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Assessment and Prediction of Air Quality Level Using ARIMA Model: A Case Study of Surat City, Gujarat State, India
2023
H. N. Mahendra, S. Mallikarjunaswamy, D. Mahesh Kumar, Shilpi Kumari, Shubhali Kashyap, Sapna Fulwani and Aishee Chatterjee
Air quality has recently been a huge concern as it directly affects people’s lives. An air quality level assessment and prediction system is essential to keep track of air quality. Therefore, developing an efficient air quality assessment and prediction system has become one of the most important concerns. In the present work air quality level of Surat city, India is assessed and predicted for the period from 2020 to 2023 using the Autoregressive integrated moving average (ARIMA) model. Experimental results show that the ARIMA model outperforms the other models. According to the findings, the maximum quantity of SO2 and NO2 present in the air in 2020 is 37 mm and 18 mm, respectively, with a maximum of 27 mm and 31 mm in 2021. Thus, we can observe that even though SO2 has reduced a bit, the amount of NO2 has increased, thus degrading the quality of air.
Show more [+] Less [-]Retention Behaviour of Heavy Metals from Industrial Sludge Amended with Admixtures to Use Them as Liners for Landfill Facilities
2023
S. S. S. Saranya, S. N. Maya Naik and Shankara
The solidification of contaminants within the soil/waste has proved to be a versatile technique to de-contaminate them and make them usable for several applications. In this method, the development of binder provisions leads to the conversion of the environmentally unstable condition of waste materials into a nearly stable material. Further, these materials pose a minimum threat that can be absorbed into the environment. Normally lime/cement and other pozzolanic materials are used as binder materials. In this work, it is proposed to use the efficiency of binding fly ash to improve the unconfined compressive strength (UCC) of soils, particularly during the curing period. This is because improvement in strength is a reflection of the improvement of bonding soil particles. Fly ash as the main source material, in addition to a minor proportion of cement and lime, is used to determine the strength. UCC test results revealed that as the percentage of fly ash increases there is an increase in compressive strength. It is also observed that with an increase in lime content and an increase in cement content, the UCC strength also increases. The strength in cement-stabilized compacted specimens is more compared to lime-stabilized mixtures. To confirm that the improvement in strength is related to the solidification of contaminated metals, particularly for soils containing copper and chromium, the stabilized mixture is tested for the leaching of these metals. Leaching tests were conducted on various stabilized mixtures at different curing periods. The leachate was examined for metal ion concentration using Atomic Absorption Spectrophotometer. The leaching behavior of heavy metals from different proportions of soil matrix revealed that with an increase in lime or cement percentage, a decrease in leachability is observed. It is found that the leaching of heavy metals from cement-stabilized soils was lower than in lime mixture combinations. However, minimum strength improves the solidification and retention of heavy metals effectively.
Show more [+] Less [-]Variability and Trend in Summer Monsoon Rainfall and its Correlation with Crop Yield in the Districts of Andhra Pradesh During 2011-2020
2023
Chandu Kavitha , A. Dharma Raju and S.V.J. Kumar
In the context of climate change and its impact on agriculture, the paper analyses the trend of monsoon rainfall and its correlation with crop yield in Andhra Pradesh. The summer monsoon is the main rainy source of water for the state of Andhra Pradesh. The Kharif crops depend on the southwest monsoon rains to the extent that its adverse variability may lead to water stress and agrarian crisis. It has been observed from the study that in recent years the contribution of monsoon rainfall during September is increasing, and any harvest during the month is correspondingly affected, leading to a decline in the crop yield.
Show more [+] Less [-]Corrosion Behavior of Petroleum Pipeline Steel in the Sulfur Ion Enriched Solution with Quinoline
2023
Shanjian Li, Guotao Cui, Panfeng Wu and Yang Feng
Localized corrosion is a serious, hazardous destroyer of steel petroleum pipelines meant for long-time use. However, previous studies on localized corrosion primarily focused on local corrosion morphology and corrosion rate of bulk metals because detecting the corrosion state of occlusive metals is difficult. Herein, we employ a simulating occluded battery unit to disclose the local corrosion behavior of the steel petroleum pipeline (N80 steel) in an occlusive S2–-enriched solution. After simulating localized corrosion in the S2–- containing corrosion solution using the occluded battery unit, the occlusive solution was acidified and the migration amount of S2– to the occluded area increased. Despite the increase of S2– concentration, the addition of quinoline corrosion inhibitor (0.8 wt%) still effectively impedes the corrosion of the occluded metal. Moderately raising the environmental temperature can stimulate the activity of the inhibitor and promote the inhibition effect. The quinoline corrosion inhibitor displays the maximum inhibition rate at an elevated temperature of 50°C. Meanwhile, a maximum over the temperature of 60°C-70°C will likely accelerate the failure of the inhibitor.
