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951.
Anjil Kumar Srivastava Ravi Ranjan Kumar Ashok Kumar Singh 《Environmental science and pollution research international》2014,21(24):13979-13986
Municipal solid wastes (MSW) are unavoidable sources of environmental pollution. Improper disposal of municipal waste results in the leaching of toxic metals and organic chemicals, which can contaminate the surface and ground water leading to serious health hazard. In this study, the toxic effects of the leachate prepared from municipal solid waste samples were examined in root meristem cells of barley (Hordeum vulgare L.) at various stages of cell cycle, i.e., G1, S, and G2. Seeds of barley were exposed to 2.5, 5, and 10 % of leachates in soil and aqueous media in 48 h at different cell cycle stages. The physicochemical data of the present study revealed that municipal solid waste leachate contains high amount of heavy metals, which significantly affected growth and physiological activities of barley. Significant inhibition in hypocotyl length, germination, and mitotic index were observed at all concentration of leachate treatment. Induction of chromosomal aberrations (CA’s) and micronuclei (MN) formation were also observed with different concentrations of leachate treatment at 7, 17, and 27 h of presoaking durations, which falls in G1, S, and G2 phase of the cell cycle, respectively. Also, exposure of leachate at S phase of the cell cycle had significant effects in barley through chromosomal aberration and micronuclei formation. 相似文献
952.
Robert Paine Carlos Szembek David Heinold Eladio Knipping Naresh Kumar 《Journal of the Air & Waste Management Association (1995)》2014,64(12):1390-1402
Emissions of pollutants such as SO2 and NOx from external combustion sources can vary widely depending on fuel sulfur content, load, and transient conditions such as startup, shutdown, and maintenance/malfunction. While monitoring will automatically reflect variability from both emissions and meteorological influences, dispersion modeling has been typically conducted with a single constant peak emission rate. To respond to the need to account for emissions variability in addressing probabilistic 1-hr ambient air quality standards for SO2 and NO2, we have developed a statistical technique, the Emissions Variability Processor (EMVAP), which can account for emissions variability in dispersion modeling through Monte Carlo sampling from a specified frequency distribution of emission rates. Based upon initial AERMOD modeling of from 1 to 5 years of actual meteorological conditions, EMVAP is used as a postprocessor to AERMOD to simulate hundreds or even thousands of years of concentration predictions. This procedure uses emissions varied hourly with a Monte Carlo sampling process that is based upon the user-specified emissions distribution, from which a probabilistic estimate can be obtained of the controlling concentration. EMVAP can also accommodate an advanced Tier 2 NO2 modeling technique that uses a varying ambient ratio method approach to determine the fraction of total oxides of nitrogen that are in the form of nitrogen dioxide. For the case of the 1-hr National Ambient Air Quality Standards (NAAQS, established for SO2 and NO2), a “critical value” can be defined as the highest hourly emission rate that would be simulated to satisfy the standard using air dispersion models assuming constant emissions throughout the simulation. The critical value can be used as the starting point for a procedure like EMVAP that evaluates the impact of emissions variability and uses this information to determine an appropriate value to use for a longer term (e.g., 30-day) average emission rate that would still provide protection for the NAAQS under consideration. This paper reports on the design of EMVAP and its evaluation on several field databases that demonstrate that EMVAP produces a suitably modest overestimation of design concentrations. We also provide an example of an EMVAP application that involves a case in which a new emission limitation needs to be considered for a hypothetical emission unit that has infrequent higher-than-normal SO2 emissions.
ImplicationsEmissions of pollutants from combustion sources can vary widely depending on fuel sulfur content, load, and transient conditions such as startup and shutdown. While monitoring will automatically reflect this variability on measured concentrations, dispersion modeling is typically conducted with a single peak emission rate assumed to occur continuously. To realistically account for emissions variability in addressing probabilistic 1-hr ambient air quality standards for SO2 and NO2, the authors have developed a statistical technique, the Emissions Variability Processor (EMVAP), which can account for emissions variability in dispersion modeling through Monte Carlo sampling from a specified frequency distribution of emission rates. 相似文献
953.
