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481.
482.
The performance of Vicia faba L. in soil amended by different concentrations of fly ash has been studied. The parameters considered are seed germination, growth behaviour and nodulation frequency of the plant. Results revealed that while fly-ash amendment to the soil improved the growth performance at initial stages with application of lower concentrations, it was inhibitory at higher exposure concentrations. Although there was no difference in survival rates, but the seedling growth was reduced in comparison to control plants. Fly ash delayed the nodulation as lesser number of nodules was recorded at higher amendments. Results suggested feasibility of growing V. faba in fly ash contaminated area.  相似文献   
483.
A new trematode, collected in 1971 from Ratnagiri, India, is described as Follicovitellosum indicum sp. nov. A new subfamily, Follicovitellotrematinae is created within the family Zoogonidae Odhner, 1911, to receive the new genus Follicovitellosum, with its genotype F. indicum. The new species is characterized by the follicularized nature of its ovary; the ovarian follicles are posttesticular. The vitellarium is further divided into several follicles which are largely in the pre-ovarian zone, but post-acetabular and posttesticular in location.  相似文献   
484.
The organic matter of street dust is considered as one of the causes for high human mortality rate. To understand the association, the street dust samples were collected from four different localities (industrial, residential, residential–commercial, and commercial) situated in the greater Delhi area of India. The loss-on-ignition method was used to determine the organic matter (OM) content in street dust. The OM content, potassium, calcium, sulfate, and nitrate concentrations of street dust in Delhi, India is measured to understand the spatial variation. Correlation analysis, analysis of variance, and factor analysis were performed to define the sources. The dust OM level ranges from 2.63 to 10.22 %. It is found through correlation and factor analysis that OM is primarily contributed from secondary aerosol and vehicular exhaust. The OM levels suggest that the use of a residential–commercial site for commercial purposes is polluting the street dust and creating the environmental and human health problems.  相似文献   
485.
The aquatic bodies designated as mosquito larval habitats are diverse in size and species composition. The macroinvertebrate predators in these habitats are elements that influence the abundance of mosquito species, providing a basis for biological control. Assessment of species assemblage in these habitats will indicate the possible variations in the resource exploitation and trophic interactions and, therefore, can help to frame biological control strategies more appropriately. In the present study, the species composition is being investigated in five different mosquito larval habitats at a spatial scale. A random sample of 80 each of the habitats, grouped as either small or large, was analyzed in respect to the macroinvertebrate species assemblage. The species composition in the habitats was noted to be an increasing function of habitat size (species number = 1.653 + 0.819 habitat size) and, thus, the diversity. The relative abundance of the mosquito immatures varied with the habitat, and the number of useful predator taxa was higher in the larger habitats. In the smaller habitats—plastic and earthen structures and sewage drains, the relative and absolute number of mosquito immatures per sampling unit were significantly higher than the pond and rice field habitats. This was evident in the cluster analysis where the smaller habitats were more related than the larger habitats. The principal component analysis on the species diversity yielded four and six components, respectively, for the smaller and larger habitats for explaining the observed variance of species abundance. The species composition in the habitats was consistent with the earlier findings and support that the abundance of coexisting macroinvertebrate species regulates the relative load of mosquito immatures in the habitats. The findings of this study may be further tested to deduce the relative importance of the habitats in terms of the productivity of mosquito immatures at a temporal scale.  相似文献   
486.
487.
Kinetic studies on the dechlorination of 1,1-dichloro-2,2 bis (4,-chlorophenyl) ethane (DDD) and 1,1,dichloro-2,2 bis (4,-chlorophenyl) ethylene (DDE) in 0.05% biosurfactant revealed that the reaction follows second-order kinetics. The rate of reaction was dependent on the presence of acid, initial concentrations of the target compound, and zerovalent magnesium/tetravalent palladium. Gas chromatography-mass spectrometry analyses of DDE dechlorination revealed the formation of a completely dechlorinated hydrocarbon skeleton, with diphenylethane as the end product, thereby implying the removal of all four chlorine atoms of DDE. In the case of DDD, we identified two partially dechlorinated intermediates [namely, 1,1-dichloro-2, 2 bis (phenyl) ethane and 1, chloro-2, 2 bis (phenyl) ethane] and diphenylethane as the end product. On the basis of products formed from DDD dehalogenation, we propose the removal of aryl chlorine atoms as a first step. Our investigation reveals that biosurfactant may be an attractive solubilizing agent for DDT and its residues. The magnesium/palladium system is a promising option because of its high reactivity and ability to achieve complete dechlorination of DDE and DDD.  相似文献   
488.
Aquatic biodiversity is one of the most essential characteristics of the aquatic ecosystem formaintaining its stability and a means of coping with any environmental change. The entire stretch of the Mothronwala swamp has rich riparian vegetation for providing conducive environment for the growth of aquatic organisms. The present work has been undertaken to study the bio-physico-chemical characteristics of the swamp. The data on physico-chemical environmental variables (temperature, total dissolved solutes, size and composition of substratum, pH, dissolved oxygen, alkalinity chlorides, and hardness) have been given under the present contribution. A total of 16 genera of aquatic insects belonging to orders Trichoptera, Coleoptera, Hemiptera, Ephemeroptera, Odonata and Phylum Mollusca represented the macroinvertebrates of Mothronwala swamp. The fresh water swamp of Mothronwala is under threat due to human interference and other anthropogenic activities. Some of the natural and anthropogenic environmental problems of the Mothronwala swamp have been identified and the ameliorative measures for the protection of aquatic environment and the conservation measures for the swamp have been suggested. The qualitative study revealed the present status of the aquatic biodiversity of the swamp and also about the physico-chemical parameters, which would be very helpful for policy makers to take precautionary measures to save the swamp.  相似文献   
489.
Decolourization activity of Phanerochaete chrysosporium for three synthetic dyes viz., congo red, malachite green and crystal violet and impact of additional carbon and nitrogen supply on decolourization capacity of fungus were investigated. Maximum decolourizing capacity was observed up to 15 ppm. Addition of urea as nitrogen source and glucose as carbon source significantly enhanced decolourizing capacity (up to 87%) of fungus. In all the cases, both colour and COD were reduced more in non-sterilized treatments as compared to sterilized ones. Significant reductions in COD content of dye solutions (79-84%) were recorded by fungus supplied with additional carbon and nitrogen. A highly significant correlation (r = 0.78, p < 0.001) between colour and COD of dye solutions was recorded. Thus, a readily available carbon and nitrogen source is imperative to enhance the bioremediation activity of this fungus which has been the most suitable for synthetic dyes and textile industry wastewater treatment.  相似文献   
490.
ABSTRACT: Operation of a storage‐based reservoir modifies the downstream flow usually to a value higher than that of natural flow in dry season. This could be important for irrigation, water supply, or power production as it is like an additional downstream benefit without any additional investment. This study addresses the operation of two proposed reservoirs and the downstream flow augmentation at an irrigation project located at the outlet of the Gandaki River basin in Nepal. The optimal operating policies of the reservoirs were determined using a Stochastic Dynamic Programming (SDP) model considering the maximization of power production. The modified flows downstream of the reservoirs were simulated by a simulation model using the optimal operating policy (for power maximization) and a synthetic long‐term inflow series. Comparing the existing flow (flow in river without reservoir operation) and the modified flow (flow after reservoir operation) at the irrigation project, the additional amount of flow was calculated. The reliability analysis indicated that the supply of irrigation could be increased by 25 to 100 percent of the existing supply over the dry season (January to April) with a reliability of more than 80 percent.  相似文献   
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