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71.
Analysis of Long-term Energy and Carbon Emission Scenarios for India   总被引:2,自引:1,他引:2  
In the coming years India faces greatchallenges in energy and environment. Thepath of development chosen by India, uponwhich lies the future growth of energy andemission trajectories, would be greatlyinfluenced by technological developmentsboth within and outside the country,economic cooperation between countries, andglobal cooperation in limiting greenhousegas emissions. This paper discusses theintegrated modeling system used fordeveloping and analyzing the long-termtrajectories and presents results for thescenarios developed. In the context ofongoing market reforms two scenarios –accelerated and decelerated reforms – aredeveloped depicting fast and slow progressin energy sector reforms compared toexpectations in the baseline scenario.Accelerated market reforms would spurimprovements in technological efficiencies.Reforms would lower investment risks inIndia, thereby stimulating increased levelsof foreign direct investment. On the otherhand in decelerated reform scenarioeconomic growth is lower than that in thebase case, there is low access to capital,and technological improvements lag behindthose in the base case. In another scenariowe assume specific policy interventions forpenetration of renewable technologies overthe baseline scenario, for promotion andaccelerated deployment of renewable energytechnologies over and above the baselineassumptions. A scenario with carbon(c) constraints has also been developed and theresults discussed.  相似文献   
72.
Summary We have demonstrated that females of the primitively eusocial tropical wasp Ropalidia marginata can discriminate nestmates from nonnestmates outside the context of their nests. This was accomplished by recroding all behavioural interactions in a neutral arena and comparing tolerance levels. In order for these wasps to make such a discrimination, however, it was essential that after eclosion both the discriminated and the discriminating animals were exposed to their respective natal nests and nestmates. The results suggest that both recognition labels and templates are acquired by the animals from sources outside their body, perhaps from their nest or nestmates. It is thus unlikely that different genetic lines within a colony can be distinguished. We conclude, therefore, that genetic asymmetries created by haplodiploidy, but often broken down by multiple mating and polygyny, are not restored by preferential altruism towards full rather than half sisters by means of kin recognition. Hence we recommend caution in ascribing the multiple origins of eusociality in the Hymenoptera to haplodiploidy.  相似文献   
73.
The concentrations and distribution of the elements, including heavy metals such as As, Ba, Br, Co, Cr, Cs, Fe, Ga, K, Mn, Na, Rb, Sc, Sr, Th and Zn, were investigated in dated sediment cores of Nainital Lake located in the Himalayan region, in Uttar Pradesh state of India, which is considered as a remote background area. The concentrations of the elements were measured by instrumental neutron activation analysis using the k0 method. The International Atomic Energy Agency certified reference material SL-3 was used to evaluate the accuracy of the method. The normalized data for a series of elements were used to understand the source of loading. Elements like Br, Co, Cr, Fe, K, Mn and Zn show a negative correlation with increasing depth whereas elements like As, Ba, Cs, Na and Rb show a positive correlation with increasing depth. By considering the concentration for the bottom segments of the core as close to the baseline concentration, recent flux values for different elements were calculated. An increase in the flux value was observed for Br, Cr, Fe, K, Mn and Zn, which can be attributed to anthropogenic contribution in recent years.  相似文献   
74.
A methodology is presented based on decision analysis for making decisions on environmental problems as required in the environmental impact assessment context. The major issues are identified, and the ability of the methodology to address these issues discussed. Explicit treatment of uncertainty and value tradeoffs, and the ability to consider different points of view are the important features of the methodology. Because of its sound theoretical foundation and its systematic and logical development, the methodology is well suited for documenting and justifying the decision process in public, regulatory, and judicial hearings. Case histories are summarized to illustrate the wide range of applicability of the methodology.  相似文献   
75.
Cage experiments at the discharge area of Madras Atomic Power Station (MAPS) facilitated studies of thermal tolerance in Emerita asiatica. At the laboratory, oxygen consumption at various temperatures and varying salinities was also investigated. In the field 100% mortality of crabs was recorded at the Condenser Cooling Water Pumps (CCWP) discharge site compared to no mortality at the Processed Sea Water Pumps (PSWP) site. This observation implicated temperature as a stress factor at the CCWP outfall, because other factors, including residual chlorine and water velocity, were the same at the PSWP and CCWP sites. Laboratory experiments on tolerance revealed that 38.5 degrees C was lethal to mole crabs. The time taken for 100% mortality decreased as the temperature increased from 35 to 40 degrees C. Oxygen metabolism showed a progressive increase with temperature from 29 to 36 degrees C, and declined at 37 degrees C. The influence of salinity on oxygen consumption was marginal at salinities of 20 to 35 per thousand but, when reduced to 15 per thousand, the oxygen consumption declined. The present study thus indicates that temperature could be the lethal factor, determining the distribution of mole crabs near the power station, where water temperature can exceed 40 degrees C.  相似文献   
76.