Wazir Singh Lakra Uttam Kumar Sarkar Rupali Sani Kumar Ajay Pandey Vineet Kumar Dubey Om Prakash Gusain 《The Environmentalist》2010,30(4):306-319
In the present communication habitat ecology, species diversity; distribution and different indices of fish biodiversity management
were studied in a Central India river (River Betwa, a tributary of River Ganga basin approved under India’s first river linking
plan). Correlation between fish species richness with the hydrological attributes showed good relationship and water depth,
dissolved oxygen and pH were found the most important variables in shaping fish assemblage. Altogether, sixty-three fish species
belonging to 20 families and 45 genera were collected from five sampling stations spread along the upstream, mid stream and
lower streams. Cyprinids were the most dominated group represented by 26 species belonging to 15 genera, followed by Bagridae
(6 species from 3 genera), and Schilbeidae (4 species from 4 genera). The distribution of fish showed interesting pattern
and about 10% species were common to all the sites showing long migration range. Shannon-Weiner diversity index showed considerable
variation and ranged from 1.89 to 3.51. Out of 63 species status of 10 species were not known due to data deficit, 29 categorized
as lower risk, 14 as vulnerable, 8 as endangered, while the remaining two species were introduced. Our study shows that the
River supports considerable diversity of the fishes and is important for conservation and about 34% fish fauna is threatened
being either vulnerable or endangered. We assessed that the river supports considerable percentage of food fish (89.47), ornamental
fish (49.12%) and sport fish (5.26%). Among the eight major types of fish habitats identified along the entire stretch of
river, open river, shallow water and deep pools were habitats contributing maximum diversity. Fish species richness (FSR)
were significantly different (P < 0.05) in all the habitats except channel confluence and scour pool. Trophic niche model may be useful for assessing altered
as well as less altered fish habitat of the tropical rivers. Since this river will be interlinked in near future, this study
would be useful for conservation planning and management and also for future assessment after interlinking. Issues related
to various threats to aquatic environment and conservation management strategies have been discussed. 相似文献
954.
955.
Jaya Kumar S Naik KA Ramanamurthy MV Ilangovan D Gowthaman R Jena BK 《Journal of environmental management》2008,89(1):35-44
The 26th December 2004 Indian Ocean tsunami devastated coastal regions of the Indian subcontinent. Andaman and Nicobar Islands, coastal stretches of Tamil Nadu, Andhra Pradesh and Kerala were the most affected regions of India. Changes in the beach profiles, long shore currents, breaking wave characteristics in the surf zone at selected locations along the Tamil Nadu coast were studied during January, April, October 2005 and January 2006. Long shore sediment transport rates were estimated from the observed parameters. Studies were carried out earlier (1995-1996 and 1998) to understand the coastal environment over a one-year cycle in the study region. The post-tsunami observations were compared with the earlier studies to establish the variations in the littoral environment and to ascertain the normalcy of the littoral environment in the post-tsunami scenario. From the changes in the beach profiles, the shoreline was observed to recede by about 20m and built-up of backshore by about 0.5m at most locations. Observations from the field investigations and comparisons with earlier studies along this stretch of the coastline indicate that the coastline is yet to return completely to normalcy. 相似文献
956.
This paper provides baseline information about the total annual dust fall, and its constituents and seasonal variation, from a sub-tropical opencast coalmine area in Bina, India. Dust samples were collected monthly for 2 years (June 2002-May 2004) from five sampling sites in the region and analyzed in the laboratory for water-soluble and -insoluble matter. Water-insoluble components constituted the major fraction of the total annual dust fall. Two-way ANOVA indicated significant variations in dust fall at different sites, over the months and in their interactions. The dust deposition rate was highest during summer (March-June), followed by winter (November-February) and lowest in the rainy season (July-October). Maximum dust fall was observed near the coal handling plant (at site 2) followed by the receiving pit of the coal handling plant (site 3), near the main sub-station (site 4), Jawahar colony (site 1) and Gharasari village (site 5). An inverse and significant relation was observed between dust fall and precipitation. Our studies have shown that the main residential areas are experiencing higher levels of dust fall which makes them unsuitable for living. We suggest that residential areas should be moved farther away from the mining area in the opposite direction of prevalent winds. 相似文献
957.
