards of WHO.This indicates a high risk of air-borne infections to government school pupils and a call for attention by stakeholders in authority.
Climate change is generally considered attributable to numerous causes. Human induced climate change is particularly linked to anthropogenic activities that emit greenhouse gases such as carbon dioxide to the atmosphere. The energy sector, due to its heavy reliance on fossil fuels, constitutes one of the largest carbon dioxide contributors to climate change. The mitigation of climate change requires the implementation of many measures. A great number of these are related to energy processes. In this article, the mitigation of climate change and the role played by energy actions in this task is examined. Further, measures are described that are considered crucial by the author for combatting climate change.
Background and Objective: The precise knowledge of the wet front during groundwater infiltration is necessary in order to estimate infiltration problems in irrigation, in natural or artificial recharge of aquifers as well as in water resources management.The model of Green and Ampt (GA) is a simplified natural form of the one-dimensional vertical infiltration problem and it is used systematically for the estimation of the water front in general.It is proved that the model of Green and Ampt is exact for a medium in which the moisture diffusivity is a Dirac function (delta-function medium).The purpose of this study was to present a new explicit approximate solution of the GA model, that can be used for small as well as for large values of time and cumulative infiltration.Materials and Methods: Because of the implicit form of the GA model, many approximate solutions have been developed, with various degrees of precision.In the present paper, a new explicit approximate solution of the GA model is presented, based on models of Philip and Valiantzas, which are improved by introducing new parameters and by using the conjugate gradient method.Results: The comparison of the new model with other approximate models, with the GA model, as well as with experimental data, shows that it confronts very well to practical problems of Hydraulics.Conclusion: The new model gives the possibility to be used not only in border irrigation problems but also in problems of artificial or natural recharge of aquifers and-more generally-water resources management in respect to other models.
Background and Objective: Land-filling is considered as a common method for disposal of Municipal Solid Waste (MSW) and the landfills are regarded as repository of various groups of important microbes growing on organic waste materials.In temperate regions due to lower environmental temperatures the landfill sites are inhabited by a distinct group of bacteria that utilize the wastes as energy sources through the secretion of important cold active enzymes.Hence, the present study was taken to examine physicochemical and bacteriological characterization of organic municipal waste samples collected form landfill site.Materials and Methods: A total of 15 waste samples mixed with soil were randomly collected from the landfill site.The waste samples were analyzed for various physicochemical parameters by following available standard methodology.The isolation of bacteria was done by following serial dilution and spread plate method at temperature of 15EC, pH 7.0 and incubation period of 48 h.Results: The results of the study revealed that the landfill wastes at the surface were partially decomposed by the presence of diverse group of cold active bacterial isolates.The morphological characterization of the isolates revealed that most of bacteria belonged to genus Bacillus (gram+) majority of which produced two important types of cold active enzymes (CMCases, proteases) in response to different substrates (carboxymethyl cellulose and skim milk) under in vitro conditions.Conclusion: It was concluded that the landfill site acted as the repository of unique group of cold active bacteria most of which showed potential of producing multiple enzymes.The study presents a platform for further scientific investigation through microbial profiling of landfill site that may lead to discovery of some novel microbes of high enzyme producing potential of scientific importance.
Background and Objective: The discharge of dye-contaminated wastewater into receiving water bodies culminates in several health and environmental damages.The objective of this study was to investigate the effect of nitrogen source on decolouration rate of bromothymol blue, crystal violet and methylene blue by immobilized cells of Pseudomonas aeruginosa and Bacillus subtilis. Materials and Methods:The study was carried out under batch experimental setup made of five different nitrogen sources (casein, sodium nitrate, sodium nitrite, tryptone and urea) used at respective concentrations of 5 g LG 1 .Results: In all the experimental batches, decolouration of the dyes in presence of the test bacterial cells showed progressive increase with time of incubation irrespective of the nitrogen source and the dye investigated.In presence of the Bacillus subtilis cells, highest decolouration rates of 59.83% (bromothymol blue), 70.19% (crystal violet) and 26.48% (methylene blue) were observed in media containing casein, sodium nitrate and sodium nitrite, respectively.In Pseudomonas aeruginosa inoculated cells, highest decolouration rate was observed for the bromothymol blue in media that contained the sodium nitrate.In presence of the Pseudomonas aeruginosa cells, only minute decolouration of the crystal violet and methylene blue was observed in media containing the respective nitrogen sources.Conclusion: It could thus be concluded that an appropriate nitrogen source is vital for effective microbial decolouration of the test dyes.
