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Exploring the Nexus Between Urban Land Use/Land Cover (LULC) Changes and Urban Growth Analysis Using Geoinformatics in Tumkur City, India
2024
A. Kishor Kumar, Govindaraju, C. J. Rakesh and S. Lokanath
For the past several decades, Tumkur has been one of the fastest-developing cities in Karnataka. Hence, an assessment concerning the identification of LULC mutations and their intensity and urban sprawl in Tumkur City has been employed using cutting-edge Geospatial techniques. In this study, multi-temporal satellite imagery such as Landsat 5 (2000), Resourcesat-1 (2005, 2009 & 2012), and Sentinel-2A (2015 & 2020) were utilized to monitor historical LULC changes, land transformation, direction of urban growth and sprawl. The outcome of the change detection demonstrates that between 2000 and 2020, the built-up area expanded significantly, from 24.94 km2 to 60.59 km2. Consequently, the land transformation matrix analysis shows that substantial modifications in LULC have occurred over the period, with a rise in built-up areas and plantations and a decline in agricultural land, water bodies, and scrubland. Further, urban expansion analysis using UEII (Urban Expansion Intensity Index) revealed that most of the area is in the fast-paced stage of urban expansion. Moreover, two well-known indices; the Annual Urban Spatial Expansion Index (AUSEI) and the Annual Built-up Change Index (ABCI), show a significant positive correlation between them (R2 = 0.69) justifying the increased urban growth in the study area. Whereas, built-up density and the Annual Urban Spatial Expansion Index (AUSEI) show a negative correlation (R2 = 0.55) indicating the presence of compactness of the core of the city. Apart from the above analysis, urban sprawl was effectively interpreted using zones formed using Shannon entropy; NNE, ESE, and SSW have high urban sprawl due to National Highways, growth of Industries, and infrastructure activities developed by the government. Further, the present study’s findings will contribute to understanding land use dynamics, urban sprawl, urban growth analysis, and future projections, as well as provide crucial information for decision-making and urban planning processes, to the urban planner to support acceptable land use management and guiding plan for appropriate growth of urban areas.
Afficher plus [+] Moins [-]Chlorella vulgaris – A Potential Biodiesel Feedstock’s Effect on the Performance, Emission and Combustion Phenomenon of a CI Engine with Hydrogen Inductance
2024
S. Pughazhraj, D. Balaji, V. Hariram, R. Kumaraswamy, J. Godwin John, P. Naveen and T. S. Ravikumar
In the modern world, the rise of industrialization and motorization has significantly increased the use of internal combustion engines powered by petroleum products. This has led to the unsustainable exploitation and depletion of petroleum reserves. Consequently, the use of biodiesel-based biofuels, particularly those derived from microorganisms, along with gaseous fuel supplementation in internal combustion engines, has gained prominence. The urgent need to explore alternative fuels for combustion engines has become evident over the past few decades due to the rapid decline in fossil fuel reserves. This study examines the impact of hydrogen induction in the throttle body of a CI engine powered by blends of biodiesel from Chlorella vulgaris and mineral diesel in various proportions, without major engine modifications. The research aims to evaluate the performance, combustion, and emission characteristics of the engine when supplemented with hydrogen, biodiesel, and their blend B20. The experiments involve varying fuel compositions and engine operational parameters to assess their influence on efficiency, pollutant emissions, and combustion stability.