Jinal Hardik Naik Gopi Kachhadiya Kumar Krishna Amaresan Natarajan 《Environmental science and pollution research international》2021,28(6):6540-6548
Environmental Science and Pollution Research - Soil contamination by heavy metals is one of the major abiotic stresses that cause retarded plant growth and low productivity. Among the heavy metals,... 相似文献
958.
Verma Anushka Giri Arun Kumar Debata Byomakesh 《Environmental science and pollution research international》2023,30(6):14518-14532
Environmental Science and Pollution Research - This study intends to examine the impact of ICT diffusion, globalization, financial development, government effectiveness, and economic growth on... 相似文献
959.
Hussain Mahamed Sahed Mostafa Mazarbhuiya Agnimitra Biswas Kaushal Kumar Sharma 《International Journal of Green Energy》2020,17(2):171-179
ABSTRACTVertical axis wind turbine (VAWT) is an economic and widely used energy converter for converting wind energy into useful form of energy, like mechanical and electrical energy. For efficient energy conversion in low wind speed and to have improved power coefficient of asymmetric blade VAWT, selection of optimum blade thickness is needed thus entailing its detailed investigation with respect to different operating wind speed conditions. Present study methodically explores the impact of thickness to chord (t/c) ratio on aerodynamic performance of a three bladed asymmetrical blade H-Darrieus VAWT at different low wind speed conditions by using 2D unsteady CFD simulations. The optimal t/c is obtained on the basis of maximum power coefficient and average moment coefficient of the turbine. The aerodynamic performance curves are obtained at different operating and t/c conditions and the performance insights are corroborated with the findings from the flow physics study to come to some concrete conclusions on the effects of the thickness to chord ratio. The present study identifies large blade curvature to create a large diverging passage on the blade suction surface as the prominent reason for aerodynamic performance drop at a high t/c ratio. 相似文献
960.
R. Srinivas Ajit Pratap Singh Ayush Aman Gupta Piyush Kumar 《Environmental monitoring and assessment》2018,190(12):720
Global scarcity of freshwater has been gearing towards an unsustainable river basin management and corresponding services to the humans. It needs a holistic approach, which exclusively focuses on effective river water quality monitoring and quantification and identification of pollutant sources, in order to address the issue of sustainability. These days, rivers are heavily contaminated due to the presence of organic and metallic pollutants released from several anthropogenic sources, such as industrial effluents, domestic sewage, and agricultural runoff. It is astonishing to note that even in many developing countries, most of these contaminants are carried through open drains, which enter river premises without proper treatment. Such practice not only devastates riverine ecosystem but also gives rise to deadly diseases, such as minimata and cancer in humans. Considering these issues, the present study develops a novel approach towards simultaneous identification of major sources of pollution in the rivers, along with critical pollutants and locations using an advanced hierarchical cluster and multivariate statistical analysis. A systematic approach has been developed by agglomerating both R-mode and Q-mode analysis, which develops monoplots, two-dimensional biplots, rotated component matrices, and dendrograms (using “SPSS” and “Analyse It” software) to reveal relationships among various quality parameters to identify the pollutant sources along with clustering of critical sampling sites and pollutants. A case study of the Ganges River Basin of India has been considered to demonstrate the efficacy and usefulness of the model by analyzing 85 open drains. Both organic and metallic pollutants are analyzed simultaneously as well as separately to get a holistic understanding of all the relationships and to broaden the perspective of water characterization. Results provide a comprehensive guidance to the policy makers and water managers to optimize corrective efforts, minimize further damage, and improve the water quality condition to ensure sustainable development of the river basin. 相似文献