f various 
rshy area 
ding 
sased 
place 
relate to 
ancement 
moothing 
filter was 
] value of 
els in the 
ogeneous 
f natural 
angroves. 
vith false 
o the real 
longitude 
eet. This 
IAPRS & SIS, Vol.34, Part 7, "Resource and Environmental Monitoring", Hyderabad, India, 2002 
method of mapping mangroves was the simplest and gave very 
good approximation and a fair assessment of the mangrove 
ecosystem in the study area.IRS -IB has inherent limitation of 
its spatial resolution for identification of individual tree species. 
However cover type (tree species and density) mapping of 
mangrove vegetation could be possible with IRS data. .An 
example of such an attempt is the digital analysis of IRS data 
was done to determine the accuracy with which Rhizophora and 
Avicennia, the two important species found in the study area, 
could be identified. ^ Both supervised and unsupervised 
signature extraction techniques were used. Unsupervised 
clustering gave certain recognition maps and these when 
compared with ground information was found to be quite 
correct depicting the type of vegetation zonation. This was 
very clearly depicted in the study conducted over a testsite in 
Bhairavavanipalem, an area just to the South of the study area. 
Attempts were made delineate to more clearly different 
species, the rationing technique was used. A ratio map 
produced with ratio of bands 3 and 4.Recent studies conclude 
that the spectral merge of IRS - IC PAN data with LISS-II 
multispectral data of IRS-1B allows better discrimination of 
mangrove forest categories. An attempt has been made to 
determine the accuracy with which different species (sub 
categories) in the Rhizophora and Avicennia, could be 
identified. It was observed that due to spectral merging of IRS- 
IC (spatial resolution is 5.9 m) with IRS-1B LISS-II(spatial 
resolution is 36.25 m), it is possible to identify different 
species at pixel level. Unsupervised clustering gave certain 
recognition maps and these when compared with ground 
information (extensive ground truth is carried out) were found 
to be quite correctly depicting the type of vegetation zonation. 
This test was also carried out over a testsite near 
Bhairavavanipalem, an area just to the south of the study area. 
  
  
  
& Digitol (sup * 
Figure 2.3 
Figure 2.4 
[82 00"E T IT xx 027 30°8 1700'N 
| 8245 E Cite 
SUGGESTED OPTIMUM LANDUSE % MAP 
T5 10 7175 km, 
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1630 N 
2.7 GIS Modeling 
The various parameters obtained from Remote sensing and the 
other collateral data sources were integrated to develop an 
integrated optimum landuse plan using GIS. The various 
thematic maps like soils, geomorphology , slope, 
landuse/landcover were overlaid with each other digitally by 
assigning appropriate weightages to arrive optimum landuse 
plan. 
3.0 SUMMARY AND CONCLUSIONS 
The IRS -1B ,LISS II Imagery dated March,1995 is used for the 
preparation of landuse/landcover maps on 1:50,000 scale 
corresponding to Survey of India toposheets 65L/1,L/2,L/5 and 
L/6, the landuse/landcover maps are interpreted visually by 
following the legend prescribed by Department of space under 
National mission programme. Sequential nature of IRS data 
provide opportunity to monitor changes in the landuse activities 
in the mangroves. 
For a comparative analysis and change detection , the current 
landuse information with past .As such interpretation of data for 
the period February 1994 is carried out. It was observed that 
during a span of one year period , the spread of aquaculture has 
caused destruction of mangrove upto 22.69 Ha. per annum in 
area particularly in the I Polavaram mandal Region. This 
would have definite impact on the ecology of the area. 
It was observed that due to pressure of population , settlements 
have been established by clearing mangroves. Increasing use of 
pesticides, industrial pollution near by study area, the 
ecosystem has been changed completely. Many areas under 
forests were found have been converted into fishponds and salt 
beds. The corresponding map depicting changes was produced 
in the study. 
Table-3.1. . Shows the action items prepared from of optimum 
landuse plan. (Figure 2.4) 
  
  
Potential Area for 
Suggested optimal + Priority for 
Land Resource 
landuse development 
Development 
  
  
Cropland in Kharif/ Rabi season 
Intensive agriculture High priority 
Agro-horticulture 
Mangroves 
Regeneration, protection High priority 
and 
conservation of man- 
groves as a 
biosphere and 
wildlife 
reserve. 
Sandy area 
Development of shelterbelts High priority 
of 
plantations to protect 
from 
sea erosion. 
417