Afficher plus [+] Moins [-]Bioactivity of Rhizospheric Acinetobacter baumannii Siderophore Combined with Antibiotics Against Lower Respiratory Tract Pathogenic Bacteria
2024
Rafal Moayad Abdul-Latif and Amel Hussaein Mussa
The study focused on extracting and purifying siderophore produced by Acinetobacter baumannii isolated from rhizospheric soil in Baghdad city and evaluating its bioactivity both independently and in combination with selected antibiotics. Bacterial identification was performed using CHROM agar, biochemical, and physiological tests, with confirmation via PCR amplification of the 16S rDNA housekeeping gene. The siderophore was extracted using ethyl acetate after culturing the bacteria in succinate broth and was purified through HPLC, detected at a wavelength of 403 nm. A total of 38 bacterial isolates were obtained from lower respiratory tract infections, including Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Staphylococcus aureus, and Serratia marcescens. Antibiotic susceptibility testing with 13 antibiotics showed the highest resistance rates to ampicillin (65.7%) and ceftriaxone (63.1%), while the lowest resistance was observed with amikacin (15.7%). The synergistic activity of the siderophore combined with sub-MIC concentrations of ceftriaxone, ceftazidime, and gentamycin was tested against multidrug-resistant (MDR) isolates. The most significant antibacterial activity was observed with the combination of siderophore and gentamycin against S. aureus, whereas a minimal effect was noted on A. baumannii. In conclusion, 38 bacterial isolates were successfully identified from lower respiratory tract infections. The combination of siderophore with gentamycin exhibited notable antibacterial activity against S. aureus but was ineffective against A. baumannii.
Afficher plus [+] Moins [-]A Comprehensive Review on the Role of Bioremediation in Heavy Metal Contamination
2024
Princy Rajput, Shashank Benjwal and Rohit Pandey
Heavy metal contamination, along with other pollutants, presents significant environmental hazards. These substances not only endanger human health but also disrupt natural ecosystem. Bioremediation emerges as a sustainable and economically viable approach to tackling pollution. It harnesses the capabilities of microorganisms, plants, and their enzymes to degrade or neutralize pollutants. This paper categorizes bioremediation into two primary types: ex-situ and in-situ. Ex-situ bioremediation treats contaminated material away from its original location, while in-situ bioremediation addresses contamination directly at the site. This paper also explores how microbes tolerate heavy metals through various mechanisms. These mechanisms encompass extracellular barriers, efflux pumps, enzymatic reduction, and intracellular sequestration. Extracellular barriers function to block the entry of metals into the cell, whereas efflux pumps work actively to expel metals from the cell. Enzymatic reduction facilitates the conversion of metals into less harmful forms, while intracellular sequestration involves storing metals within the cell. Moreover, the paper examines diverse applications of bioremediation in environmental restoration. These applications encompass natural attenuation, enhanced reductive dechlorination, sewage treatment, bioleaching, biosorption, constructed wetlands, biostimulation, and bioaugmentation. This paper emphasizes the need for further research to optimize bioremediation technologies for broader real-world environmental management applications.
Afficher plus [+] Moins [-]Isolation, Identification, and Characterization of Putative Dye-Degrading Bacteria from Polluted Soil: Bioremediation Investigations
2024
M. M. Sahila, M. Shonima Govindan, N. K. Shainy, P. Nubla and M. Kulandhaivel
The residual dye within the soil from the synthetic dye manufacturing and fabric industries is a global state of affairs. The discharge consists of an excessive content of pigments and other components, creating complicated structures. It leads to damage to the soil structure and its fertility. Amid existing amputation methods, microbial remediation takes significant consideration owing to its subordinate charge, sophisticated proficiency, and fewer influences on the milieu. The current study was premeditated for the seclusion and portrayal of azo dye- dye-decolorizing bacteria, which is a criterion for emerging a microorganism-facilitated treatment of adulterating dyes. In this present investigation, twenty sorts of bacteria that were talented to decolorize seven kinds of azo dyes (Crystal Violet, Methylene Blue, Safranine, Congo Red, Methyl Orange, Malachite Green, and Carbol Fuchsin) were isolated from dye-polluted soil from the dying industry near the railway station; in Calicut. Based on 16S rDNA scrutiny, the most resourceful decolourizing bacteria for these azo dyes was identified as Priestia megaterium strain NRBC 15308. After characterization, Priestia megaterium was found to be optimally nurtured at 35°C, on a pH of 7, with a 1.5% glucose concentration in a minimal salt medium. 100% decolorization of a 6% dye solution was found at optimal conditions by Priestia megaterium. Priestia megaterium can decolorize cotton and gauze suspended in the dye solution in 24 hours. Bioremediation studies with the isolate proved that the inhibition effect of the dye solution on seed germination could be removed by the application of Prestia megaterium. The isolation of Priestia megaterium strain NRBC 15308 as a dye-degrading bacterium holds immense promise for remediating dye-contaminated soil.
