Phytosociological analysis of the restored Sal (Shorea robusta) plantations and natural sal forest of Tripura

Abstract

Among the existing activities in managing tropical forests, conservation efforts for Sal (Shorea robusta) forest in Tripura have virtually offered very valuable results. 68 plant species belonging to 41 taxonomic families were identified in such study areas. Remarkable dissimilarity between the stands of the restored coppice crop (7 and 16 years) and natural forest (approx. 45 years) was observed. Ground flora of young coppice crop was enriched with herb species while the density of shrubs and woody climbers was higher in the natural stand. Density per ha of herbs, shrubs and trees varied between 168000-497800, 18800-42112, 1100-2975 respectively. Total basal cover (m2 per ha) of herbs, shrubs and trees ranged between 0.524-0.941, 0.138-0.952, 2.333- 86.295 respectively. In the shrub layer 24.9% to 46.2% of the density and 53.4-81.6% of the Total Basal Cover (TBC) was shared by saplings belonging to economically and medicinally important tree species. It also indicates the regeneration potential of the area. Diversity index (Shannon Wiener Index) varied between 0.918- 0.967 for herbs, 0.743-0.876 for shrubs and 0.859 for trees. Values of Jaccard Similarity index were between 33-80% in herb layer, 22-48% in shrub layer, 14-100% in tree layer. The study brings out that the distribution of most of the species was random to contagious. Important flora viz. Smilax zeylanica, Vitex peduncularis, Ziziphus rugosa were the common species of the plant community on account of intact natural habitat.