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71.
Sacred groves are well recognized in the world in terms of biodiversity conservation. The present study was conducted in the Nakuleshwar sacred grove, in the valley of Thal kedar hill in the Kumaon region of Pithoragarh district in Indian Himalaya, in appreciation of its role in biodiversity conservation. The study aimed at the documentation and inventory of the sacred grove, its phytodiversity, threats and conservation in the Himalayan region, and to achieve this, systematic field surveys were conducted during 2007?C2010 covering all four seasons. A total of 83 species from 71 genera and 50 families were identified, of which 43 species are flowering plants, including 7 trees, 7 shrubs, 4 climbers and 25 herbs, and 40 species are non-flowering plants of which lichens are represented by 12 species from 8 genera, bryophytes 6 species from 5 genera, and pteridophytes 7 species from 9 genera, while gymnosperms are represented by a single species. Acer oblongum, Cinnamomum tamala, Cedrus deodara, Coriaria nepalensis act as keystone species in the grove. Ophiopogon inermis is a common herb during the rainy season while Goodyera hemsleyana (Orchid) is a new distribution record for the western Himalaya. A total of 43 species from 38 genera are used ethnobotanically by local people for various ailments. Mahonia nepaulensis, Asparagus adscendens, Thalictrum foliolosum, Cinnamomum tamala and Berberis asiatica are highly exploited species and need to be conserved. Climatic conditions of the grove are moderate and the floristic patch of the grove is completely different from the plant diversity of the surrounding area and matches with the diversified floral wealth of comparatively higher altitudes. Due to anthropogenic pressure, this grove is facing new threats of degradation, hence needing special attention.  相似文献   
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Due to the presence of toxic metals, dumping of heavy oil fly ash (HOFA) is causing ever-growing environmental problem including the pollution of air, water and soil. The present study investigates the possible environmental impacts associated with the land disposal of HOFA generated in the power plant. Different modeling and laboratory analysis were integrated to address the real environmental problems. Leaching behavior of heavy metals within the HOFA were investigated by laboratory batch leaching tests, which confirmed that most of the toxic elements in the HOFA can easily leach into the environment with rain water. The level of atmospheric dust surrounding a HOFA dumping site was predicted using the Industrial Source Complex (ISC3) air dispersion model, and the results indicated that the dumping of HOFA could be a potential hazard for local air quality. The study also revealed different reuse options of HOFA. The characteristic analysis confirmed HOFA can be used as a natural adsorbent to remove pollutants from wastewater or as soil stabilizing material by blending with cement.  相似文献   
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High molecular weight polycyclic aromatic hydrocarbons (HMW PAHs) increase in hydrophobicity with increases in their molecular weight and ring angularity. Microbial strategies to deal with PAH hydrophobicity include biofilm formation, enzyme induction, and biosurfactants, the effect of which is variable on PAH metabolism depending on the surfactant type and concentration, substrate, and microbial strain(s). Aerobic HMW PAH metabolism proceeds via mineralization, partial degradation, and cometabolic transformations. Generally, bacteria and nonlignolytic fungi metabolize PAHs via initial PAH ring oxidation by dioxygenases to form cis‐dihydrodiols, which are transformed to catechol compounds by dehydrogenases and other mono‐ and dioxygenases to substituted catechol and noncatechol compounds, all ortho‐ or metacleaved and further oxidized to simpler compounds. However, lignolytic fungi form quinones and acids to CO2. This review discusses the pathways for HMW PAH microbial metabolism. © 2008 Wiley Periodicals, Inc.  相似文献   
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This article summarizes the bench‐scale studies to identify pyrene‐degradation pathways using an environmental microbial isolate, Pseudomonas fluorescens 29L. Strain 29L was grown on 50 mg of pyrene per liter of mineral medium. At a pyrene biodegradation rate of 14.7 mg/L of medium/day, 82.38 percent of pyrene was degraded in six days. Naphthalene and phenanthrene accounted for 1.09 percent and 3.69 percent, respectively, of the carbon mass from pyrene in the late log phase. Substituted benzene compounds accounted for 26.10 percent of the carbon mass from pyrene in the late log phase. In the stationary phase, carboxylic acids accounted for 10.44 percent of the carbon mass from pyrene. Strain 29L mutants were used for enzyme assays. Pyrene is oxidized by monoxygenases and dioxygenases, and the oxidized ring is cleaved. These enzymes were induced in the presence of pyrene and their activities peaked in the late log phase. No gentisate 1,2‐dioxygenase activity was detected in Strain 29L wild type (WT), whereas mutant M15 did not show any catechol 2,3‐dioxygenase activity. This indicates the possibility of multiple branchings in the pyrene‐biodegradation pathways. In conclusion, multiple degradative pathways are operating concurrently in this strain. The study shows the versatility of Pseudomonas fluorescens Strain 29L for pyrene degradation. It also emphasizes the need to study pyrene‐degradation pathways in other microorganisms so as to enhance the bioremediation potential for the in situ treatment of pyrene‐contaminated sites. © 2008 Wiley Periodicals, Inc.  相似文献   
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We have demonstrated the use of Se as a tracer to quantitatively determine in situ SO4(2-) production from SO2 oxidation in clouds and fogs. Until now, it has not been possible to study the kinetics of SO2 oxidation because the aerosol sampling interval for Se determination was limited to 2 h or longer. Here we report results of 5-min aerosol measurements carried out at Lahore, Pakistan, during January 9-11, 2001, using new methodology for Se analysis coupled with hydride generation and ICP-MS detection. These improvements will enable the tracer technique to determine in situ SO4(2-) production in clouds and fogs on a time scale of several minutes and possibly 1 min. The method may prove useful for kinetic studies of in-cloud SO2 oxidation and in the study of other phenomena such as atmospheric mixing, cloud drop lifetimes, and aerosol formation that occur on the time scale of a few minutes.  相似文献   
80.
Akhtar S  Khan AA  Husain Q 《Chemosphere》2005,60(3):291-301
Immobilized peroxidases from Momordica charantia were highly effective in decolorizing reactive textile dyes compared to its soluble counterpart. Dye solutions, 50-200 mg/l, were treated with soluble and immobilized bitter gourd peroxidases (specific activity of 99.0 EU per mg protein). The decolorization of dyes with soluble and immobilized enzyme was maximum in the range of pH 3.0-4.0. The effect of different temperatures on the dye decolorization was monitored and it was observed that all the dyes were maximally decolorized at 40 degrees C. In order to examine the operational stability of the immobilized preparation, the enzyme was repeatedly exploited for the decolorization of the dyes from fresh batch of dye solutions. Even after 10 cycles in each case the immobilized preparation retained nearly 50% of the initial enzyme activity. The immobilized enzyme exhibited more than 90% of the original activity while the soluble enzyme lost 33% of the initial activity when stored for 40 d at room temperature. Mixtures of three, four and eight dyes were prepared and treated with soluble and immobilized bitter gourd peroxidase. Each mixture was decolorized by more than 80% when treated with immobilized enzyme. Dyeing effluent collected from local dyers was treated with both types of enzyme preparations. Immobilized enzyme was capable of removing remarkably high concentration of color from the effluent. TOC content of soluble and immobilized enzyme treated individual dyes, mixture of dyes and dyeing effluent was determined and it was observed that higher TOC was removed after treatment with immobilized enzyme.  相似文献   
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