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971.
S. S. Samant Man Singh Manohar Lal Shreekar Pant 《山地科学学报》2007,4(3):259-274
In the Indian Himalayan Region predominantly rural in character, livestock is one of the main sources of livelihood and integral part of the economy. Livestock mostly rely on fodder from wild. The diversity, distribution, utilization pattern, nativity, endemism, rarity, seasonality of availability, nutritive values, perceived economic values and pressure use index of livestock have not been studied. The present study attempts to enumerate 150 species of fodder representing trees (51 spp.), shrubs (54 spp.) and herbs (45 spp.). Poaceae (19 spp.) and Fabaceae (13 spp.) amongst families and Salix (6 spp.), Ficus, Clematis, and Desmodium (5 spp., each) amongst genera are rich in species. Maximum species were found in the 1801 ~ 2600 m zone, and the remaining two zones showed relatively low diversity. Out of the 150 species, 109 are used in summer, 5 winter and 36 throughout year. During rainy season, mostly grasses are used as fodder. Only 83 species are native to the Himalayan region, one species, Strobilanthus atropuroureus is endemic and 35 species are near endemic. The nutritive values of the fodder species were reviewed, and economic values and status of the species were also assessed. The pressure use index of the species was calculated on the basis of cumulative values of the utilization pattern, altitudinal distribution, availability, status, nativity and endemism. Amongst the species, Grewia oppositifoilia, Morus serrata, Indigofera heterantha, Quercus leucotrichphora, Ulmus villosa, U. wallichiana and Aesculus indica showed highest PUI indicating high preference and pressure. Season wise prioritization of the species for different altitudinal zones has been done. Appropriate strategy and action plan have been suggested for the conservation and management of fodder species. 相似文献
972.
Karakoram Himalaya(KH) has continental climatic conditions and possesses largest concentration of glaciers outside the polar regions. The melt water from these glaciers is a major contributor to the Indus river. In this study, various methods have been used to estimate the ice volume in the Karakoram Range of glaciers such as Coregistration of Optically Sensed Images and Correlation(COSI-Corr) method and Area-Volume relations. Landsat 8 satellite data has been used to generate the ice displacement, velocity and thickness map. Our study for 558 Karakoram glaciers revealed that the average ice thickness in Karakoram is 90 m. Ground Penetrating Radar(GPR) survey has been conducted in one of the KH glacier i.e. Saser La glacier and the collected GPR data is used for the validation of satellite derived thickness map. GPR measured glacier thickness values are found comparable with satellite estimated values with RMSE of 4.3 m. The total ice volume of the Karakoram glaciers is estimated to be 1607±19 km3(1473±17 Gt), which is equivalent to 1473±17 km3 of water equivalent. Present study also covers the analysis of glacier surface displacement, velocity and ice thickness values with reference to glacier mean slope. 相似文献
973.
Singh S 《Population geography : a journal of the Association of Population Geographers of India》1988,10(1-2):1-17
The author examines the rural spatial distribution patterns in four main agricultural communities of India and Pakistan. Using 1931 census data to project 1988 population figures, a comparison is offered among ethnic relationships, religious backgrounds, castes, and migration patterns. The current socio-political status of these agricultural populations is also discussed. 相似文献
974.
Mehul R. Pandya Raghavendra Pratap Singh Sushma Panigrahy Jai Singh Parihar 《Journal of the Indian Society of Remote Sensing》2012,40(2):215-223
Quantitative remote sensing involving accurate estimation of vegetation properties relies greatly on the measurements of the
near infrared (NIR) channel because of unique interaction property between light and leaf. It is generally assumed that the
NIR measurements are made in the absence of atmospheric absorption. However, relatively weak water vapour absorption features
still persist in the NIR channel, which has bearing on the quantitative estimates of the vegetation properties and long-term
data series. This paper reports the results of a study that was carried out to infer the possible influence of the atmospheric
water vapour (WV) on the NIR measurements (0.77–0.86 μm) of Indian Remote Sensing (IRS) satellite sensors through radiative
transfer simulations using MODTRAN model. The study also suggests and evaluates the alternate band-positions for the NIR channel
to improve the IRS NIR measurements. It was observed that the water absorption features present around 0.810 μm reduces the
WV transmission of IRS NIR channel from 1 to 0.91 when atmospheric WV content increased from 0 to 6 g/cm2 and thus hampered the NIR reflectance by 14% as compared to reference signal. A significant improvement of the order of 6.5
to 12% in the NIR reflectance and 4.2 to 7% in NDVI was observed, when IRS NIR channel was split into NIR1 (0.775–0.805 μm)
and NIR2 (0.845–0.875 μm) channels by avoiding the WV absorption features. The companion paper in this issue (Pandya et al.
