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Effect of Humic Acid Fertilizer on Mercury Release from Greenhouse Soils Texto completo
2024
Z. Zhao, L. Y. Long, H. Gu and R. G. Sun
The elemental mercury (Hg0) release characteristics from the Hg-contaminated soil applied with Humic acid fertilizer (HAF) in the greenhouse were identified. The adsorption features of mercuric ion (Hg2+) on HAF under different reaction times and pH were investigated to elucidate the influencing mechanism of HAF on soil Hg0 release. Besides, the microstructure of HAF loading with Hg2+ was characterized by using Fourier transform infrared spectroscopy (FTIR) and scanning electron micrograph-energy dispersive spectrometry–EDS). The results showed that with the increasing HAF dosage, soil oxidation-reduction potential (Eh), and organic matter (SOM) content, as well as the decreasing soil pH, the soil Hg0 release fluxes showed a decreasing tendency. The soil pH, Eh, SOM, and total Hg content are the key factors that can affect the soil Hg0 release fluxes. The interior air temperature, light intensity, soil moisture, and soil temperature have little impact on soil Hg0 release fluxes when the greenhouse soil is applied with HAF. The HAF can immobilize Hg2+ and reduce its activity by surface precipitation and specific adsorption, then affecting the soil Hg0 release fluxes. The results of this study provide a basis for the application of HAF to reduce soil Hg0 release fluxes in the greenhouse of Hg-contaminated areas.
Mostrar más [+] Menos [-]A Short-Term Autoregressive Model for the Prediction of Daily Average NO2 Concentration in Nagercoil, Tamil Nadu, India Texto completo
2024
P. Muthukrishnan and R. Krishna Sharma
Nitrogen dioxide (NO2) is one of the pollutants that can cause potential damage to the ecosystem. NO2 emitted from vehicles forms the primary precursor for ground-level ozone. In this study, an analysis of the daily average of NO2 concentration with meteorology measured for two years 2021 and 2022 is being carried out. It is evident from the analysis that NO2 concentration followed an apparent diurnal pattern with a maximum value in the morning hours and a minimum during the afternoon hours. Summer months recorded the highest, and North East Monsoon (NEM) recorded the lowest values of NO2. A statistically significant positive correlation was found between NO2 and Temperature. An autoregressive model was formulated to forecast the daily average values of NO2 concentration. Unit root test was performed to check the stationarity of the data points, which is important in determining trends and seasonal changes. From the model procedure, the order that best fits the data was identified as AR (4), in which the process has the current value based on the previous three values. The Akaike Information Criterion (AIC) and Schwartz Criterion (SC), which are estimators of prediction error for AR (4), are low. The Jarque confirmed the normal distribution-Bera test, which again approves the satisfactoriness of the model.
Mostrar más [+] Menos [-]Application of Arc-SWAT Model for Water Budgeting and Water Resource Planning at the Yeralwadi Catchment of Khatav, India Texto completo
2024
R. S. Sabale, S. S. Bobade, B. Venkatesh and M. K. Jose
Every facet of life, including human habitation, economic development, food security, etc., depends on water as a valuable resource. Due to the burgeoning population and rapid urbanization, water availability needs to be simulated and measured using hydrologic models and trustworthy data. To fulfill this aim, the SWAT model was processed in this work. The SWAT model was formulated to estimate the hydrological parameters of Yeralwadi using meteorological data from IMD (India Meteorological Department) for the period 1995-2020. The observed discharge data was collected from the HDUG Nasik group and used in the calibration and validation of the Model. The SWAT model was corrected & validated through the SUFI-II algorithm in SWAT-CUP to get a better result. The model’s sensitivity is checked by using statistical parameters like Nash-Sutcliffe Efficiency (NSE) and a coefficient of determination (R2). NSE values were 0.72 and 0.80 in calibration and validation, and R2 were 0.80 & 0.76 in calibration and validation, respectively, indicating the acceptance of the model. Results show that 40.6% of the total yearly precipitation was lost by evapotranspiration. The estimated total discharge from the Yeralwadi catchment was 55.6%, out of which 41.2% was surface runoff and 14.4% was baseflow. The other 17.8% was made up of percolation into confined and unconfined aquifers, which served as soil and groundwater storages. The surface runoff is influenced by Curve number (CnII), SOL_AWC, ESCO, and base flow was influenced by ALPHA-BF and GW_REVAP. This study will be useful to water managers and researchers to develop sustainable water resource management and to alleviate the water scarcity issues in the study basin.
