The methodology adopted in the study can be described in the following steps.
- The map of Guwahati City and its surrounding areas is digitized. The Cadastral data comprises of the characteristics of the drainage network, road and railway network and infrastructure facilities in the city.
- The satellite data were processed and classified using supervised classification method to prepare the land use/land cover map. The spatial and temporal changes in growth pattern are recognized from the digital data.
- Plot-wise urban land use map is prepared and attributes were assigned for every plot with full ownership and built-up information.
- A Decision Support System has been created to acquire information regarding every plot with its all attributes.
- The entire database is converted into a web supported format and is customized to provide query facilities for immediate and ready extraction of information through Web
The entire database has been developed by using data from diverse sources. The pattern of urban sprawl is identified and modeled using remotely sensed data. This helped in identifying the linear and radial pattern of growth and its rate. The analyses involved were land cover, land use, spatial and temporal changes and urbanization growth pattern recognition. The cadastral data comprises of the characteristics of land use / land cover, drainage network, roads and railway network and the administrative boundaries of 1991 from the toposheets provided by the Survey of India. The remote sensing data was classified for land use, based on themes - built up, transportation (road and rail network), water bodies (rivers, streams, etc.), agriculture and barren (uncultivable and waste land). For the change detection, temporal data between 1972 and 2002 (e.g. SPOT-1, Landsat TM, IRS-LISS-III and PAN) were used. This helped to identify the patterns of the change with respect to time.
Results and Discussion
The entire database has been created using ArcView 3.2 GIS Software. The SPOT – I Satellite data and LANDSAT TM Digital Data are utilized for land use and land cover mapping. The different land use classes identified from these images.
It is evident from the urban sprawl map that the city of Guwahati is rapidly increasing in the recent years and the growth is found mainly in south, south east direction of the original city (Figure 1). The infrastructure facilities are also growing in the city with its gradual expansion. Figure 2 shows the road network and the available infrastructure facilities found in the city. Figure 3 shows the land suitability map prepared using satellite data, which can provide a clear guidance to the city planners for proper planning of the city in terms proposed construction.