Impact of tsunami on the forest and biodiversity richness in Nicobar Islands (Andaman and Nicobar Islands), India

Occurrences of extreme events are likely to cause major decline in global biodiversity. In one such event, on December 26, 2004 tsunami caused extensive damage and irreparable losses to the ecology and biodiversity of low-lying areas of the countries located around the Indian Ocean region. Archipelago of Andaman and Nicobar Islands, one of the richest centre of endemism and biodiversity in the Indo-Malayan region, suffered great loss of forests and coastal biodiversity owing to its closeness to the epicenter of tsunami, i.e. just off the coast of Indonesia. There is little insight into the resilience and rate of recovery pattern of tropical coastal habitats consequent to catastrophic impacts of tsunami. It’s important to study the impacts of tsunami on the forest and biodiversity in order to suggest mitigation, restoration measures and long-term conservation planning. Here we have assessed the immediate after-effects of December 26, 2004 tsunami on the forests and areas prioritized for biodiversity conservation analyzing pre and post tsunami satellite imageries. The effect of topographic patterns of Island’s coastal areas and their distance from the epicenter of tsunami with respect to changes in the forests and different levels of biologically rich areas modeled for prioritization for different groups of Islands in Nicobar has been studied. Great Nicobar accounted for higher proportion of total forest area damaged and submerged in Nicobar, followed by Central Nicobar and Car Nicobar. Mangroves, littoral forest, beach forest and low land swamps and Syzygium swamps were most affected. Study brings out spatially explicit scenario of damaged, submerged and lost forest areas and corresponding area statistics, vital for understanding and mitigating medium and long term effects of tsunami an extreme event.