The refraction of the 2004 Indian Ocean tsunami waves caused drastic devastation along East coast of India, mainly in the area of investigation. Here, we appraise and integrate the sedimentary characteristics and microfossil studies of the area. The gigantic tsunami waves caused the landward fining of sediments that were carried as suspended load. Tsunami sediments have distinctive characteristics, like fine-to-medium grained sand, moderately to poorly sorted sediments which indicating sudden winnowing followed by tranquil flood. Positively skewed grain size distribution indicating unidirectional transport, and mesokurtic to platykurtic character implying poorly sorted single source origin. The species of benthonic foraminifers and ostracods reside in marine environment indicating shallow water origin of sediments. The onshore deposits are vertically divided into three depositional units interpreted from Ground Penetrating Radar (GPR) signatures—Unit 1 is a relatively continuous parallel layer indicative of calm environment; Unit 2 has paleochannels and burial scarps, seen as oblique reflections that might be indicative of an intense erosional environment; Unit 3 is interpreted as 2004 tsunami layer, has three subunits. Each main units have been separated by Heavy Mineral Concentrated (HMC) layers, deposited by continuous wave action (~?20 cm) and by the tsunami (>?30 cm) activity, evidenced by low magnetic susceptibility values at the bottom compared to the top of the HMC layers. GPR has been effectively utilized in this paper as subsurface imaging tool for the interpretation and reconstruction of stratigraphy, and also helped to unearth the erosional and depositional environments.  相似文献   
77.
The effects of lithium (Li) supplementation on lipid profile and fluidity of cerebrum and cerebellum membranes in aluminum (Al)-treated rats were investigated. A significant decrease in the levels of total lipids and cholesterol was observed in both the regions following Al exposure, which however were significantly increased following Li supplementation. Further, glycolipids and gangliosides contents were significantly decreased in cerebrum, but increased in cerebellum following Al treatment. Interestingly, Li supplementation reversed the trends and regulated the levels of glycolipids and gangliosides. Al treatment also elevated conjugated diene formation and phospholipid levels in both cerebrum and cerebellum membranes, which however were decreased upon Li supplementation. The cholesterol/phospholipid ratio however was decreased after Al treatment and Li supplementation was able to enhance the ratio in both cerebrum and cerebellum. Further, Al treatment significantly increased the fluorescence polarization, anisotropy and order parameter, which however were normalized following Li supplementation. The levels of Al were also found to be significantly elevated in cerebrum and cerebellum after Al treatment and normalized in cerebellum following Li treatment. Therefore, the present study shows the potential of Li in regulating the changes produced by Al on membrane composition and fluidity in rat brain.  相似文献   
78.
Ecology of fouling bryozoans in Cochin waters   总被引:3,自引:0,他引:3  
An extensive study was conducted on the settlement and seasonal succession of fouling bryozoans in and around Cochin Harbour during the period 1965 to 1966; it was the first study of its kind performed in Indian waters. A total of 14 species was recorded from localities which were ecologically dissimilar. A distinct succession of species, mainly of a seasonal character, was observed. Seasonal succession usually occurs in localities where seasons are well marked, and where different species of animals with short life spans settle during particular times of the year. The study has shown that a distinct seasonal succession of bryozoans occurs in this locality; out of the 14 species which appeared on the panels not one species settled throughout the year. This was due to seasonal differences in the ecological conditions which prevailed in the area investigated. The significant seasonal influences on the incidence of bryozoans led to a categorisation of the species into the following patterns (a) typical brackish-water forms not encountered in purely marine localities; (b) typical brackish-water forms which may occur in marine localities; (c) typical marine forms never found in localities where low salinity conditions prevail.Part of a thesis submitted by the first-named author for his degree of Doctor of Philosophy of the University of Kerala, India.  相似文献   
79.
Environmental Science and Pollution Research - Good brain health refers to a condition in which a person may fully realize their talents and improve their psychological, emotional, cognitive, and...  相似文献   
80.
The present study focuses on the determination and abundance of trace metals (viz. Cu, Ni, Zn, Cr, Co, Cd, Mn and Fe) in the surficial sediments of west coast of Arabian Sea along the Indian subcontinent. Sediment samples were collected from three transects along the western continental shelf of Arabian Sea. The enrichment of Fe and Mn in coastal oxic-sediments indicates the precipitation of these redox sensitive elements as Fe- and Mn-hydroxides and oxides, whereas the low Fe and Mn concentrations in the oxygen deficient sediments of deeper stations reflects the dissolution of their hydroxides and oxides. Concentrations of fairly redox insensitive trace metals like Cu, Ni, Zn, Cr and Cd (with the exceptions of Cr) showed higher values at nearshore sediments, then it decreased towards seaward and again showed a slight increase at oxygen minimum stations in all the three transects. This geochemical variability in their distributional characteristics is mainly associated with the extent to which the precipitation or dissolution of Fe- and Mn-oxides/hydroxides occur since the scavenging or releasing effects of Fe- and Mn-oxides/hydroxides act as significant ‘sinks’ or ‘sources’ of heavy metals. The change in wind pattern, coastal upwelling and increased productivity are also the reported factors which influence the biogeochemical cycling of trace metals in the surface sediments of west coast of India. Enrichment factor generally showed a high gradient accumulation from nearshore to shelf.  相似文献   
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