Assessment and monitoring of deforestation and land-use changes (1976-2014) in Andaman and Nicobar Islands, India using remote sensing and GIS

摘要

Andaman and Nicobar Islands are part of Indo-Burma and Sundaland global biodiversity hotspots. This study provides spatial information on forest types, deforestation and associated land-use changes in Andaman and Nicobar Islands during 1976 to 2014. Satellite remote sensing and geographical information system (GIS) techniques have been used to analyse forest cover changes, rate of deforestation and to map patterns of forest cover distribution in Andaman and Nicobar Islands. Classified maps prepared for 1976, 1989, 1993, 2000, 2006 and 2014 indicate that the forest cover accounts for an area of 7086.1 (85.9%), 6969.2 (84.5%), 6941.1 (84.1%), 6934.6 (84.1%), 6617.8 (80.2%) and 6407.3 sq. km (77.7%) respectively. It was found that the area occupied by evergreen forests is very high, consisting of 3065.1 sq. km (32.2%) followed by semi-evergreen (1531.6 sq. km), moist deciduous (1133.4 sq. km) and mangrove forest (677.2 sq. km) in 2014. There is large-scale deforestation in Andaman and Nicobar Islands which has been estimated as 678.8 sq. km during the last four decades. The loss of forest cover is high in moist deciduous forests which has been estimated as 312.2 sq. km in Andaman Islands; whereas in Nicobar Islands, the highest loss was found in evergreen forests (244.6 sq. km). The rate of deforestation in Andaman and Nicobar Islands was high during 2000-2006 (0.78) indicating major influence of the tsunami of 26 December 2004. The annual rate of deforestation from 2006 to 2014 was 0.40. The geospatial analysis of areas of forest cover change provides baseline information for restoration and conservation planning.