Abstract
The present study highlights the community diversity and dominance spectrum of species in four abandoned shifting cultivation fallows in Karbi Anglong (Assam) of north-east India. In the study area 51 species belonging to 24 families were recorded as a component of fallow lands. Lantana camara and Chromolaena odorata showed their dominance in 5 and 10 years fallow with highest Importance Value Index (136.52 and 33.37 in 5 years, 18.97 and 53.52 in 10 years fallow, respectively). Gradual elimination of Imperata cylindrica from higher age fallows was noticed. Bamboo species, Dendrocalamus hamiltonii and Melocanna baccifera expressed their dominance in 15 to 20 years fallows. The fallow vegetation was replaced by shade intolerant broad-leaved species like Actinodaphne obovata, Artocarpus spp., Callicarpa arborea, Dysoxylum procerum, Erythrina stricta etc. during 10 to 20 years period as a form of secondary forest. Species diversity increased from 5 years fallow onward with maximum in 15 years fallow and declined later on. The highest similarity was observed in the fallow pair of 15-20 years.
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