Mostrar más [+] Menos [-]Mapping and Quantifying Integrated Land Degradation Status of Goa Using Geostatistical Approach and Remote Sensing Data Texto completo
2024
V. G. Prabhu Gaonkar, F. M. Nadaf and Vikas Kapale
Globally, land degradation is becoming a grave concern. Over the years, conditions such as drought, extreme weather events, pollution, changes in land use land cover, and desertification have intensified and led to land degradation, affecting both ecological and economic processes. Equally, during the last two centuries, population and urbanization have amplified manifold and increased the demand for additional food and shelter, resulting in alteration in land use land cover, over-grazing, and over-cultivation, loss of nutrient-rich surface soil, greater runoff from the more impermeable subsoil, and reduced water availability. Geographically, Goa is a highly diversified state. It is sandwiched between the West Coast and the Western Ghats. The state is blessed with beaches, mangroves, backwaters, wetlands, wildlife sanctuaries, evergreen forests, barren lands, and other vital ecosystems. The State of Goa, on average, receives more than 3000 millimeters of rainfall annually with high surface runoff. Using both primary and secondary data, this study sought to investigate and quantify the state’s land degradation. Secondary data came from satellites and other sources, while primary data came from field observation and ground truthing. Land degradation factors related to soil loss and the spatial pattern of soil erosion are predicted and evaluated using the Revised Universal Soil Loss Equation (RUSLE) method. Landsat-8 OLI-TIRS images were utilized to decide land use and cover (C factor), while DEM information was utilized to assess (LS factor). A soil map and rainfall data were collected to acquire a better understanding of soil erodibility (K factor) and rainfall erosivity (R factor). The kriging interpolation technique was used to gain a deeper comprehension of land degradation.The purpose of this paper is to comprehend the concept of integrated land degradation and how it affects the environment of Goa. Using remote sensing data and geostatistical methods, the study creates a comprehensive map of land degradation in the region by identifying and analyzing the various forms of land degradation in Goa. The paper also looks at how rainfall and the amount of land cover affect the rate of soil erosion in Goa. According to the findings, intense rainfall makes the eastern part of Goa particularly susceptible to soil erosion, and bare soil has a greater potential for erosion than vegetated land. The paper concludes that comprehensive land degradation mapping can be a useful tool for developing efficient land management strategies to preserve soil and encourage sustainable development in the region.
Mostrar más [+] Menos [-]Exploring the Trend of Aerosol Optical Depth and its Implication on Urban Air Quality Using Multi-spectral Satellite Data During the Period from 2009 to 2020 over Dire Dawa, Ethiopia Texto completo
2024
Teshager Argaw Endale, Gelana Amente Raba, Kassahun Ture Beketie and Gudina Legese Feyisa
This study focuses on atmospheric aerosols, especially aerosol optical depth (AOD), over Dire Dawa, Ethiopia, from 2009 to 2020. At first, a correlation between the four satellite sensors and AERONET was made for validation purposes and to determine the sensor that best represents Dire Dawa. Intercomparisons were also made among the four satellite sensors. After all statistical tests, annual, seasonal, and decadal trend analyses were made. The validation results indicated that the AOD of MODIS-terra showed the best correlation with AERONET with R2 (0.78), RMSE (0.03), and MBE of 0.02 and represented the area better than the rest. The inter-comparison of AOD retrieved from multi-spectral satellite sensors showed a positive and satisfactory correlation between MODIS-Terra and OMI. Only MODIS-Aqua showed a linearly increasing mean annual AOD with R2 = 0.43. In three seasons (summer, autumn, and spring), AOD showed linear increments over the 12 years, with R2 ranging between 0.3 and 0.5. The three seasons also had nearly identical AODs of 0.23-0.28. However, winter had the lowest value of 0.2. MODIS-terra, out of the four sensors, exhibited increasing decadal tendency over the 2009-2020 period. Monthly analysis revealed that August had the highest AOD (0.265), and January had the lowest (0.14). The value of AOD obtained from this study over Dire Dawa shows a higher value during all seasons except during winter. Thus, this study gives a glimpse into the use of multi-spectral satellite sensors to monitor air quality over a semi-arid urban region.