Afficher plus [+] Moins [-]GIS-Based Assessment of Soil Erosion Using the Revised Universal Soil Loss Equation (RUSLE) Model in Morigaon District, Assam, India
2024
Ananya Saikia, Monjit Borthakur and Bikash Jyoti Gautam
Soil erosion in the agricultural landscape of Assam has been impacting the livelihoods of millions. In administrative regions like districts, which are vulnerable to natural disasters like floods and bank erosion, GIS-based soil erosion estimating studies can help planners and policymakers identify areas of soil erosion to implement scientific conservation measures. The main purpose of this study is to estimate soil loss and to determine soil loss zones in the Morigaon district of Assam. The Revised Universal Soil Loss Equation (RUSLE) combined with GIS has been incorporated into the present study. The five parameters of RUSLE, namely, rainfall-runoff erosivity, soil erodibility, topographic factor, cover management, and conservation practices, are individually estimated from relevant and authentic data sources, and all these parameters are quantified in GIS. The research findings show that 46.89% of areas in the district are in moderate soil loss zone, eroding 0.78 ton/ha/year, 34.27% of areas are in low soil loss zone, 15.36% of areas are in high soil loss zone, eroding about 12.22 ton/ha/year and 3.47% of areas are in a very high soil loss zone, eroding 192.8 ton/ha/year. The high soil loss zones mainly cover the riverine areas and bare lands in the district. As per our estimation, there is an average of 205.85 tonnes of soil loss in the district per hectare per year.
Afficher plus [+] Moins [-]Environmental Impact of Al-Dalmaj Marsh Discharge Canal on the Main Outfall Drain River in the Eastern part of Al-Qadisiya City and Predicting the IQ-WQI with Sensitivity Analysis Using BLR
2024
Zahraa Z. Al-Janabi, Idrees A. A. Al-Bahathy, Jinan S. Al-Hassany, Rana R. Al-Ani, Ahmed Samir Naje and Afrah A. Maktoof
Monitoring water quality changes in any body of water is crucial as it directly relates to climate change. Evaluating the quality and quantity of fresh water for various uses is essential to maintaining safe water sources now and in the future. This study examined the water quality of the Main Outfall Drain River (MOD) in the eastern part of Al-Qadisiya Governorate at three sites over four seasons in 2023, using the Iraqi Water Quality Index (IQ-WQI). In most cases, the concentrations of dissolved oxygen (DO), biochemical oxygen demand (BOD5), and total dissolved solids (TDS) exceeded allowable limits for freshwater and aquatic life protection. The major contributing parameters to the river’s low water quality were TDS, BOD5, turbidity, and DO. The use of the MOD for discharging agricultural effluents led to increased levels of TDS, BOD5, and turbidity. Temporal variation indicated that the summer season had the highest values compared to other seasons due to increased evaporation and low water discharge. Spatial variation showed the IQ-WQI of the sites in descending order from very poor water to unsuitable, with Site 3 having double the TDS concentrations compared to other sites. This increase may be attributed to the impact of the Al-Dalmag Marsh discharge canal, which comes into contact with the MOD at this site. Sensitivity analysis using backward linear regression was applied to predict the IQ-WQI and determine the most influential parameters on the IQ-WQI score. The test was conducted for two sets of water parameters (from the IQ-WQI calculation) and included 7 parameters for each freshwater and aquatic life use, obtaining different models.
