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91.
92.
Landslide Hazard Zonation using Remote Sensing and GIS: a case study of Dikrong river basin, Arunachal Pradesh, India 总被引:3,自引:0,他引:3
Landslides are among the most costly and damaging natural hazards in mountainous regions, triggered mainly under the influence
of earthquakes and/or rainfall. In the present study, Landslide Hazard Zonation (LHZ) of Dikrong river basin of Arunachal
Pradesh was carried out using Remote Sensing and Geographic Information System (GIS). Various thematic layers namely slope,
photo-lineament buffer, thrust buffer, relative relief map, geology and land use / land cover map were generated using remote
sensing data and GIS. The weighting-rating system based on the relative importance of various causative factors as derived
from remotely sensed data and other thematic maps were used for the LHZ. The different classes of thematic layers were assigned
the corresponding rating value as attribute information in the GIS and an “attribute map” was generated for each data layer.
Each class within a thematic layer was assigned an ordinal rating from 0 to 9. Summation of these attribute maps were then
multiplied by the corresponding weights to yield the Landslide Hazard Index (LHI) for each cell. Using trial and error method
the weight-rating values have been re-adjusted. The LHI threshold values used were: 142, 165, 189 and 216. A LHZ map was prepared
showing the five zones, namely “very low hazard”, “low hazard”, “moderate hazard”, “high hazard” and “very high hazard” by
using the “slicing” operation. 相似文献
93.
Anshu Miglani S. S. Ray R. Pandey J. S. Parihar 《Journal of the Indian Society of Remote Sensing》2008,36(3):255-266
The present study was carried out to evaluate the satellite-based hyperspectral data available from Hyperion onboard EO-1
of NASA for agricultural applications. The study was carried out for Daurala block of Meerut district, using data of March
2005. The preliminary data analysis showed that there are 196 usable bands out of a total of 242 bands. Principal component
(PC) analysis showed that about 99% of the information explained in 10 PCs. The atmospherically corrected reflectance, derived
from satellite data had good agreement with the ground reflectance, observed using handheld spectroradiometer, with r2 ranging from 0.85 to 0.98. A set of twenty most usable bands was selected by the criteria of maximum contribution to first
five PCs and the band combinations with least inter-band correlations. 相似文献
94.
Rajiv Pandey Nandini Maithani Roberta Aretano Giovanni Zurlini Kelli M. Archie Ajay K. Gupta Vishnu Prasad Pandey 《山地科学学报》2016,13(8):1503-1514
The present study proposes an index to assess the potential for adaptation to climate change for households in the mountainous regions. The index provides a realistic approach to recognize social and natural factors which contribute to successful adaptation and addresses several household functions, such as social networking, livelihood strategy, adjustment strategies, resource availability and accessibility. The proposed Adaptation Capability Index (ACI) is analytically defined, mathematically formulated and field tested on mountainous households in urban and semi-urban regions of the Uttarakhand Himalaya in India. To gather data on the topic relevant to the ACI, a household scale questionnaire was developed and administered to 120 heads of households through face-to-face interviews. The results highlight higher adaptive capability of urban households and low adaptation capacity of rural households due to poor farm productivity, low accessibility and availability of resources and technological input. Future programs and policies must include and implement regulations to remedy attributive factors responsible for higher adaptation. This paper may be applicable to other mountainous regions and may provide insights for effective adaptation strategies to climate change. 相似文献
95.
M. A. Rasheed P. L. Srinivasa Rao Annapurna Boruah Syed Zaheer Hasan Bougi Mohamoud Mohamed Seddik Disha Pandey T. Harinarayana 《Journal of the Geological Society of India》2016,88(4):433-439
The aim of the present work is to define the geo-microbial signatures along with trace metals, and to investigate whether the geo-microbial anomalies have correlation with trace metal anomalies in Ahmedabad block of Cambay basin. The surface geochemical techniques are based on seepage of light hydrocarbon gases from the oil and gas pools to the shallow surface and can bring up near-surface oxidation reduction zones that favor the development of a diverse array of chemical and mineralogical changes. The paper reports the role of hydrocarbon microseepage in surface alterations of trace metal concentrations and hydrocarbon oxidizing bacteria and its interrelationship. For the purpose a total of 90 soil samples are collected in grid pattern of 2 x 2 km interval. The paper reports the chemical alterations associated with trace metals in soils that are related to hydrocarbon microseepages above some of the major oil and gas fields of this petroliferous region. The concentrations of V (0 to149 ppm), Cr (2 to 192 ppm), Cu (4 to 171 ppm), Se (98 to 440 ppm), Zn (56 to 1215 ppm) are obtained. It is observed that the concentrations of trace elements are tremendously increased when they are compared with their normal concentrations in soils. In this study the hydrocarbon oxidizing bacterial counts ranged between 1.0 x 103 and 1.59 x 106 cfu/g of soil sample respectively. The attempt has made for the first time, which revealed good correlation as both these anomalies are found as apical in relation. Integrated studies between trace elements and hydrocarbon oxidizing bacterial anomalies showed positive correlation with existing oil and gas wells in the study area. 相似文献
96.
