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Atanu Raha Susmita Das Kakoli Banerjee Abhijit Mitra 《Biodiversity and Conservation》2012,21(5):1289-1307
Climate change induced sea level rise (SLR) added with anthropogenically altered environment leads to rapid land dynamics
in terms of erosion and accretion; and alteration in species diversity and productivity, more pronouncedly in sensitive ecosystems
such as river deltas. Here, we tried to analyze the historical records to understand the SLR with respect to hydrological
conditions, sedimentation and morphological processes. We analyzed the land transformation of few islands in Indian Sunderbans
using maps and satellite images in increasing order of temporal frequency between 1924 and 2008, which revealed that both
the erosion and accretion processes go hand in hand. Increase of downstream salinity due obstruction in upstream has led to
decrease in transparency of water causing decrease in phytoplankton and fish, density and diversity in the central sector
of Indian Sunderbans. Analysis of the above ground biomass of three dominant mangrove species (Sonneratia apetala, Avicennia alba and Excoecaria agallocha) revealed better growth in the western sector compared to the central sector. The study reveals the cumulative effect of
climate change and anthropogenic disturbance on the diversity and productivity in World’s largest ecosystem; and advocates
mangrove plantation and effective management of freshwater resources for conservation of the most vulnerable and sensitive
ecosystem. 相似文献
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Recent experiments show that synchronous events can appear to an observer to occur at different times. Neural processing time delays are offered as an explanation of these temporal illusions, but equating perceived time with processing time leads to some thorny philosophical problems. 相似文献
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Ashwagandha, the root ofWithania somnifera Dunal, is an ancient drug used in India by practitioners of Ayurvedic mediicne and as a household remedy. The drug is now official in the Indian Pharmacopoeia. Results of a survey regarding the cultivation, collection and marketing of this drug are described. 相似文献
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The implementation of Project Tiger in India, 1973–1974, was justly hailed as a triumph of international environmental advocacy. It occurred as a growing number of conservation-oriented biologists were beginning to argue forcefully for scientifically managed conservation of species and ecosystems – the same scientists who would, by the mid-1980s, call themselves conservation biologists. Although India accepted international funds to implement Project Tiger, it strictly limited research posts to Government of India Foresters, against the protests of Indian and US biologists who hoped to conduct the scientific studies that would lead to better management and thus more effective conservation of the tiger. The foresters were not trained to conduct research, and in fact did not produce any of significance for the first 15 years of Project Tiger’s existence. The failure of biologists to gain access to India’s tigers in the 1970s was caused by many factors, but not least among them was a history of disdain among conservation-oriented biologists for government officials managing reserves, and the local politics of conservation. Project Tiger, then, serves as a case study for the discussion of the intersection of conservation biology with non-scientific concerns, including nationalism and the desire of the Indian government to more completely control its land.1I would like to thank the participants in the 2003 Southwest Colloquium for the Life Sciences for their constructive comments on an earlier version of this paper, as well as the two unusually helpful (anonymous) reviewers. 相似文献
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Hongbo Zhang Michael J. Agnew 《Computer methods in biomechanics and biomedical engineering》2013,16(15):1693-1703
The critical time interval (CTI) is a parameter that has been used to distinguish open-loop from closed-loop control during upright stance. The aim of this study was to develop a new method to determine CTIs. The new approach, termed the intermittent critical time interval (ICTI) method, was motivated from evidence that upright standing is an intermittent rather than an asymptotic stability control process. For this ICTI method, center-of-pressure time series are first transformed to the time–frequency domain with a wavelet method. Subsequently, the CTI is assumed equal to the time span between two local maxima in the time–frequency domain within a distinct frequency band (i.e., 0.5–1.1 Hz). This new method may help facilitate better estimates of the transition time interval between open and closed-loop control during upright stance and can also be applied in future work such as in simulating postural control. In addition, this method can be used in future work to assess temporal changes in CTIs. 相似文献