Background and Objective: Urban areas have become more vulnerable to flooding due to decreased imperviousness in cities and more severe rain events.Sewer modelling is used to examine urban drainage systems and their performance in case of severe rain.Accurate data for impervious surfaces is a key input factor to obtain valuable models.In this study, the use of data acquired automatically by remote sensing techniques is investigated as an alternative to other electronic databases and is manually interpreted to obtain information on the surface conditions.Materials and Methods: The study is carried out in a neighbourhood of Copenhagen and the sewer system is modelled by the commercial software MIKE URBAN 2014.Airborne images with 20 cm resolution and 4-band orthophotos were analyzed by following an object-oriented approach and used as input for calculating the percent imperviousness.Results: The results show that different types of impervious areas are determined with different accuracy.Road area coverage is underestimated, building coverage is classified accurately and the area of other impervious surfaces is over estimated.When applying the achieved classification and using this to determine the imperviousness, the sewer system is accurately modelled despite the inaccuracies in the area coverage.Conclusion: This study validates the automatic classification of areas using airborne images.The methodology, however, should be optimized with respect to road surfaces and some specific pervious surfaces.
Background and Objective: In view of scarcity of water resources due to huge amount of wastewater generated from population increase and industrialization, it has become a challenge to protect and conserve these water resources through proper treatment driven reuse.The present study was aimed at assessing the effectiveness of some natural and synthetic-adsorbent for eutrophication control by phosphate-P and nitrate-N removal from wastewater so that the resulting water can be safely reused for various economic-drivenactivities. Materials and Methods: Phosphate-P and nitrate-N removal potentials from municipal-wastewater of some natural (fly-ash, coarse-sand and cattle-dung-cake-ash and their mixture-combination) and synthetic (Ferrosorp, ferric-hydroxide, activated -alumina and their mixture-combination) adsorbents were tested in batch-experiment for 10 days at room temperature (30EC).Ten gram of each adsorbent was added to 500 mL of wastewater in battery jar.Different parameters (pH, phosphate-P, nitrate-N and available-P) were monitored using the standard protocol.Desorption of saturated Ferrosorp was also examined using different extractants.The fertilizer value of spent adsorbent (Ferrosorp) was tested for the growth of Bengal gram (Cicer arietinum) in pot.Results: Synthetic-adsorbents (activated-alumina, Ferrosorp and ferric-hydroxide) removed 92-93% phosphate-P, whereas both synthetic and natural (fly-ash, coarse-sand and cattle-dung-cake-ash) removed 100% NO 3 -N from wastewater within 10 days of contact time.The nutrient removal capacity of the test adsorbents was correlated with their porosity and surface area.Cattle-dung-cake-ash and fly-ash were also good adsorbents for removal of NO 3 -N.Though the amount of phosphate-P adsorbed by water with saturated Ferrosorp was relatively less (47.58%) than other extractants (75.50%), the spent Ferrosorp with soil revealed a pronounced effect on growth of Cicer arietinum. Conclusion:It is reasonable to conclude that Ferrosorp would be a low-cost and environmentally-sound sorbent for the treatment of phosphorous contaminated effluents and generated spent Ferrosorp could be used as potential fertilizer for enhancing crop-production.
Background and Objective: Groundwater is one of the most important renewable resources which play a great role into livelihood, economies and agriculture sector in a nation.However, this valuable resource has been defected through various ways.This study aimed to investigate the effect of over exploitation of groundwater on Barind Tract area and its probable impact on the environment.The effect of groundwater fluctuation due to deep tubewells installed in the study area for irrigation has also been investigated.The study area was Chapai Nawabganj district in Barind Tract area which is located in North-western part of Bangladesh.Materials and Methods: The study area consisted of five upazilas namely Nawabganj, Shibganj, Nachole, Gomastapur and Bholahat.Results: The experimental data were analyzed and the result revealed that the minimum water level depletion recorded was about 6.33 m below the surface at Shibgonj Upazila in 2008 and maximum water level depletion recorded was about 109.40 m below the surface at Nachol upazila in 2014.A 10-year rainfall data of the said district showed that the maximum annual rainfall recorded was 2029 mm in 2007 and since then rainfall was gradually decreased.The highest annual rainfall received in the area was 1793 mm in 2007 and the lowest was 1025 mm in 2010 in the district.The average rainfall received in Chapai Nawabganj district was 1372 mm during 2007-2016.A good trend of water table fluctuations of Chapai Nawabganj district was found during 2007-2016.Conclusion: From the analysis results, a good relation between rainfall and water table fluctuations can be observed where the groundwater table was possibly recharged through the rainfall.The overall yearly water table declining trend indicates that the unsustainable withdrawal of groundwater for irrigation purposes played a vital role in groundwater table depletion in the study area.Moreover, groundwater level fluctuation depended on the extraction and recharge of the area.
