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Community structure and species diversity of Saddle Peak forests in Andaman Island

Authors:
  • Dolphin Institute of Bio-Medical & Natural Sciences, DEHRADOON, INDIA

Abstract

Saddle Peak forests, declared as a National Park, in Diglipur forest division of north Andaman (13°15′ to 13° 41′ N and 92° 37′ to 93° 7′ E) are characterized as humid tropical evergreen forests. A few species like Aglaia andamanica, Artocarpus gomeziana, Bombax insignie were common in all the studied sites. Among species, in littoral forests Mimusops littoralis, Artocarpus gomeziana, and in inland forest Pterocymbium tinctorium, Taberneamontana crispa, were dominant. In foothill forest Artocarpus chaplasa, Mallotus peltatus (male), were abundant whereas in middle saddle peak forest area Zanthoxylon budrunga, Parishia insignis and Mesua ferrea were the most abundant species. Across the sites the population density increased from 459 to 2681 plants per hectare from littoral to middle saddle peak forest site, but the reverse was true for basal area which decreased from 74 to 48 m2 ha-1. The species richness (61) as well as Shannon Wiener’s diversity index (3.58) were highest in foothill forest. Beta diversity was maximum in inland forest (5.1) and minimum in middle saddle peak forest (1.54). Heterogeneity was almost similar in foothill and middle saddle peak forests and it was relatively less in littoral forest zone. Mean girth showed a decreasing pattern from littoral forest (183) to middle saddle peak forest (39) similar to basal area. Size variation was greatest in foothill forest site showing a highest degree of asymmetry. Population structures for different forests have been prepared and interpreted.
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... Uniyal et al. (2010) reported Simpson's index of dominance to be 0.24 and 0.35 for managed and unmanaged forests respectively in Garhwal Himalaya. Tripathi et al. (2004) found Simpson's index of dominance for undisturbed forest between 0.041 to 0.126. This study also showed Simpson's index of dominance for the unmanaged block was 0.109 which is similar to the previous study however it was found higher for the managed blocks. ...
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Chapter
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Chapter
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