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Effect of Grazing and Climatic Changes on Alpine Vegetation of Tungnath,Garhwal Himalaya,India 总被引:3,自引:0,他引:3
Effect of grazing and changing climate on vegetation composition of alpine pasture at Tungnath, Garhwal Himalaya was observed. Growth form pattern and phytosociological attributes were analyzed during 1988 under grazed (exposed to extensive grazing) and ungrazed (protected from grazing) conditions. These observations were repeated during 1998. It was observed that number of early growing species and long vegetative growth cycle species had increased at both sites in 1998 in comparison to 1988. Further, some species, viz., Poa alpina, Polygonum spp., Ranunculus hirtellus, Anemone spp., are predominantly found near the timberline-subalpine region. These species are less palatable and were present at both sites with higher dominance (TBC) and niche width in 1998 indicating wide distribution of the species along an altitudinal gradient. These observations indicated the migration of these species towards upper slopes of alpine. Species diversity was also higher after ten years. However, it is clear that climatic changes alone are not responsible for these vegetational shifts. In fact, human-induced changes are the main reason for habitat destruction and changes in vegetation composition of the alpine region of Garhwal Himalaya. Before final conclusions can be made, long-term studies on vegetation composition and changes are needed, especially in Himalayan region. 相似文献
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Baghel VS Singh J Gopal K 《Journal of environmental biology / Academy of Environmental Biology, India》2003,24(3):349-356
An attempt has been made to study antimicrobial resistance among the coliforms, faecal coliforms and faecal streptococci isolated from the runoff of the Gangotri glacier. The number of multiple antibiotic resistances (MAR) coliform isolates increases from upper stretch (33.33%) to lower stretch (83.33%). All faecal coliforms (100%) and faecal streptococci (100%) of lower stretch of study area showed multiple antibiotic resistances. Among coliforms, the value of Antibiotic resistance index (ARI) was found maximum in lower stretch (0.34) followed by middle stretch (0.29) and upper stretch (0.25). 相似文献
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Verma V Prasad Y Singh BR 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(5):573-577
Flavobacterium columnare (FC) and Myxobacterium sp. recorded persistently associated in fish hatchery and culture system of Himalayan and Sub - Himalayan regions were found to be pathogenic. The pH and salinity played a significant role on the pathogenicity of these potent pathogens in case of Clarias batrachus and Heteropneustes fossilis. LD50 value of FC was 10(4.5) CFU in both the fishes and those of Myxobacterium sp it was 10(6) CFU ml(-1) fish(-1). Fish challenged with F. columnare and Myxobacterium sp. (@ 0.2 ml fish(-1)) individually consisting 10(5-6) cfu ml(-1) exhibited explicit symptoms of columnaris disease and marked with ulceration and saddle back lesion on the dorsal side of body. Maximum reisolation of inoculated bacteria was recorded at pH 7.0 and 7.5 and at 0.0-0.5 (F. columnare) and 0.0-1.0% (Myxobacterium sp.) salinity. Foregoing results elucidated that F. columnare was more sensitive to salinity in comparison to Myxobacterium sp. and their pathogenicity significantly (p<0.05) depends on the salinity and pH that might be one of the physical factors to control their proliferation. 相似文献
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Sharma Baby Kumari Nilima Mathur Shruti Sharma Vinay 《Environmental science and pollution research international》2022,29(1):312-331
Environmental Science and Pollution Research - The projected increase of the global textile industry to USD1002.84 billion in 2027 indicates a simultaneous increase in water pollution due to... 相似文献
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Sustainable technologies for on-site domestic wastewater treatment: a review with technical approach
Sharma Meena Kumari Tyagi Vinay Kumar Singh Nitin Kumar Singh Surya Pratap Kazmi Absar Ahmad 《Environment, Development and Sustainability》2022,24(3):3039-3090
Environment, Development and Sustainability - The rapid population growth has rendered the centralized sewerage systems a non-realistic option in sparsely populated areas, particularly in... 相似文献
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Poonam Saini Suphiya Khan Mamta Baunthiyal Vinay Sharma 《Environmental monitoring and assessment》2013,185(2):2001-2008
The prevalence of fluorosis is mainly due to the consumption of more fluoride (F?1) through drinking water, vegetables, and crops. The objective of the study was mapping of F?1 endemic area of Newai Tehsil, Tonk district, Rajasthan, India. For the present study, water, soil (0–45 cm), and vegetation samples were collected from 17 villages. Fluoride concentration in water samples ranged from 0.3 to 9.8 mg/l. Out of 17 villages studied, the amounts of F?1 content of eight villages were found to exceed the permissible limits. Labile F?1 content and total F?1 content in soil samples ranges 11.00–70.05 mg/l and 50.3–179.63 μg g?1, respectively. F?1 content in tree species was found in this order Azadirachta indica 47.32–55.76 μg g?1 > Prosopis juliflora 40.16–49.63 μg g?1 > Acacia tortilis 34.39–43.60 μg g?1. While in case of leafy vegetables, F?1 content order was Chenopodium album 54.23–98.42 μg g?1 > Spinacea oleracea 30.41–64.09 μg g?1 > Mentha arvensis 35.48–51.97 μg g?1. The order of F?1 content in crops was found as 41.04 μg g?1 Pennisetum glaucum > 13.61 μg g?1 Brassica juncea > 7.98 μg g?1 Triticum sativum in Krishi Vigyan Kendra (KVK) farms. Among vegetation, the leafy vegetables have more F?1 content. From the results, it is suggested that the people of KVK farms should avoid the use of highly F?1 containing water for irrigation and drinking purpose. It has been recommended to the government authority to take serious steps to supply drinking water with low F?1 concentration for the fluorosis affected villages. Further, grow more F?1 hyperaccumulator plants in F?1 endemic areas to lower the F?1 content of the soils. 相似文献
