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81.
Various attributes can be derived from Digital Elevation Model (DEM), which are essential to analyze watershed physical characteristics. This paper discusses utility and accuracy of satellite DEM surfaces and their derivatives. Facilities available in various software packages were compared to generate DEM from satellite data and other sources. For test site at Chamba, Uttaranchal, DEMs produced from various algorithms were evaluated for accuracy of surface and its derivatives. Most of the algorithms have shown correlation coefficient of 0.99 and above but the desirable maximum error in spot height (1/5 of contour interval) is not achieved. Slope and aspect produced from various algorithms were comparable around 70-80%. Comparison of DEM surface and its derivatives were attempted for test sites at Shimla and Nahan using IRS-1C and SPOT PAN stereo pair, respectively. Model accuracy has shown that error in height is higher than planimetry. Surface derivatives from stereo DEM for Shimla and Nahan test sites have shown an overall accuracy of 56.5% and 59.2% for slope; 49.79% and 71.21% for aspect and 74.15% for topographic level slicing, respectively. Accuracy has improved when observed class value was lowered or put-up by one unit.  相似文献   
82.
The area under study forms a part of the Indo-Gangetic Alluvial Plain, in Muzaffar Nagar District (Uttar Pradesh). To understand the relation of stratigraphy and geogenesis on one hand, and landscape and pedogensis on the other hand, the study was undertaken through a 40 km. long E-W. Cross-section of the area, with augering upto a depth of five metres or more, Aerial photographs (1:25,000) were used for delineating the major land forms and selection of cross-section and observations sites. Care was taken to cover all the main physiographic units occuring in the survey area. Four distinct depositional phases in Upper Alluvial Plain and two in Lower Alluvial Plain by Ganges, while first braided and then meandering have been recognized. Soil were classified according to Soil Taxonomy (1975), being Inceptisols and Alfisols in the Upper Alluvial Plain and Entisols in the Lower Alluvial Plain.  相似文献   
83.
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