Mostrar más [+] Menos [-]Wetland Ecosystem: Plant Species Diversity, Services, Degradation Drivers, and Community Perception in Sinana District, Oromia Region, Southeast Ethiopia Texto completo
2024
Kemalo Abdulmalik Boru, Lalit Tukaram Ingale and Kassahun Mulatu Lemt
Wetlands are a vital source of biodiversity and ecosystem services. The study investigated the plant species diversity and assessed the perception of the ecosystem services of the area and drivers of wetland degradation in Sinana district, Southeast Ethiopia. Vegetation inventory, household surveys, focused group discussions, and key informant interviews were employed to gather information. A total of 45 sample plots laid along transacts were inventoried. A plot size of 5 m × 5 m (25 m2) and 1 m × 1 m (1 m2) nested within the major plot was used for shrubs and herbs, respectively. A total of 137 households were surveyed to collect socioeconomic data. The study identified 20 plant species belonging to 14 families. Family Cyperaceae was dominant within the studied wetland. The Shannon diversity (H=1.15) indicates that the wetland has low vegetation diversity with an uneven distribution (E=0.385) of vegetation. A total of 20 ecosystem services thought to be underprovisioning, regulating, and cultural services were identified. According to plaintiffs, major provision services are grazing livestock (77.4%), irrigation (76.6%), and harvesting of grass for fodder (68.6%). Important drivers of wetland degradation are a shortage of cropland (70.8%), lack of awareness (69.3%), upland land degradation (65.7%), and increasing population (62%). The main driver, a shortage of cropland, was the key driver, followed by a lack of awareness and upland land degradation. Therefore, the result heightened that the studied wetland is under serious degradation due to high human pressure associated with population growth and climate change. Thus, an appropriate wetland management strategy must be designed.
Mostrar más [+] Menos [-]Research Progress on in-situ Remediation of Typical Heavy Metals in Petroleum Hydrocarbon-contaminated Soil Enrichment by Plants Texto completo
2024
B. Yang, Q. H. Xue, C. T. Qu, C. Lu, F. F. Liu, H. Zhang, L. T. Ma, L. Qi and Y. T. Wang
Petroleum hydrocarbon is one of the dangerous substances in the process of petroleum development, refining, processing, transportation, and production. In the related activities of the petroleum industry, the output is large, and improper treatment will cause pollution to the surrounding environment. It is an urgent problem to conduct harmless and resource treatment of petroleum hydrocarbon polluted soil. Plant enrichment, as an environmentally friendly and pollution-free technical means, has the advantages of low cost and small change to the soil environment and effectively solves the problems of excessive heavy metals in petroleum hydrocarbons through plant enrichment. In this paper, the development process of plant enrichment, remediation methods, and plant enrichment of typical heavy metals (Cd, Hg, Zn) in petroleum hydrocarbon-polluted soil were systematically introduced. Through investigation, the mechanism and influencing factors of plant enrichment of heavy metals in the presence of petroleum hydrocarbons were summarized and analyzed, and the possible development direction of plant enrichment technology in the future was prospected.
