Date of Publication :20th April 2018

Abstract: The appetite for up-to-date information about earth’s surface is ever increasing, as such information pro- vides a base for a large number of applications, including local, regional and global resources monitoring, land-cover and land-use change monitoring, and environmental studies. The data from remote sensing satellites provide opportunities to acquire information about land at varying resolutions and has been widely used for change detection studies. Change detection is a technology ascertaining the changes of specific features within a certain time interval. It provides the spatial distribution of features and qualitative and quantitative information of features changes. The main aims are to determine whether vegetation composition, structure and condition are changing over time or in response to a management intervention. . Remote sensing refers to the detection and recording of values of emitted or reflected electromagnetic radiation with sensors in aircrafts or satellites. The remote sensing datasets, such as satellite imageries and aerial photographs, would be a useful tool for monitoring purposes. This paper gives with comparing the performance of various vegetation indices parameters on semi arid region Madurai, Tamilnadu. There are forty index parameters calculated for this purpose. These parameters are grouped into first generation indices and second generation indices. The classified vegetation indices are further grouped into two main categories: indices created from the combination of two spectral bands, notably the red and near infrared , and indices created from the combinations of three or four bands. Some of the popular indices calculated are NDVI, SAVI, TVI, EVI, and PVI computed for the Resourcesat (IRS- P6) satellite imagery and the results are compared. From the vegetation classified output maps, the change map is computed. The change map is a measure of extent to which vegetation has been degraded in the study area during the two dcades.. In this paper, a method is proposed for vegetation cover estimation from multi spectral satellite data based on vegetation index. The timely difference between the vegetation cover of Madurai region, Tamilnadu during different time periods have been computed using post classification change detection comparison. The results show the extent of vegetation degradation during the concerned time periods and it is evident that the vegetation cover has been constantly decreasing in the Madurai region during the past two decades

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