In this work an exhaustive study of static massive configurations with a constant local adiabatic exponent (1) has been made under various physical conditions at the centre. The static parameters of these structures have been calculated at the extreme causality condition. These structures have been used to model neutron stars and the various neutron star parameters have been calculated. The radial pulsation and rotation of these configurations have also been discussed. 相似文献
97.
Using a large set of rainfall–runoff data from 234 watersheds in the USA, a catchment area‐based evaluation of the modified version of the Mishra and Singh (2002a) model was performed. The model is based on the Soil Conservation Service Curve Number (SCS‐CN) methodology and incorporates the antecedent moisture in computation of direct surface runoff. Comparison with the existing SCS‐CN method showed that the modified version performed better than did the existing one on the data of all seven area‐based groups of watersheds ranging from 0·01 to 310·3 km2. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
98.
The developmental activities, particularly the construction of hydroelectric projects are causing a great loss of biodiversity
in the Indian Himalayan Region. The Himachal Pradesh, a part of IHR is well known for the development of hydroelectric projects.
The Parbati H.E. Project is amongst the major projects of the State. The different stages of the project are all causing loss
of biodiversity of the area. Stage III of the Parbati H.E. Project is a run of the river scheme on the Sainj River downstream
of Power House of Parbati H.E. Project Stage II. The project shall utilize regulated discharge of Parbati H.E. Project Stage
II and inflow of River Sainj for power generation, and has been contemplated as a peaking station operating in tandem with
Stage II. The present study has been undertaken to see the impact of hydroelectric project on the biodiversity, particularly
on medicinal plants. A total of 104 species of medicinal plants, belonging to different life forms, i.e., trees (23 spp.),
shrubs (22 spp.), herbs (57 spp.) and ferns (2 spp.) were recorded. The species have been analyzed and studied for their distribution,
classification, altitudinal zones, part (s) used, indigenous uses, nativity, endemism and rarity. DDifferent parts of these
species, such as whole plants, roots (including rhizomes and tubers), leaves, flowers, fruits, seeds, stems, barks, spikes,
nuts and insect galls are used by the inhabitants for curing various diseases and ailments. 30 species are native to the Himalayan
region, 9 species native to the Himalayan region and adjacent countries also and 65 species are non-natives. 9 species are
near endemics. Considering the whole Himalaya as a biogeographic unit (sensu lato), the near endemics are endemic to the Himalaya. Among these species, Zanthoxylum armatum is categorized as Endangered and Valeriana wallichii as Vulnerable. Hedychium spicatum, Rhus javanica, Berberis lycium, Thalictrum foliolossum, Salvia lanata, Rubia cordifolia and Bergenia ligulata may be considered as threatened species due to their over exploitation for trade. 90 species are propagated by seeds, 8 species
by seeds and rhizomes/roots/tubers, 4 species by seeds and cuttings, and 2 species by sori. A management plan for the cultivation
and conservation of the medicinal plants in the dam submergence area, and the commercially viable medicinal plants with high
value in the catchment area is suggested. 相似文献
99.
100.
Rajat M. Thomas Saleem Zaroubi Benedetta Ciardi reas H. Pawlik Panagiotis Labropoulos Vibor Jeli Gianni Bernardi Michiel A. Brentjens A. G. de Bruyn Geraint J. A. Harker Leon V. E. Koopmans Garrelt Mellema V. N. Pandey Joop Schaye Sarod Yatawatta 《Monthly notices of the Royal Astronomical Society》2009,393(1):32-48