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Evaluating the change (1968-2001) in landscape pattern and analyzing disturbance in Baratang Forest Division (Andaman Islands), South East Asia
Results: In Baratang Islands the change is the vegetation cover in prominent on the western coast while southern and eastern coast has less human intrusion. A net decrease in primary forest cover (including evergreen, semi-evergreen, deciduous, mangrove, littoral and bamboo), which is attributable to increased population and consequent higher pressure on the forests, accounts to 2.34 per cent. Mangrove forest of the region is one of the most important coastal ecosystems. The status of mangrove forest in 1986 was 113.78 sq km while in 2002 it is analyzed as 112.27 sq km, which shows a very insignificant change (0.58 sq km of the area has been converted to degraded mangrove due to coastal activities and tidal fluctuations)(Table 1& Fig 2&3). The non-forest classes in the islands viz. settlements and agriculture has shown in increase in last two decades. The area under each type depicts that tropical moist deciduous forests occupy a large area at present compared to previous years. The total area under primary evergreen forest in 1986 was 129.9 4.sq km (22.36 %) whose status has reduced by 8.7 sq km (Table 2).  Fig 2: Vegetation cover derived in Baratang Island using two time period data  Fig 3 : Change in the vegetation cover is prominent on the western coast in Baratang Islands
It can also be inferred that the loss in primary forest can be compensated with the increase in secondary formations. Relatively more conversion of teak plantation into semi-naturalized deciduous forest was noticed in the central portion of the island. Havelock Island has undergone noticeable changes in last one and a half decade. The evergreen forest had undergone a decrease of 3.46 %. The mangrove forest area has reduced from a total of 12.51 sq km in 1986 to 11.77 sq. km in 2001. Neil Island has undergone outstanding changes in the evergreen forest cover. Extraction activities coupled with increasing population ahs led to the conversion of evergreen cover to semi-evergreen. At places encroached land has been completely cleared for expansion in agricultural activities (increase by 5.93 %). The littoral forest on the northern coast of the islands has also show slight decrease (0.15 sq km) (Table 3 ).
Change in primary forest (1968-2001): The analysis indicates that area has undergone crucial changes in the primary forest pattern. The plantation area showed remarkable increase between 1968 and 1986, but not much from 1986 to 2001. The scientific approach in management practices after 1970’s have emphasized on mangrove conservation and regeneration therefore the area of this eco-fragile formation shows stability in occurrence. It was also observed that evergreen and semi-evergreen forest had been major forest type in the region before the rise in settlement and agriculture activities. Due to progression in plantation practices large stretches for primary forest was cleared from between 1970 -1980, majority of it in the main Baratang island resulting in shrinkage of evergreen forest. Extraction activities for the fulfilment of timber requirement have created gaps leading to increment in the percentage of secondary forest in the region mostly after 1980’s.During the last four decades many fold increase in area under agriculture and settlements was observed (Table 4 & 5, Fig 4 & 5).  Fig 4 Change in primary forest and plantation pattern in Baratang islands
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