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Anjana Pant S. G. Chavan P. S. Roy K. K. Das 《Journal of the Indian Society of Remote Sensing》1999,27(3):133-139
Habitat analysis for sambar in terms of food, cover, water, space and extent of edge in Corbett National Park using remote sensing and GIS has been attempted. Other physical parameters include climate, topography, fire history, disturbance regimes, weeds etc. IRS-IB LISS II data (FCC, hardcopy) on 1:50.000 scale was interpreted to generate vegetation cover and density map. Other maps showing drainage, water bodies, roads, human habitations and contours were prepared using Survey of India topographical maps. During evaluation of sambar habitat information regarding habitat parameters and their tolerance was collected from existing literature as well as during field observations. Twenty-two transects of one km. length were laid down in all the strata randomly to collect information regarding the structure and composition of the forest and also habitat use (direct and indirect evidences) by sambar. This was then integrated using condition-based equations in the GIS domain to generate suitability maps. Actual sightings on the ground to a large extent supported the results. 相似文献
2.
H. S. Rajaraman G. Nagendra Babu S. J. Chavan K. K. Achar P. V. Ramesh Babu 《Journal of the Geological Society of India》2013,82(1):53-58
A medium tonnage unconformity proximal uranium deposit has been established at Chitrial by the Atomic Minerals Directorate in the Srisailam sub-basin. In this type of deposits, the association of uranium with potassic alteration (illitization) is well-documented. The present study is directed towards understanding such an association in the Chitrial area for which the uranium mineralized borehole core samples were collected and analyzed. It is observed that the average concentrations of K2O, Na2O, Rb, Ba and Sr in the granite of the Chitrial area are 5.35%, 1.78%, 252 ppm, 564 ppm and 52 ppm, respectively, and they show average critical elemental ratios of K/Rb, Ba/Rb and Rb/Sr as 191, 2.37 and 7.13, respectively. The granites show low K/Rb, low Rb/Ba and high Rb/Sr ratios compared to that of the average crust indicating its derivation from crustal source. The samples have higher values of uranium (av. 53 ppm), thorium (av. 66 ppm) and lead (av. 41 ppm). The U/Th ratio in the granite varies from 0.07 to 20.86 with an average of 1.68. They also exhibit high K2O/Na2O ratio typical of post-Archaean granite and very high values suggest the possibility of later potassium enrichment. 相似文献
3.
Shibendu Shankar Ray Namrata Jain R. K. Arora S. Chavan Sushma Panigrahy 《Journal of the Indian Society of Remote Sensing》2011,39(2):161-169
The study was carried out to investigate the utility of hyperspectral reflectance data for potato late blight disease detection.
The hyperspectral data was collected for potato crop at different level of disease infestation using hand-held spectroradiometer
over the spectral range of 325–1075 nm. The data was averaged into 10-nm wide wavebands, resulting in 75 narrowbands. The
reflectance curve was partitioned into five regions, viz. 400–500 nm, 520–590 nm, 620–680 nm, 770–860 nm and 920–1050 nm.
The notable differences in healthy and diseased potato plants were noticed in 770–860 nm and 920–1050 nm range. Vegetation
indices, namely NDVI, SR, SAVI and red edge were calculated using reflectance values. The differences between the vegetation
indices for plants at different levels of disease infestation were found highly significant. The optimal hyperspectral wavebands
to discriminate the healthy plants from disease infested plants were 540, 610, 620, 700, 710, 730, 780 and 1040 nm whereas
upto 25% infestation could be discriminated using reflectance at 710, 720 and 750 nm. 相似文献
4.
Kopparapu Vijaya Kumar Chakradhar Chavan Sariput Sawant K. Naga Raju Prachiti Kanakdande Sangita Patode Krishna Deshpande S. K. G. Krishnamacharyulu T. Vaideswaran V. Balaram 《Contributions to Mineralogy and Petrology》2010,159(6):839-862
Spatial and temporal variations in the geochemistry of an extrusive basaltic section of Deccan traps record progressive changes
in mantle melting and crustal filtration and are relevant to understand continental flood basalt (CFB) magmatism. In the present
work we have carried out detailed field, petrographic, density and magnetic susceptibility, and geochemical investigations
on a small, semi-continuous extrusive section in the eastern Deccan Volcanic Province (DVP) to understand the role of shallow
magma chambers in CFB magmatism. Four formations, Ajanta, Chikhli, Buldhana and Karanja crop out in the Gangakhed–Ambajogai
area with increasing elevation. Our studies indicate that: (1) the Karanja Formation represents a major magma addition, as
indicated by abrupt change in texture, increases in MgO, CaO, Ni, Cr, and Sr, and drastic decreases in Al2O3, Na2O, K2O, Rb, Ba, REE, bulk-rock density and magnetic susceptibility; (2) assimilation fractional crystallization, crystal-laden
magmas, and accessory cumulus phases influence the trace element chemistry of Deccan basalts; (3) the predicted cumulate sequence
of olivine gabbro–leucogabbro–oxide-apatite gabbro is supported by the observed layered series in a shallow magma chamber
within the DVP; (4) the initial magma was saturated with olivine, plagioclase, and augite, and final the pressure of equilibration
for the Gangakhed–Ambajogai section basalts is ~2 kbar (~6 km depth); (5) petrophysical parameters act as proxies for magmatic
processes; (6) a small layer of oxide-rich basalts may represent the latest erupted pulse in a given magmatic cycle in the
DVP; (7) parental basalts to some of the red boles, considered as formation boundaries, might represent small degree partial
melts of the mantle; (8) SW Deccan basaltic-types continue into the eastern DVP; and (9) in addition to the magma chamber
processes, dynamic melting of the mantle may have controlled DVP geochemistry. The present study underscores the importance
of mapping specific stratigraphic intervals in limited areas to understand mantle and magma chamber processes relevant to
CFB magmatism. 相似文献
5.