2011) will support results of this simulation study through the EO1-Hyperion data analysis. 相似文献
975.
In the present paper, we have considered turbulent flow of an incompressible, viscous fluid which is nearly isotropic with an extra vector argument (i.e. rotational symmetry) and spatially homogeneous. The expression for acceleration covariance in presence of Coriolis force has been derived and solution has been obtained in terms of defining scalars. 相似文献
976.
T. P. Singh 《Journal of Astrophysics and Astronomy》1997,18(4):335-338
We give an elementary overview of the subject of gravitational collapse in classical general relativity. Recent theoretical
evidence for the formation of black-holes and naked singularities is summarised. 相似文献
977.
Shalini Singh 《GeoJournal》2005,64(3):215-223
Assuming the above quote as a true portrayal of pilgrims, this article attempts to describe the prototypical pilgrim from
amongst the wide array of contemporary religious and secular tourists. To achieve this end, two approaches have been adopted.
Firstly, the phenomenon/concept of pilgrimages have been discussed, so to distinguish it from the tourism phenomenon and;
Secondly, the geographical notion of genus loci has been employed to exemplify the fundamental quest for ‘geopiety’ attained
through the unification of the pilgrim’s intrinsic belief with its external location. The second part of the article illustrates
the forgoing through an exploration of Himalayan pilgrimages. This has been achieved with a discussion of the emerging practices
and recent trends in Himalayan pilgrimology. This appraisal alludes to Cohen’s quest for a ‘Theology of Tourism.’ The article
concludes with an examination of a specific genre of contemporary tourists in the Indian Himalayas, who have been identified
as ‘environmental pilgrims.’
相似文献
978.
The morphometric analysis of river basin helps to explore the interrelationship between hydraulic parameters and geomorphologic characteristics. The study has been conducted in the Upper Tons basin of Northern Foreland of Peninsular India. The river basin has been characterized using the topographical maps, CARTOSAT satellite image integrated using the GIS techniques. The drainage density analysis indicates lower values in the north-eastern regions and thus these regions can be categorized as better ground water potential zone. There are in total 10 sub-watersheds which have been delineated; SW-4 has maximum drainage density (4.75), stream frequency (5.61) and drainage texture (26.64) followed by SW-6–10. The prioritized sub-watershed numbers SW-4 and SW-6–10 need conservation practices because of their high erodibility and run-off. SW-1–3 and SW-5 regions have better permeable bed rocks and hence good for water harvesting. The areal parameter indicates elongated shape of basin and moderate to steeper ground slope. The results are supported by extensive field survey. This study can be applied for soil and water management, as well as disaster prevention from similar type of drainage basins. 相似文献
979.
The accuracy of DEMs shows wide variations from one terrain to another and it needs to be determined. This study evaluates NRSC (National Remote Sensing Centre, Hyderabad, India) CartoDEM V1 and V1.1R1 with respect to resampled ADS80 DEM for parts of the Himalayas. Both the test DEMs were properly registered with reference to resampled ADS80 DEM and then individually subtracted to get the difference DEMs. Visual and statistical analyses were performed to assess the quality of the tested DEMs in terms of visible terrain and vertical accuracy. For calculating the accuracies in different terrain classes, slope and aspect maps were generated from the ADS80 DEM. Properly registered Landsat5 TM data were used for the development of the land cover map with four classes. The overall vertical accuracy measured for CartoDEM V1 was 269.9 m (LE90), while CartoDEM V1.1R1 showed huge improvement in the accuracy with 68.5 m (LE90). 相似文献
980.