Background and Objective: Forest changes and fragmentation are the major phenomena in the tropical forest.The current study evaluated the status of this phenomenon and their impact in the Hazaribagh Wildlife Sanctuary (HWS), Jharkhand, India from 1992-2017.Materials and Methods: Four-time frame data collections, i.e., 1992, 2005,2010 and 2017 were used from the Landsat satellite sensor.Forest cover change and fragmentation measured by Forest Canopy Density (FCD) and Ritterʼs model.Forest fragmentation contains a proportion of six spatial patterns, i.e., core, transitional, interior perforated, edge and patches.The scatter plot with its regression analysis and chart diagram was the statistical procedure for calculating spectral indices correlation and forest change in the spatiotemporal framework.Results: The very dense forest and moderately dense forest declined to 12 and 20 km 2 in 2017 compared to the year 1992.The overall increase in open forest in 2017 was 15 km 2 as equate to the year 1992.The core area in the forest was increased in 2017 due to good management practices inside the forest compared to 1992 but in decreasing trend compared to the year 2005.It puts serious concern that fragmentation continue in the future and affects biodiversity.Forest fragmentation doesnʼt have much effect in the transitional forest and perforated forest balanced or less shifting of forest to non-forest and vice-versa.The interior forest acts as a protective layer of core forest from the edges.The edge of the forest has decreased, showing good sign due to minimization of the edge effect.Conclusion: The FCD and Fragmentation model combines to provides useful insight on understanding forest changing environment and future trend analysis.These types of forest modeling technique aim for effective monitoring of forest to understand the cause of forest disturbance and further help in its mitigation.
Background and Objective: Nowhere has that situation been more complex and challenging than in Egypt, where combinations of water pollution and scarcity are the most important factors impacting on water safety in Egypt.Water pollution by cyanides is an issue threatening water safety and pose a huge risk to both human and animal health.This study aimed to determine the possibility of the existence of cyanide as a critical chemical contaminant in different water sources at Assiut, Egypt.Materials and Methods: Concentrations of free cyanidein98 water samples collected from the surface, drinking, irrigation and waste waters have been evaluated by Lovibond Multi direct Photometer.Results: The results showed that cyanide level in wastewater (0.2195±0.027 mg LG 1 ) was significantly higher than surface water (0.037±0.017 mg LG 1 ), irrigation water (0.016±0.009 mg LG 1 ) and drinking water (0.016±0.004 mg LG 1 ) (p<0.05).Moreover, cyanide levels in wastewater were found to be above the maximum permissible limit imposed by USEPA and WHO.The mean pH values of the different tested water samples were 7.6738±0.05007 in drinking water 7.7543±0.15602 in irrigation water, 7.6214±0.05570 in surface water and 4.4450±0.04500 in wastewater samples.Statistically, in positive water samples for cyanide, a robust significant negative correlation between pH value and free cyanide values were recorded.Conclusion: The presence of cyanide in 54.08% of the collected water samples and a higher concentration in waste waters exceeding the permissible limits is a real threat to the health of all living organisms, especially humans and animals.Therefore, the regular estimation of cyanide in different water sources and in biological materials that allow the assessment of risks resulting from environmental exposure to such hazard pollutant is highly recommended.
Background and Objective: Microbial remediation of agriculture and natural water resources polluted by hexavalent chromium, a hazardous heavy metal pollutant by bioaugmentation with strains from extremophilic environments is an useful strategy for the xenobiotic remediation.This study reported the isolation of environmental friendly Bacillus and Pseudomonas species from a soil sample from the Mt Bromo, Indonesia volcano rim, capable of bioreducing up to 500 µg mLG 1 Cr(VI).Materials and Methods: In this study, Bacillus RB1, RB2 and RB3 and Pseudomonas RB4 sp., isolated from volcanic rim sample of Mt Bromo, East Java, Indonesia were analyzed for Cr(VI) tolerance, bioreduction using the diphenylcarbazide assay, antibiotic sensitivity, biofilm formation and functional seed germination bioassay with Vigna radiata.Results: The isolates were characterized to be Cr(VI) tolerant (upto 2 mg mLG 1 ); halotolerant (upto 6% w/v), antibiotic sensitive and strong biofilm formers in the presence of Cr(VI).All the isolates were capable of reducing 500 µg mLG 1 Cr(VI) by upto 66%.Pseudomonas RB4 also enhance seed germination of Vigna radiata by 70% in comparison to uninoculated Cr(VI) treated control.Conclusion: Microbial isolates from Mt Bromo, Indonesia volcanic rim sample were characterized to be hardy and capable of tolerating toxic Cr(VI) concentrations as well as possessing Cr(VI) reducing abilities.Such isolates from extreme environments are promising candidates to be developed as bioremediation strains for Cr(VI) polluting effluent treatments as they would be capable of surviving in harsh in field environments for successful and effective bioremediation strategies.
