خيارات البحث
النتائج 341 - 350 من 575
Vulnerability of Mangroves to Changing Coastal Regulation Zone: A Case Study of Mandovi and Zuari Rivers of Goa النص الكامل
2023
T. V. Deshpande and P. Kerkar
Goa is a coastal State located on the west coast of India, known for its pristine sandy beaches and environment. Ministry of Environment and Forest implemented Coastal Regulation Zone Notification in 1991 for monitoring the coastal zones for unplanned developmental activities but has been just for name-sake purposes (Mascarenhas 1999, Agarwal 2019). The regulation has been changed in recent years thereby making the coastal and the riverine ecosystem more vulnerable to human interference. In the name of development, various hap-hazardous, unplanned activities have taken place which is degrading the coastal and riverine environment, especially mangroves. This paper studies the vulnerability of mangroves to the changing regulations with respect to 1991 and the 2018 CRZ notifications considering the land use land cover changes in the regulated zones of Mandovi and Zuari rivers. Spatial analysis techniques and software such as Arc GIS 10.3, and ERDAS IMAGINE 2014 have been used for analysis and results. The findings from the study can be effectively implemented in monitoring the regulated zones and protecting mangroves efficiently.
اظهر المزيد [+] اقل [-]Analysis of Water Quality of Hatirjheel Lake, Dhaka, Bangladesh النص الكامل
2023
A. B. M. Kamal Pasha, Syed Omayer Mustafa, S. M. Mahmudur Rahman, Muhammad Abdullah, Md. Azharul Haque Chowdhury and Mahfuza Parveen
The study assessed the status of water quality parameters for an urban water body (Hatirjheel Lake) in Dhaka, the Capital city of Bangladesh. Nine different water samples were collected from nine points of the lake during the dry season in January 2021. Water quality parameters such as pH, electrical conductivity (EC), total dissolved solids (TDS), total suspended solids (TSS), total alkalinity, total acidity, total hardness, Ca2+ hardness, free CO2, and dissolved oxygen (DO) were determined for the samples. The status of the parameters is pH (6.51-7.05), EC (510-600 μS.cm-1), TDS (450-590 ppm), TSS (0.0-0.034 mg.L-1), total alkalinity (80-392 mg.L-1), total acidity (224-500 mg.L-1), total hardness (348-452 mg.L-1), Ca2+ hardness (74-162 mg.L-1), free CO2 (730-1170 mg.L-1), DO (2.7-5.5 mg.L-1). However, the DO value at some points of the lake is too less (2.7 mg.L-1 and 3.7 mg.L-1) than the standard value (> 5-6 mg.L-1) of ECR, DoE, which might not be healthy for any water body and aquatic ecosystem. Other water quality parameters are within the permissible limit of WHO and ECR, DoE.
اظهر المزيد [+] اقل [-]Identification and Characterization of Aluminium Tolerant Bacteria Isolated from Soil Contaminated by Electroplating and Automobile Waste النص الكامل
2023
H. Bisht and N. Kumar
Due to anthropogenic activities and the advancement of industries, metal contamination is growing globally. Aluminum toxicity is seriously endangering plants, animals, and humans by rapidly rising in soil and water. Even though some fungi can tolerate aluminum, researchers are interested in finding bacteria that are resistant to aluminum. The current state of knowledge on bacteria resistant to aluminum is extremely limited. In the present study, bacterial isolates from soil near a metal electroplating and automobile industry in Punjab, India, were isolated and then screened for high aluminum metal tolerance. The aluminum tolerant bacterial isolate was identified as Cedecea davisae M1, a member of the Enterobacteriaceae family, using morphological, biochemical, and 16srRNA gene sequence analyses. The spectroscopic results indicate that the strain may tolerate up to 150 ppm of aluminum. Antibiotic resistance of Cedecea davisae M1 was determined using disks on Luria agar plates, and the bacteria were found to be resistant to vancomycin, ampicillin, carbenicillin, and rifampicin. The findings of the study indicated that the strain might be able to remove aluminum toxicity from the environment, which needs to be further explored.