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Tyagi VK Sahoo BK Khursheed A Kazmi AA Ahmad Z Chopra AK 《Environmental monitoring and assessment》2011,179(1-4):123-135
Global positioning systems (GPS) are increasingly being used for habitat mapping because they provide spatially referenced data that can be used to characterize habitat structure across the landscape and document habitat change over time. We evaluated the accuracy of using a GPS for determining the size and location of habitat patches in a riverine environment. We simulated error attributable to a mapping-grade GPS receiver capable of achieving sub-meter accuracy onto discrete macrophyte bed and wood habitat patches (2 to 177 m(2)) that were digitized from an aerial photograph of the Laramie River, Wyoming, USA in a way that emulated field mapping. Patches with simulated error were compared to the original digitized patches. The accuracy in measuring habitat patches was affected most by patch size and less by patch shape and complexity. Perimeter length was consistently overestimated but was less biased for large, elongate patches with complex shapes. Patch area was slightly overestimated for small patches but was unbiased for large patches. Precision of area estimates was highest for large (>100 m(2)), elongate patches. Percent spatial overlap, a measure of the spatial accuracy of patch location, was low and variable for the smallest patches (2 to 5 m(2)). Mean percent spatial overlap was not related to patch shape but the precision of overlap was lower for small, elongate, and complex patches. Mapping habitat patches with a mapping-grade GPS can yield useful data, but research objectives will determine the acceptable amount of error and the smallest habitats that can be reliably measured. 相似文献
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Our previous study suggested that toxicokinetic parameters of fluoride were significantly changed on the 30th day as compared with 1st day, after repeated oral administration of sodium fluoride alone for 30 days in goats. The purpose of this study was to investigate whether aluminum sulfate has ameliorative effect on the toxicokinetics of fluoride. For this, sodium fluoride (20 mg kg?1 b. wt.) along with aluminum sulfate (150 mg kg?1 b. wt.) was administered in goats for 30 days to investigate its effect on toxicokinetics of fluoride on days 1 and 30. The fluoride levels against time were adequately described by one compartment open model. The peak plasma level of fluoride was observed at 2 h. The toxicokinetics data revealed a nonsignificant decrease in β (elimination rate constant) and C max (the maximum plasma concentration) and increase in t 1/2 K a (absorption half-lives), t 1/2 β (elimination half-lives), area under the plasma (AUC) concentration versus time curve and mean residence time (MRT) was observed for the last dose from their respective first dose values. On the basis of changes in the toxicokinetic parameters, it was concluded that repeated oral administration has cumulative effect on plasma fluoride level and concurrent oral administration of aluminum sulfate has ameliorative action on the toxicokinetics of fluoride in goats. 相似文献
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Jha MK Choubey PK Jha AK Kumari A Lee JC Kumar V Jeong J 《Waste management (New York, N.Y.)》2012,32(10):1919-1925
Printed circuit boards (PCBs) are the most essential components of all electrical and electronic equipments, which contain noteworthy quantity of metals, some of which are toxic to life and all of which are valuable resources. Therefore, recycling of PCBs is necessary for the safe disposal/utilization of these metals. Present paper is a part of developing Indo-Korean recycling technique consists of organic swelling pre-treatment technique for the liberation of thin layer of metallic sheet and the treatment of epoxy resin to remove/recover toxic soldering material. To optimize the parameters required for recovery of tin from waste PCBs, initially the bench scale studies were carried out using fresh solder (containing 52.6% Sn and 47.3% Pb) varying the acid concentration, temperature, mixing time and pulp density. The experimental data indicate that 95.79% of tin was leached out from solder material using 5.5M HCl at fixed pulp density 50g/L and temperature 90°C in mixing time 165min. Kinetic studies followed the chemical reaction controlled dense constant size cylindrical particles with activation energy of 117.68kJ/mol. However, 97.79% of tin was found to be leached out from solder materials of liberated swelled epoxy resin using 4.5M HCl at 90°C, mixing time 60min and pulp density 50g/L. From the leach liquor of solder materials of epoxy resin, the precipitate of sodium stannate as value added product was obtained at pH 1.9. The Pb from the leach residue was removed by using 0.1M nitric acid at 90°C in mixing time 45min and pulp density 10g/L. The metal free epoxy resin could be disposed-of safely/used as filling material without affecting the environment. 相似文献