Mostrar más [+] Menos [-]Environmental Assessment Methods for Dissolution of Soil Texto completo
2024
Deepanjali Sahu, M. K. Tiwari and Arunachal Sahu
Water plays a crucial role in the environment and in the process of liquefaction, which can occur during moderate to major earthquakes and cause significant structural damage. Liquefaction is defined as the transformation of granular material from a solid state to a liquid state, a process driven by increased pore water pressure and reduced effective stress within the soil. When an earthquake strikes, the shaking causes the pore water pressure between the sand grains to rise, which in turn reduces the contact forces between the grains. As a result, the sand loses its effective shear strength and starts to behave more like a fluid, leading to instability and potential collapse of structures built on such ground. Liquefaction can occur in moderate to major earthquakes, resulting in severe damage to structures. The transformation of granular material from a solid state to a liquid state due to increased pore pressure and reduced effective stress is defined as liquefaction. When this happens, the sand grains lose their effective shear strength and will behave more like a fluid. This phenomenon of dissolution of soil damages trees’ stability and disturbs the formation of the earth’s surface. Liquefaction resistance of soil depends on the initial state of soil to the state corresponding to failure. The liquefaction resistance can be evaluated based on tests on laboratory and in situ tests. For this research, liquefaction resistance using in-field tests based on SPT N values is attempted. Cyclic resistance ratio (CRR) is found based on the corrected N value. About 16 bore logs have been selected for the factor of safety calculation. The factor of safety for soil was arrived at by taking into account of corresponding corrected SPT N values. The liquefaction hazard map is prepared for the moment magnitude of 7.5-7.6 M w. It is also found that the areas close to water bodies and streams have the factor of safety less than unity. The bore log of locations having a factor of safety less than one indicates that up to a depth of about 6 m, very loose silty sand with clay and sand is present, which are defined as medium to fine sand having low field N values.
Mostrar más [+] Menos [-]The Impact of Iron Oxide Nanoparticles on Crude Oil Biodegradation with Bacterial Consortium Texto completo
2024
Suganya Kalaiarasu, K. J. Sharmila, Santhiya Jayakumar, Sreekumar Palanikumar and Priya Chokkalingam
This study was performed to determine the effect of synthesized iron oxide nanoparticles on the consortium of isolated bacterial strains from the crude oil-contaminated site. The iron oxide nanoparticle (FeNPs) was synthesized by chemical co-precipitation method and confirmed with its characterization results such as UV-spectroscopy, X-ray Diffraction (XRD), High-Resolution Scanning Electron Microscopy (HR-SEM), Zeta potential and Particle Size Analyser studies. The isolates were cultured in LBBH (Luria-Bertani and Bushnell Haas) medium containing crude oil as a carbon source with incubation for 7 days. This study was performed using FeNPs with four different concentrations (10, 50, 100 and 150mg) incorporated with the isolated microbes clubbed as a consortium. The rate of biodegradation was investigated by gas chromatography-mass spectrometry (GC-MS) analysis. By comparing the control sample (crude oil) there was a better degradation in FeNPs added bacterial culture than consortium degradation. The obtained results conclude that studying different concentrations of FeNPs with the consortium of isolated microbes showed degradation differences, whereas 150mg concentration has a better degradation effect compared to other variations. It should be carried out to avoid agglomeration of nanoparticles by improving their biocompatibility and quality to influence the biodegradation of crude oil.
Mostrar más [+] Menos [-]Green Marketing Practices and Sustainability Performance of Manufacturing Firms: Evidence from Emerging Markets Texto completo
2024
Derrick Nukunu Akude, John Kwame Akuma, Emmanuel Addai Kwaning and Kojo Agyekum Asiama
This study investigates the relationship between green marketing practices and the sustainability performance of manufacturing firms in emerging markets. A self-administered questionnaire was used to collect data from 270 respondents, and the analysis was conducted using Smart PLS-SEM (version 4). The results demonstrate a significant positive relationship between green internal marketing and the overall sustainability performance of the firms. Specifically, green marketing communication was found to positively influence both environmental and social performance, although it did not have a significant effect on financial performance. Likewise, the adoption of green products substantially improved environmental performance but did not significantly impact financial or social performance. Additionally, the study supports a positive association between green strategy implementation and sustainability performance. These findings underscore the critical role of integrating green marketing practices into sustainability initiatives. The research provides valuable insights for managers and policymakers, emphasizing the need for a holistic approach to green marketing to enhance environmental and social outcomes, even if financial benefits are not immediately apparent. This study contributes to the growing body of knowledge on sustainable business practices and offers practical implications for achieving long-term sustainability in manufacturing firms.
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