Show more [+] Less [-]Groundwater Quality Assessment in Korba Coalfield Region, India: An Integrated Approach of GIS and Heavy Metal Pollution Index (HPI) Model
2023
Vijayendra Pratap Dheeraj, C. S. Singh, Nawal Kishore and Ashwani Kumar Sonkar
The goal of this study was to examine the water quality for drinking and domestic purposes in the Korba coalfield region of Chhattisgarh, India. The Korba Coalfield region has seen the collection of fifteen groundwater samples from different places. The content of eight metals was determined using ICP-MS instruments: aluminum (Al), barium (Ba), cadmium (Cd), iron (Fe), magnesium (Mn), lead (Pb), nickel (Ni), and zinc (Zn). Spatial distribution maps were produced using GIS software to make it simple to understand the groundwater’s quality. The groundwater samples were collected during the pre-monsoon season and the amount of Al, Ba, Cd, Fe, Mn, Pb, Ni, and Zn exceeded the ideal drinking water standards in a few sites. The elevated metal concentrations in the study region’s groundwater could be hazardous to the quality of water. The HPI value based on mean concentration was calculated to be 21.64, which is significantly lower than the reference pollutant index score of 100. The HPI calculation revealed that 73.33% of groundwater samples had low HPI values, 6.67% had medium HPI values, and the remaining 20% had high HPI values. The correlation between heavy metals and HPI was calculated; HPI is positively correlated with Fe (r > 0.9471), Pb (r > 0.9666), and Zn (r > 0.9634), indicating that these elements contribute significantly more to heavy metal concentration in the various samples examined than the other selected elements. The box plot seems to be a graphical representation of the outcomes of the different parameter concentrations which show the mean, maximum, and minimum metal values. The cluster analysis was performed and it was classified into two clusters. Cluster-1 comprises 14 members (93.33%) of the water samples examined and is distinguished by relatively low Ba (<700 μg.L-1), pH, TDS, Al, Fe, Cd, Mn, Pb, and Zn concentrations. Cluster-II is made up of 1 member (6.67%), which is primarily made up of groundwater samples (GW-10) taken in the KCF region, India. High values of HPI are found in the eastern portion of Chhattisgarh’s KCF region, reflecting the spatial distribution of metals. Heavy metal leaching from open-pit mining and transit routes was observed to have contaminated groundwater in the eastern section of the research region.
Show more [+] Less [-]Spatial Distribution of PM10 and NO2 in Ambient Air Quality in Cape Town CBD, South Africa
2023
O. Ndletyana, B. S. Madonsela and T. Maphanga
Fixed air quality monitoring stations generally monitor the air quality in developing countries. However, this practice, in addition to being costly, inherently contains drawbacks associated with the inability to capture the spatial distribution of air pollutants. Against this limitation, it is necessary to employ flexible and dynamic monitoring techniques that are fundamental and influential in comprehending the spatial distribution of pollutants. Because of this, in recent times, the application of GIS as a monitoring technique has proved to be more efficient than using fixed monitoring stations. Therefore, to this end, the current study mapped the spatial distribution of PM10 and NO2 pollutants in Cape Town CBD using the GIS technique. Subsequently, the GIS monitoring technique revealed that both pollutants had high spatial distribution between 2017 and 2018, irrespective of the season. Furthermore, high exposure concentrations of PM10 were generally observed across the CBD in contrast to NO2 exposure levels, which were relatively low. To contextualize the findings, compared with other studies, the current research discovered that spatial distribution of air pollution is associated with meteorological conditions, such as wind speed and temperature, that traditional techniques of monitoring exposure can’t capture.
Show more [+] Less [-]Amsterdam urban water system as entry point of river plastic pollution
2023
Tasseron, Paolo | Begemann, Finn | Joosse, Nonna | van der Ploeg, Martine | van Driel, Joppe | van Emmerik, Tim
Accumulation of plastic litter in aquatic environments negatively impacts ecosystems and human livelihood. Urban areas are assumed to be the main source of plastic pollution in these environments because of high anthropogenic activity. Yet, the drivers of plastic emissions, abundance, and retention within these systems and subsequent transport to river systems are poorly understood. In this study, we demonstrate that urban water systems function as major contributors to river plastic pollution, and explore the potential driving factors contributing to the transport dynamics. Monthly visual counting of floating litter at six outlets of the Amsterdam water system results in an estimated 2.7 million items entering the closely connected IJ river annually, ranking it among the most polluting systems measured in the Netherlands and Europe. Subsequent analyses of environmental drivers (including rainfall, sunlight, wind speed, and tidal regimes) and litter flux showed very weak and insignificant correlations (r = - 0.19–0.16), implying additional investigation of potential drivers is required. High-frequency observations at various locations within the urban water system and advanced monitoring using novel technologies could be explored to harmonize and automate monitoring. Once litter type and abundance are well-defined with a clear origin, communication of the results with local communities and stakeholders could help co-develop solutions and stimulate behavioral change geared to reduce plastic pollution in urban environments.
