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61.
To meet the growing energy demand worldwide, oil and gas exploration and production activities have increased rapidly both in onshore and offshore areas. The produced oil from the ocean bed is transported onshore either by ship or pipeline. This has increased the risk of oil spill in the coastal area. In order to prepare an emergency preparedness plan and to assess the magnitude of risk involved in transporting and offloading oil, oil spill simulation studies play an important role. This paper describes a simulation of oil spill in coastal bay of Arabian Gulf where new developments are taking place using MIKE 21 model. The developments include a diesel based thermal power plant near Sir Baniyas Island, which is an ecological fragile area. Based on the project activity, two probable scenarios, one for diesel leak (250 m3/h) for 1 h and the other for instantaneous spill (500 m3) are considered. The MIKE 21 model was calibrated for hydrodynamics using measured field data followed by diesel-spill simulation to track its movement in the Arabian Gulf. The results for both leak and instantaneous spill indicate that spilled diesel will not move towards the Sir Banyas Island and more than 45% of the diesel will be evaporated within 48 h of oil spill. Based on the results, a clean up and contingency plan is proposed to mitigate the adverse impacts arising due to diesel spill in the study area.  相似文献   
62.
Environmental Science and Pollution Research - This study investigates the effect of environmental risk factors among North Indian children aged between 6 and 16 years associated with body mass...  相似文献   
63.
Environmental Science and Pollution Research - The present work aims to investigate seasonal variations in air pollution levels in Lucknow and assess the ambient air quality of the city together...  相似文献   
64.
The levels of cadmium (Cd), chromium (Cr), and copper (Cu) were assessed in 24 fruit species in Meerut, North India using atomic absorption spectrometry. Data showed that Cd concentrations in fruits except banana, pomegranate, papaya, orange, and cherry were above the recommended maximum allowable limit of Food and Agriculture Organization (FAO)/World Health Organization (WHO) (0.2 µg/g). Average Cr concentrations in all analyzed fruit samples were also found higher than the safe limit of FAO/WHO (2.3 µg/g). In contrast, fruits viz. banana, lychees, papaya, Indian apple, Asian apple, and tiger nut showed concentration of Cu below the recommended safe limit (40 µg/g). Our study demonstrated that concentration of studied heavy metals in all tested samples varied according to fruit species and respective contaminants. Data suggest that more strict rules/standards need to be applied by National/International regulatory agencies in order to make these important fruit items free from heavy metals contamination and protect the consumer.  相似文献   
65.
66.
Allelopathic effect ofAvena fatua L., Cyperus rotundus L., Polygonum hydropiper L., and Solanum nigrum L. were examined on seedling growth of certain commonly used varieties of wheat (Triticum aestivum L.) in the Tarai region of U.P. state. The weed extracts inhibited the length of plumule in all the varieties (100%) with Solanum and it was in 12 (92%), 10 (77%) and 06 (46%) varieties with Polygonum, Avena and Cyperus, respectively. In radicle length, it was in 92% with both Polygonum and Solanum; and 85% and 69% of the varieties with Avena and Cyperus, respectively. However, all the four weed extracts reduced the dry weight of plumule, radicle and total seedling in all the varieties (100%) of wheat except in HD--2329 with Cyperus, in which it was positive. The percent reduction (percentage of control) was more than 50% in 92%, 77%, 54% and 39% of the varieties, respectively with Solanum, Polygonum, Avena and Cyperus. Among the weed extracts, the inhibitory effect on seedling growth in different varieties followed the order: Solanum > Polygonum > Avena and > Cyperus. On the basis of the present results, UP--2003 and WH--542 followed by PBW--226, Sangam and HD--248 were more susceptible to all the four weed extracts compared to the rest of the varieties of wheat.  相似文献   
67.
The development of methods and strategies to reduce the emission of methane from paddy fields is a central component of ongoing efforts to protect the Earth's atmosphere and to avert a possible climate change. It appears from this investigation that there can be more than one strategy to contain methane emission from paddy fields, which are thought to be a major source of methane emission in tropical Asia. Promising among the mitigating options may be water management, organic amendments, fertilizer application and selection of rice cultivars. It is always better to adopt multi-pronged strategies to contain CH4 efflux from rice wetlands. Use of fermented manures with low C/N ratio, application of sulfate-containing chemical fertilizers, selection of low CH4 emitting rice cultivars, and implementation of one or two short aeration periods before the heading stage can be effective options to minimize CH4 emission from paddy fields. Among these strategies, water management, which appears to be the best cost-effective and eco-friendly way for methane mitigation, is only possible when excess water is available for reflooding after short soil drying at the right timing and stage. However, in tropical Asia, rice fields are naturally flooded during the monsoonal rainy season and fully controlled drainage is often impossible. In such situation, water deficits during the vegetative and reproductive stage may drastically affect the rice yields. Thus, care must be taken to mitigate methane emission without affecting rice yields.  相似文献   
68.
Biochemical toxicity of benzene   总被引:7,自引:0,他引:7  
Human exposure to benzene in work environment is a global occupational health problem. After inhalation or absorption, benzene targets organs viz. liver, kidney, lung, heart and brain etc. It is metabolized mainly in the liver by cytochrome P450 multifunctional oxygenase system. Benzene causes haematotoxicity through its phenolic metabolites that act in concert to produce DNA strand breaks, chromosomal damage, sister chromatid exchange, inhibition of topoisomerase II and damage to mitotic spindle. The carcinogenic and myelotoxic effects of benzene are associated with free radical formation either as benzene metabolites or lipid peroxidation products. Benzene oxide and phenol have been considered as proheptons. Liver microsomes play an important role in biotransformation of benzene whereas in kidney, it produces degenerative intracellular changes. Cohort studies made in different countries suggest that benzene induces multiple myeloma in petrochemical workers. Though extensive studies have been performed on its toxicity, endocrinal disruption caused by benzene remains poorly known. Transgenic cytochrome P450 IIE1 mice may help in understanding further toxic manifestations of benzene.  相似文献   
69.
A study of temporal variation in methane efflux from the rice-fields indicated that weeds could modulate the CH4 emission by transporting atmospheric O2 more efficiently than rice plants to the rhizosphere, which suppressed CH4 formation in the oxic condition, inhibiting methanogenic activity. A more oxic environment in the sediment was reflected by the higher redox potential in the weed growing plots. Besides, cultivar differences in methane efflux might be attributed to various plant activities, more importantly root exudation, development of aerenchyma and the biomass. Peak emission of CH4 at the flowering stage in all the rice cultivars was associated with maximum extension of root mat, releasing exudates, which serve as carbon source for the methanogenic bacteria for CH4 formation.  相似文献   
70.
Environment, Development and Sustainability - Weather variability over the long run exhibits the trends of change in climate and forewarns for development and deployment of adaptation measures....  相似文献   
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