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D. R. Stoddart 《Journal of Zoology》1972,167(2):207-217
Records of pinnipeds and sirenians are rare in the western Indian Ocean away from continental coasts. In the case of pinnipeds there are apparently no records at all in this area, except for occasional stray Elephant seals Mirounga leonina as far north as Mauritius and Rodriguez, and a single record of an undetermined species in the southern Maldive Islands: the Indian Ocean now lacks any counterpart of the Monk seals of the Caribbean and the Pacific (King, 1956, 1964). In the case of sirenians, Dugongs are widely distributed round the continental coasts of the Indian Ocean, including Madagascar, the Comoros, and Ceylon, but there is much less information concerning them on more remote Indian Ocean islands. This paper draws attention to hitherto unnoticed reports of animals which could be either pinnipeds or sirenians made by 18th and early 19th century navigators, and reviews some of the published evidence for the existence of these animals in the 17th and 18th centuries in the Mascarene Islands. It is shown that many of the reef islands of the tropical western Indian Ocean were formerly inhabited by seals, of undetermined species and now extinct, and that some of the early references to Dugongs in fact concerned seals. 相似文献
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Vinesh P.V. Biswajit BrahmaRupinder Kaur Tirtha Kumar DattaSurender Lal Goswami Sachinandan De 《Gene》2013
The study aimed at characterization of buffalo β-casein gene and its promoter by PCR-SSCP analysis. Complete β-casein exon VII region analysis revealed two SSCP band patterns, with pattern-I representing predominant allele B (85%) present in homozygous (genotype BB) condition and pattern-II representing a rare allele A1 present in heterozygous condition (genotype A1B). Sequencing of two patterns revealed three nucleotide substitutions at codon 68, 151 and 193 of exon VII. The cDNA sequence of buffalo β-casein gene indicated three further nucleotide substitutions between allele A1 and B at codon 10, 39, and 41. Analysis of β-casein proximal promoter region (− 350 upstream to + 32) revealed four SSCP band patterns. These SSCP patterns corresponded to nucleotide substitutions at seven locations within 382 bp 5′ UTR region of β-casein gene. Haplotype analysis suggested pattern-I of exon VII (wild type) was associated with three types of promoters and pattern-II of exon VII (rare type) corresponded to one exclusive type of promoter. The study suggested two haplotypes of exon VII and four haplotypes of promoter for buffalo β-casein. 相似文献
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《Cryptogamie Bryologie ☆》2000,21(3):241-245
Cytological studies are made in seven south Indian moss taxa. The chromosome numbers of Atrichum longifolium Card. et Dix. (n = 7), Enthostodon pilifer Mitt. (n = 26) and Pohlia camptotrachela (Ren. et Card.) Broth. (n = 11) are reported for the first time. An anaphasic bridge is observed in Atrichum pallidum Ren. et Card. Telophasic laggards are observed in Atrichum pallidum, Enthostodon pilifer and Pohlia camptotrachela. 相似文献
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K A Kennedy A Sonakia J Chiment K K Verma 《American journal of physical anthropology》1991,86(4):475-496
In 1982 a fossil hominid calvaria was found in a middle Pleistocene deposit in the central Narmada valley of Madhya Pradesh, India, and was assigned to the new taxon Homo erectus narmadensis. Subsequently, morphometric studies of the specimen were conducted by two separate research teams from France and the United States, both in collaboration with Indian colleagues. Results of the most recent study, which includes morphometric and comparative investigations, lead to the conclusion that "Narmada Man" is appropriately identified as Homo sapiens. While the calvaria shares some anatomical features with Asian Homo erectus specimens, it exhibits a broader suite of morphological and mensural characteristics suggesting affinities with early Homo sapiens fossils from Asia, Europe, and Africa as well as demonstrating that the Narmada calvaria possesses some unique anatomical features, perhaps because the specimen reflects the incoherent classificatory condition of the genus Homo. 相似文献
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Taylor A. Steeves 《Economic botany》1952,6(2):107-142
Once an important food for many Indian tribes in the Northwest Territory, wild rice is still used by the remaining Chippewas, and more than one million pounds of it are gathered annually in Manitoba and Minnesota as a commercial enterprise for modern culinary use in Canada and the United States. 相似文献
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