Show more [+] Less [-]Differential effects of arsenite and arsenate on rice (Oryza sativa) plants differing in glutathione S-transferase gene expression
2023
Pandey, Ambika | Wu, Lin-Bo | Murugaiyan, Varunseelan | Schaaf, Gabriel | Ali, Jauhar | Frei, Michael
Contamination of paddy soils with arsenic (As) can cause phytotoxicity in rice and increase the accumulation of arsenic in grains. The uptake and accumulation of As in rice depends on the different As species present in the soil. Plants detoxify As by conjugating and sequestering xenobiotic compounds into vacuoles using various enzymes. However, the severity of damage induced by arsenite (As(III)) and arsenate (As(V)), as well as the roles of glutathione S-transferase in detoxifying these As species in rice, are not fully understood. In this study, we developed plant materials overexpressing a glutathione S-transferase gene OsGSTU40 under the control of the maize UBIL promoter. Through systematic investigations of both wild-type Nipponbare (Oryza sativa L., ssp. japonica) and OsGSTU40 overexpression lines under chronic or acute stress of As, we aimed to understand the toxic effects of both As(III) and As(V) on rice plants at the vegetative growth stage. We hypothesized that (i) As(III) and As(V) have different toxic effects on rice plants and (ii) OsGSTU40 played positive roles in As toxicity tolerance. Our results showed that As(III) was more detrimental to plant growth than As(V) in terms of plant growth, biomass, and lipid peroxidation in both chronic and acute exposure. Furthermore, overexpression of OsGSTU40 led to better plant growth even though uptake of As(V), but not As(III), into shoots was enhanced in transgenic plants. In acute As(III) stress, transgenic plants exhibited a lower level of lipid peroxidation than wild-type plants. The element composition of plants was dominated by the different As stress treatments rather than by the genotype, while the As concentration was negatively correlated with phosphorus and silicon. Overall, our findings suggest that As(III) is more toxic to plants than As(V) and that glutathione S-transferase OsGSTU40 differentially affects plant reactions and tolerance to different species of arsenic.
Show more [+] Less [-]Impact of Nanoplastics on Marine Life: A Review
2023
S. Das
Minute plastic subdivisions like microplastics and nanoplastics have recently gained considerable attention because of their toxic effects on the environment and human health. Many plastics have been consumed worldwide regularly, and most are thrown away after a single use. They all end up in the sea and ocean, leading to a large debris of plastic garbage in the marine environment. Different physical and chemical processes occur in the marine ecosystem to degrade the macroplastics into micro- and nano-level plastics. Owing to their small size and large surface area, nanoplastics can easily be ingested into the tissues and organs of various marine species (both vertebrates and invertebrates) and accumulate more toxic materials in them than micro and macroplastics. Several reports have been obtained on the toxicity of plastics and microplastics on marine organisms. Still, till now, a cursory report has been found on the potential risk of nanoplastics in connection with marine life. This review highlights the origins of nanoplastics (NPs), their properties, characterization, and impact on marine ecosystems, along with their remediation and future aspects. The review will also untangle and specify the area of nanoplastics on which further research is urgently needed to better understand its toxic effect and eco-friendly restoration on the environment, especially on marine life.
Show more [+] Less [-]Effect of Fulvic Acid on the Denitrification in Deep Subsurface Wastewater Infiltration System
2023
Jingjing Lv, Jingjing Li, Yanyan Dou, Guoke Chen, Yubing Ye and Li’an Hou
This work aims to explore the impact of fulvic acid (FA) on denitrification within the purification process of sewage in the deep subsurface wastewater infiltration system (DSWIS). In the system, an organic glass column (height = 2.40 m; radius = 0.30 m) was filled with several layers of soil. Simulated domestic wastewater and extracted FA from landfill leachate were used in the experiments. It was found that before and after the addition of FA, COD, and NH4+-N were efficiently removed when a hydraulic load was 8 cm·d-1. Moreover, after FA addition, the removal efficiency of TN was enhanced from 67.74% to 78.01%. Organic matter transformation analysis indicated that in the under part, the shortage of carbon sources limited the denitrification prior to FA addition, resulting in a low TN removal efficiency. However, after adding FA, more FA-like substances were transferred into protein-like matters than before the addition of FA, which has helped produce more easily biodegradable organics for denitrification. So, the addition of FA could enhance the denitrification process in the system of DSWIS.
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