A. K. Sharma O. B. Gurav H. P. Gaikwad G. A. Chavan D. P. Nade S. S. Nikte R. N. Ghodpage P. T. Patil 《Astrophysics and Space Science》2018,363(4):83
The nightglow observations of OI 630.0 nm emission carried out from low latitude station Kolhapur using All Sky Imager (ASI) with \(140^{\circ}\) field of view (FOV) for the month of April 2011 are used. The images were processed to study the field aligned irregularities often called as equatorial plasma bubbles (EPBs). The present study focuses on the occurrence of scintillation during the traversal of EPBs over ionospheric pierce point (IPP). Here we dealt with the depletion level (depth) of the EPB structures and its effect on VHF signals. We compared VHF scintillation data with airglow intensities at Ionospheric pierce point (IPP) from the same location and found that the largely depleted EPBs make stronger scintillation. From previous literature, it is believed that the small scale structures are present near the steeper walls of EPBs which often degrades the communication, the analysis presented in this paper confirms this belief. 相似文献
6.
D. P. Nade A. K. Sharma S. S. Nikte G. A. Chavan R. N. Ghodpage P. T. Patil S. Gurubaran 《Earth, Moon, and Planets》2014,112(1-4):89-101
This paper presents observations of plasma blobs by nightglow OI 630.0 nm emissions using ground-based techniques, all sky imager and photometer from Kolhapur. The nightglow observations have been made at low latitude station, Kolhapur (16.42°N, 74.2°E, and 10.6°N dip lat.) during clear moonless nights for period of October 2011–April 2012. Generally, these occur 3 h after sunset (18:00 IST). Herein we have calculated velocities of plasma blobs using scanning method, introduced by Pimenta et al. (Adv Space Res 27:1219–1224, 2001). The average zonal drift velocity (eastward) of the plasma blobs were found to be 133 ms?1 and vary between 100 and 200 ms?1. The width (east–west expansion) and length (north–south expansion) of plasma blobs is calculated by recently developed method of Sharma et al. (Curr Sci 106(08):1085–1093, 2014b). Their mean width and length were in the range of 70–180 and 500–950 km respectively. The study shows that localized eastward polarization electric field plays an important role in the generation of plasma blobs. 相似文献
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Sankaran Adarsh Chavan Sagar Rohidas Ali Mumtaz Sindhu Archana Devarajan Dharan Drisya Sasi Khan Muhammad Ismail 《Natural Hazards》2021,106(3):1951-1979
Natural Hazards - This study investigated the multifractal characteristics of fine resolution (0.25ox0.25°) daily gridded rainfall fields of India over the period 1901–2013 to examine... 相似文献
8.
Climate change impacts on the water resources of American Indians and Alaska Natives in the U.S. 总被引：1，自引：1，他引：0
K. Cozzetto K. Chief K. Dittmer M. Brubaker R. Gough K. Souza F. Ettawageshik S. Wotkyns S. Opitz-Stapleton S. Duren P. Chavan 《Climatic change》2013,120(3):569-584
This paper provides an overview of climate change impacts on tribal water resources and the subsequent cascading effects on the livelihoods and cultures of American Indians and Alaska Natives living on tribal lands in the U.S. A hazards and vulnerability framework for understanding these impacts is first presented followed by context on the framework components, including climate, hydrologic, and ecosystem changes (i.e. hazards) and tribe-specific vulnerability factors (socioeconomic, political, infrastructural, environmental, spiritual and cultural), which when combined with hazards lead to impacts. Next regional summaries of impacts around the U.S. are discussed. Although each tribal community experiences unique sets of impacts because of their individual history, culture, and geographic setting, many of the observed impacts are common among different groups and can be categorized as impacts on—1) water supply and management (including water sources and infrastructure), 2) aquatic species important for culture and subsistence, 3) ranching and agriculture particularly from climate extremes (e.g., droughts, floods), 4) tribal sovereignty and rights associated with water resources, fishing, hunting, and gathering, and 5) soil quality (e.g., from coastal and riverine erosion prompting tribal relocation or from drought-related land degradation). The paper finishes by highlighting potentially relevant research questions based on the five impact categories. 相似文献
9.
Chavan Dhanaji Sitharam Thallak G. Anbazhagan P. 《Geotechnical and Geological Engineering》2022,40(4):1851-1872
Geotechnical and Geological Engineering - Desaturation of in-situ saturated sandy soils is emerging as a new cost effective and environment friendly liquefaction mitigation technique. In the... 相似文献
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R D Kaplay T Vijay Kumar Soumyajit Mukherjee P R Wesanekar Md Babar Sumeet Chavan 《Journal of Earth System Science》2017,126(5):71
We study the margin of South East Deccan Volcanic Province around Kinwat lineament, Maharashtra, India, which is NW extension of the Kaddam Fault. Structural field studies document \(\sim \)E–W strike-slip mostly brittle faults from the basement granite. We designate this as ‘Western boundary East Dharwar Craton Strike-slip Zone’ (WBEDCSZ). At local level, the deformation regime from Kinwat, Kaddam Fault, micro-seismically active Nanded and seismically active Killari corroborate with the nearby lineaments. Morphometric analyses suggest that the region is moderately tectonically active. The region of intense strike-slip deformation lies between seismically active fault along Tapi in NW and Bhadrachalam in the SE part of the Kaddam Fault/lineament. The WBEDCSZ with the surface evidences of faulting, presence of a major lineaments and intersection of faults could be a zone of intraplate earthquake. 相似文献
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