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Extraction of river network from ASTER data and SRTM DEM | |
Author | Aleinmar Htwe |
Call Number | AIT Thesis no.RS-05-06 |
Subject(s) | Geographic information systems Rivers--Remote sensing Topographic maps |
Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science |
Publisher | Asian Institute of Technology |
Abstract | Based on the combination of Geographic Information System tools (GIS), remote sensing products and digital elevation models (DEM), this study is attempted to delineate the watershed and river network. Nowadays, Geographical Information Systems (GIS) and Remote Sensing techniques are proving to be very valuable tools in many natural resources and environmental applications such as hydrologic modeling, debris flow simulations etc. The basic entity in such application is the river networks which is either manually delineated on topographic map sheets or derived from digital elevation model (DEM) data using computational methods. The study area, Phetchabun is located in the lower northern part of Thailand, 346 km from Bangkok The use of ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) Optical remote sensing data and SRTM (The Shuttle Radar Topography Mission) Radar remote sensing data permitted to extract DEMs directly. In this study, ENVI 3.6 ESRI software is used for manipulation and subsetting of data and for mosaicing SRTM tiles and converting their projection from Geographic to UTM. ArcView 3.2a (with Spatial Analyst 2.0a and Hydrological Modeling Tools 1.1) is used for Watershed delineation, drainage network extraction, overlaying with existing drainage network, and proximity analysis of modeled and actual river network. The DEM extracted from ASTER is 30 meter resolution, (30 m grid size) and DEM extracted from SR TM is 3 arc seconds (which is about 90 meters (295 feet). For most of the parts of the earth's surface, elevation data exists in analogue form as ·contour line on topographic maps. Generation of DEM from topographic maps is difficult and costly and time consuming, and sometimes topographic maps are not available in any case like required. Nowadays Digital elevation Models are more recently available in digital format from satellite imagery. On the other hand, the automatic extracted river network from the digital elevation models deviate from real world river network especially in some flat areas and the meanders of natural rivers. There is therefore a need to integrate a prior knowledge about the actual position of the real world river network. Therefore an approach for the combination of the utilization of river network information from analogue maps or optical remote sensing Image and topographic information from readily available space based DEM is still advantageous for flow simulation processes and hydrological applications. |
Year | 2005 |
Type | Thesis |
School | School of Advanced Technologies (SAT) |
Department | Department of Information and Communications Technologies (DICT) |
Academic Program/FoS | Remote Sensing (RS) |
Chairperson(s) | Honda, Kiyoshi ; |
Examination Committee(s) | Chen, Xiaoyong ;Dutta, Dushmanta; |
Scholarship Donor(s) | Government of Japan; |
Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2005 |