اظهر المزيد [+] اقل [-]Improved Large-Scale Ocean Wave Dynamics Remote Monitoring Based on Big Data Analytics and Reanalyzed Remote Sensing النص الكامل
2023
Subhrangshu Adhikary and Saikat Banerjee
Oceans and large water bodies have the potential to generate a large amount of green and renewable energy by harvesting the ocean surface properties like wind waves and tidal waves using Wave Energy Converter (WEC) devices. Although the oceans have this potential, very little ocean energy is harvested because of improper planning and implementation challenges. Besides this, monitoring ocean waves is of immense importance as several ocean-related calamities could be prevented. Also, the ocean serves as the maritime transportation route. Therefore, a need exists for remote and continuous monitoring of ocean waves and preparing strategies for different situations. Remote sensing technology could be utilized for a large scale low-cost opportunity for monitoring entire ocean bodies and extracting several important ocean surface features like wave height, wave time period, and drift velocities that can be used to estimate the ideal locations for power generation and find locations for turbulent waters so that maritime transportation hazards could be prevented. To process this large volume of data, Big Data Analytics techniques have been used to distribute the workload to worker nodes, facilitating a fast calculation of the reanalyzed remote sensing data. The experiment was conducted on Indian Coastline. The findings from the experiment show that a total of 1.86 GWh energy can be harvested from the ocean waves of the Indian Coastline, and locations of turbulent waters can be predicted in real-time to optimize maritime transportation routes.
اظهر المزيد [+] اقل [-]Water Quality Assessment of Wenyu River with Variable Weight Cloud Model النص الكامل
2023
Li Guojiao, Men Baohui and Wang Lehao
The water resource is an important guarantee of social and economic sustainable development. The improvement of water’s ecological carbon sequestration ability is a direct response to the goal of “double carbon”. Water quality directly affects its carbon sequestration capacity. So it is necessary to understand the water quality of rivers. In view of the fuzziness and uncertainty in water quality evaluation, this paper uses the cloud model to realize the qualitative to quantitative transformation of water quality in Wenyu River. By combining moment estimation theory with critic weight, AHM weight, and variable weight theory. A water quality evaluation method integrating a variable weight cloud model is constructed. And the temporal and spatial changes in water quality in Wenyu River are studied. The results show that the combined weights balance the influence of each index while retaining the advantages of subjective and objective weights. The results of the water quality evaluation are consistent with the practice, which verifies the feasibility and applicability of the method.
اظهر المزيد [+] اقل [-]Corrosion Behavior of Petroleum Pipeline Steel in the Sulfur Ion Enriched Solution with Quinoline النص الكامل
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.
اظهر المزيد [+] اقل [-]Evaluation of the Energy Factor and Equivalent CO2 Gas Emission by Utilization of Industrial By-products in Concrete for Environmental Protection النص الكامل
2023
B. Saravanan, R. Divahar, S. P. Sangeetha and M. Bhuvaneshwari
Climate change and global warming are two of the world’s most pressing environmental issues. With CO2 being one of the most significant greenhouse gases released into the atmosphere, and cement and concrete manufacturing accounting for roughly 10% of worldwide CO2 emissions, the construction sector must employ an environmentally sustainable substance as a substitute for cement. The CO2 emissions, energy factor, and strength qualities of concrete were investigated. Those negative reaction of conventional cementitious substances is reduced by the development of binary and ternary cementitious systems. In this study, two mineral admixtures obtained from industrial waste substances, red mud (RM) and silica fume (SF), had been used as the alternatives for cement and fine aggregate was fully replaced by manufactured sand (M-sand). An experimental examination of the compressive strength, water absorption, density of concrete, equivalent CO2 emission, and energy factor for environmental benefits with the comparison of RM on SF-based eco-friendly concrete mix of M30 grade was used. A binary and ternary blended cementitious system with RM and SM was created with twelve various mix proportions, varying from 0-20% by 5% increases. From the binary blended cementitious system (BBS), based on the observed mechanical characteristic of concrete it was found that the optimum level of RM was 15% and SF was 10 % by the volume of cement. Similarly, for the ternary blended cementitious system (TBS), the level of 10% RM and 10% SF in the cement mixture provides a much higher improvement in compression strength compared to the alternative trials. The negative sign implies that replacing cement with RM and SF reduces energy consumption (-1.91% to -6.97%) and CO2 emissions (-4.52% to -16.16%). The use of mineral admixtures such as RM and SM in supplementary cementitious materials results in a significant outcome and potential impact on the production of sustainable concrete that addresses environmental issues.
