Mapping of coastal eco system using Remote Sensing and spatial technology - experience from South India Eco Systems The fragile eco system of the Tamil Nadu coast is thus well recorded and appreciated from the geomorphic features.  Fig 5 For example, in tectonically rising Vedaranniyam (Point Calimere) region the study of satellite imagery (Fig. 3) and the followed up C14 dating of the beach ridges (Fig. 4) shows that the sea has receeded or the land has prograded to the tune of 55 kms (from Chettipulam to Kodiaykkarai) in between 6000 and 1000 years BP (Before Present) i.e. at the rate of overall 11 Mts. per year. The digitally processed IRS 1A imagery (Fig. 3) shows that rapid sand building activity is going on and off shore shoals have been built unto 22 km from Kodiyakkarai in the northwest towards Jaffna (Sri Lanka) in the south east during the last 1000 years. Such rapid land progradation and the sand building activity is attributed to land emergence along N-S faults in the area east of Tanjore and the gradual envelope of sand bodies by the violently active littoral currents. Similarly, along E-W trending Ramanathapuram - Rameswaram cymatogenic arching, because of such land emergence not only the sea has receeded over 40 - 50 kms leaving bundles of beach ridges but the Rameswaram island has also tilted towards northerly. GIS Animations Such critical observations made on the over all ecological systems of Tamil Nadu coast in general and Vedaranniyam and Rameswaram area in particular were animated using PC ARC/INFO. 
The mapping of the beach ridges from satellite data (Fig. 3) and the C14 dating of the beach ridges (Fig. 4) have shown that the land progradation is to the tune of 11 meters per year during the last nearly 6000 years. The same has been animated using ARC / INFO GIS. It has shown that India will get welded with Jaffna (Sri Lanka) through sand banks in another 300-350 years (Fig. 5). The probable sand accumulation pattern at of every 100 years have been shown in different colours. Similarly, the land - water distribution pattern were analysed between 1919 and 1990 for Rameswaram island by analysing oldest toposheets, aerial photographs and IRS images. These were amalgamated using PC ARC/INFO (Fig. 6). The same has shown that
Thus, the paper narrates the eco systems of Tamil Nadu coast, its modifications and the feasibility of animating the same using remote sensing and spatial technology for futuristic planning.
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