Spatial Analysis with RS/GIS
Author：Luo lihui
Introduction
Remote sensing (RS) collect data on dangerous or inaccessible areas. RS applications include monitoring deforestation, glaciers, Arctic and Antarctic regions, and so on. RS replaces costly and slow collection on the ground, ensuring in the process that areas or objects are not disturbed. Remote sensing has some applications include different areas of earth sciences such as natural resource management, agricultural fields such as land usage and conservation, and national security.
Geographic Information System (GIS) is a tool that allows users to create interactive queries, analyze the spatial information, edit data, maps, and present the results of all these operations. GIS technology can be used for scientific investigations, resource management, Environmental Impact Assessment, Urban planning, and so on. For example, GIS might be used to find wetlands that need protection from pollution.
The course: Application of Geo-informatics to Area Studies
The course were based on the results of RS/GIS analyses in five areas of Asia includes Mekong Delta, Beng River Basin, Chieng Dong Village, Don Daeng Village, Weixi-Shangri-La Road. It is important that we regard the development of the society.
We need to evaluate the difference between two areas in the Mekong Delta by RS maps and some pictures about the actuality in the Mekong Delta. For examples, Natural landform, Land development, Land condition, and so on.
In the Case Study of the Beng River Basin of Laos, we discussed the change in land use and the possible direct and indirect causes of the land use changes. Social changes have the important impact to the country's economy.
In the Case Study of Don Daeng Village of Thailand, we discussed the relations between the changes in Farm economy and the water resource with RS maps and GIS.
We need to collect data in years past relate to the areas, includes RS maps and the data about social events and economic situation., then apply the Spatial analysis with RS/GIS, find out the reasons and relations refer the area where we want to research.
The Spatial analysis with RS/GIS includes data modeling, Topological modeling, Networks, Cartographic modeling, Map overlay, Automated cartography, Geostatistics, Geocoding, Reverse geocoding, and so on.
A case study of western Jilin, China
The impact of land-use on surface runoff and soil erosion is still poorly understood at basin scale. Thus in the Western Jilin Ecosystem, surface runoff and soil erosion were measured against identified land-use types in the basin. Due to the spatial nature of the analysis, RS maps, ArcGIS software, some statistical methods (Geostatistics) and the WetSpass model were used in the simulation process. the model was extended with the Dynamic Sediment Balance Equation, to simulate and quantify soil erosion. A hypothetical natural grassland scenario was developed for the study area and compared with the present land-use management conditions. An overall decrease in runoff and soil erosion was observed as the conditions changed from the present land-use management to the hypothetical natural grassland state. Under the present land-use management, urban settlements exhibited the highest surface runoff but one of the least soil erosions, while bare-lands showed the highest soil erosion. It was more generally observed that runoff and erosion varies with vegetation type/density.
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