Afficher plus [+] Moins [-]Adoption Intention of Technology-Based Water Generation and Management Through W-TAM
2024
Rajashree Jain, Sarika Sharma, Deepthi Setlur, Aditya Bajaj and Dhwani Parekh
Increasing concerns related to climate change and extensive use of water resources have depleted the available water for use. For water as an essential requirement for humans to carry onto their day-to-day chores, access and availability of water becomes the highest priority. Technology-based solutions support water generation, filtration, quality testing, water distribution, and many other areas. The present paper dwells on the user acceptance of these technologies. A conceptual model was developed through a literature review and named as Water-Technology Acceptance Model (W-TAM). The data was collected through a self-designed survey instrument to empirically test the proposed model. Analysis of this data was done with confirmatory factor analysis and structural equation modeling. It was observed that the actual use of these technologies depends on the ease of use and usefulness. Attitude to use them also matters. Although perceived risks and affordability did affect the use of W-TAM, trust, and regulatory aspects did not confirm their role in the adaptation of W-TAM. These findings will provide meaningful insights to the stakeholders and will help them in the practical implementation of these water-based technologies. This may also help service providers in the formulation of policies for technology-based water generation.
Afficher plus [+] Moins [-]A Review on Electrooxidation Treatment of Leachate: Strategies, New Developments, and Prospective Growth
2024
R. Priyadarshini Rajesh and M. P. Saravanakumar
Improper disposal of landfill leachate, a highly polluted wastewater, can harm living beings and the ecosystem. Of all the treatment technologies available, electrochemical techniques have the most advantages in terms of ease of use, affordability, and the ability to degrade various contaminants found in landfill leachate effectively. Though there are a sufficient number of research articles regarding the electrochemical treatment of leachate, it has many research gaps, such as a study on the mechanism of radicle generation, pollutant degradation, study on different electrodes with various pollutants concentrations, application of green catalysts, byproduct formation assessment, energy recovery, etc. This review article explores the applications of electrooxidation techniques for the treatment of landfill leachate. Key aspects discussed include the (i) fundamental concepts in electrochemical treatment and its mechanism, (ii) factors affecting the electrochemical treatment efficiency, (iii) the applicability of leachate treatment with different electrochemical methods, (iv) recent advances, (v) merits, and demerits and (vi) proposal of future scope and the studies needed. The integration of electrooxidation with other treatment processes and the challenges hindering widespread adoption are also addressed. Overall, electrooxidation demonstrates promise as an effective and sustainable method for managing landfill leachate. Consequently, this article directs chacurrent and future research efforts toward optimizing the leachate treatment through electrooxidation techniques.
Afficher plus [+] Moins [-]Modeling Landslide Hazard in the Eastern Himalayan Mountain Region of the Papumpare District of Arunachal Pradesh, India Using Multicriteria Decision-Making (MCDM) and Geospatial Techniques
2024
Tilling Riming, Praduyt Dey, Santanu Kumar Patnaik and Manju Narzary
Landslides are significant natural hazards that cause damage to the environment, life, and properties, mainly in hilly terrain. This research was mostly focused on generating a landslide susceptibility zone map of Papumpare District, Arunachal Pradesh, and classifying the region from high susceptibility to least susceptibility using AHP modeling techniques considering the landslide causative factors. The Analytical Hierarchy Process (AHP) is a multicriteria decision-making model (MCDM) in which each parameter is compared based on its role in triggering a landslide. A total of eight parameters were selected based on the factors that could affect the most, like Slope, Rainfall, Drainage Density, Lineament Density, Geomorphology, Soil, Geology, and Land use/Land cover. These layers were prepared using ArcGIS 10.8 software and ERDAS IMAGINE 2014. Based on the output, the region was classified into five zones of landslide susceptibility classes. Of these, the high-very-high landslides are mostly amassed near the steep and disturbed slopes due to earth-cutting, especially for building or construction of roads. Validation was done using the ROC curve (73.2%) suggesting good performance of the model. The outcome of this work will provide information for proper landslide hazard management and will help in formulating suitable mitigation strategies in the future.
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