Mapping of Impervious Surface using Spectral Angle Mapper (SAM) and NDVI Techniques, Case Study: Bhopal City

Impervious surface is essential to plot urban area development and the distribution of impervious surfaces can be used as a tool in environmental applications. Multispectral remote sensing based mapping has shown great potential in detailing land uses. Eastern area of Bhopal city has been analyzed of land use/land cover and it is derived from the results that some parts of land which has potentiality for agriculture has been gradually converted to urban plots leading to reduction of land for growing crops whereas some other areas, which tend to be impervious are left bare and it is a crucial fact that no agriculture is possible in such surfaces. Hence proper analysis regarding the surface area has to be done before executing development strategies. This paper emphasiseson the parts of land in the concerned area, that can be utilized for urban development. For comparison, four types of Endmember fractions (i.e. soil, vegetation, water and imperviousness) were used in this study. Selection of Endmember fraction was done by MNF, NDWI and NDVI. Spectral Angle Mapper (SAM), a classification technique, was used to map impervious surface using land sat data of the proposed area of study. SAM classification resulted in classifiying the study area into 5 landclass types with total imperviousness cover of about 27% of the area studied.