International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part B7. Istanbul 2004 
  
Wetlands are defined as all submerged or water-saturated lands, 
natural or man-made, inland or coastal, permanent or 
temporary, static or dynamic, vegetated or non-vegetated, which 
necessarily have a land-water interface. This category occupies 
an area of 25.73 sq. km (4.20%) of corridor. The major wetland 
categories identified in the study area are Mangrove, Saltpans 
‘and Mudflats. 
3.5.1 Mangroves 
It appears bright red in color. It occurs along the coastal 
areas/inland areas of Krishna and Godavari River. This category 
occupies an area of 95.68 sq. km (6.55%) of corridor. 
Usually luxuriant vegetation prevails over large areas of the 
delta plains as saline mangrove swamps. Freshwater swamps or 
marshes, in humid tropical and subtropical regions along the 
intertidal environment are treated as builder of new landmass. 
Mangrove growth depends upon salinity of water, tidal, range, 
muddy strata, nature of shoals, ocean current protection and air 
temperature. 
3.5.2 Mudflats/Tidal Flat 
The mudflats are classified on the basis of their relation to the 
tidal conditions into the following, sub-tidal, inter-tidal and 
high tidal flat. However in the study area these have been 
grouped as one. The sub tidal zone is exposed only during low 
tide. The inter-tidal slopes lie between high water and low water 
mark, while the high tide flat lie above mean high water mark. 
The tidal flat environment is observed to be an elongated 
feature running parallel to the coast over tens of kilometer and 
are intersected by tidal channels and river estuarine system. The 
main part of the Kakinada Bay extensive tidal flats are 
developed along the gently sloping sea coasts with significant 
tidal flats in the Gautami estuary. Vasista estuary and in pandi 
lagoon. Tidal flat located between inter tidal zones, towards 
land is the supra tidal zone. 
This category is noticed along the coast of the study area and 
occupies an area of 107.91sq. Km (7.93%) of the corridor. 
3.5.3 WATER BODIES 
Rivers/streams/canals, sea and lake/reservoir/tank are the 
important water bodies seen in the study area. The river seen in 
the study area is Godavari. The Godavari flows into the Bay of 
Bengal through three major distributaries, namely Gautami 
Godavari, Vainateyam Godavari, and Vanish Godavari. 
Nilarevu is a very small distributaries branching out from 
Gautami Godavari. The Godavari delta has undergone phases 
of erosion and accretion through fluvial and marine agencies 
during its growth in recent times. Largely the detritus materials 
brought by the river from its drainage basin and subsequent 
effect of coastal processes over a long period in the modern 
Godavari delta were responsible for shaping the geomorphic 
units. The Godavari river channel from Dowaleswaram to the 
confluence of Gauthami is 90 Km, and of vainateyam and 
Vasista, 96 Km and with a maximum width of 2 km. The tidal 
effect is up to 42 km upstream in the river channel. River 
channel sediments are composed of mostly sands. 
4) CONCLUSIONS 
Satellite based remote sensing techniques have proved 
successful in providing a comprehensive, reliable and up-to date 
information on land use/land cover in the most cost effective 
manner. Knowledge of the agro-climate and agro-ecological 
conditions of the area will helped to identify ecologically 
sensitive locations with special reference to Environmental 
Sensitivity Index (ESI) and Reach Sensitivity Index (RSI) 
identified through modern methods like Digital Image 
processing and GIS for preparedness in case of oil spill 
incidents in offshore areas of east coast of Andhra Pradesh. 
ACKNOWLEDGEMENT 
The authors are thankful to the Director, NRSA and Dy. 
Director (RS & GIS), NRSA for encouragement and constant 
support for undertaking this study. 
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