اظهر المزيد [+] اقل [-]Evapotranspiration Over the Indian Region: Implications of Climate Change and Land Use/Land Cover Change النص الكامل
2023
Garima Singh and Sudhir Kumar Singh
Evapotranspiration (ET) plays a significant role in climatic studies, directly influencing the hydrological cycle, energy balance equation, and surface vegetation. ET comprises three components: bare soil or ground evaporation, evaporation, and transpiration, in which vegetation removes water influenced by food grain production. In turn, soil moisture availability depends on precipitation characteristics over land, surface net radiation, and wind speed are the major climatic factors that together determine the magnitude of ET. This controls moisture availability in the lower troposphere, hence atmospheric stability, chances of cloud formation, and precipitation. Though the study of evapotranspiration is important for determining agricultural water consumption and analyzing drought situations, there is a lot of uncertainty in its accurate estimation. Land use/Land cover changes (LULCC) occurring throughout the Indian subcontinent have been found to affect the characteristics of low to moderate rainfall events and surface temperature extremes (Halder et al. 2016). A global warming scenario will change the hydrological cycle, and the impact of anthropogenic factors has also necessitated the need to understand the mechanisms that control changes in ET over India. In this study, we want to analyze the relationship between transpiration and the Normalized Difference Vegetation Index (NDVI) and investigate the relationship between canopy interception with respect to NDVI all over the Indian region. Attempts have been made to assess the impact of changes in climate and LULC on ET and its three components over the Indian region from 1981 till the present time. The monsoon season increases precipitation, and soil evaporation is found to increase at first, along with an increase in NDVI followed by canopy evaporation and transpiration. It is noted that changes in precipitation and LULCC across the Indian subcontinent have contributed significantly to changes in ET in different seasons. As variability in surface net radiation also plays an important role in controlling changes in total ET, it is being investigated.
اظهر المزيد [+] اقل [-]Assessment of Particulate and Gaseous Fluoride in Phosphate Fertilizer Industry النص الكامل
2023
S. Jawahar, K. Shridhar, V. Dhananjayan, K. Panjakumar, B. Ravichandran, A. Ravinder Nath and Nirmala Babu Rao
Fluorides are emitted in both gaseous and particle forms in the industrial sector. However, studies usually only report total fluoride content. Therefore, the study aimed to assess the particulate, gaseous fluoride and correlate it with the respirable dust particles in Single Super Phosphate (SSP), Granular Single Super Phosphate (GSSP), and administration divisions of the industry. Respirable dust particles, particulate fluoride, and hydrogen fluoride in the work environment were collected on a filter cassette containing an MCE filter paper (0.8 micron 37-mm) and Na2CO3 impregnated backup pad, respectively, using a personal sampler. The fluoride samples were analyzed using Ion Selective Electrode (ISE) and expressed as milligrams per meter cube (mg.m-3). The respirable dust, particulate, and gaseous fluoride content were found to have statistically significant differences (p<0.001) between the divisions (SSP, GSSP, and administration) in the static monitoring, whereas, in the case of personal monitoring, no significant differences were observed. Average airborne respirable, particulate, and gaseous fluoride levels in static monitoring were 1.37, 1.03, 0.20 mg.m-3, 0.018, 0.008, 0.001 mg.m-3, and 0.808, 0.403, 0.026 ppm in SSP, GSSP and administration respectively, whereas in personal monitoring the average respirable, particulate and gaseous fluoride concentrations were 1.18, 0.85, 0.30 mg.m-3, 0.0013, 0.007, 0.002 mg.m-3 and 0.356, 0.258, 0.011 ppm in SSP, GSSP and administration respectively. The present study observed that the levels of fluoride decreased with an increase in distance from SSP, followed by GSSP and administration. It indicates that the fluoride exposure was inversely proportional to the distance of the source. This study outcome will help to design a policy and intervention to mitigate fluoride exposure among workers.
اظهر المزيد [+] اقل [-]Impact of Nanoplastics on Marine Life: A Review النص الكامل
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.
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