24 | Bajpai et al.

The study highlights the association pattern of tree species in Katerniaghat Wildlife Sanctuary (KWS) a tropical moist deciduous forest of Terai region of Uttar Pradesh, India. In the present study the ecological exploration has been done to dig out the current statuse of the forest types in the sanctuary area. The cluster and PCA analyses grouped the forests of KWS into three major forest types: sal forest, miscellaneous forest and teak plantation. The different forest type exhibit differences in tree dominance and diversity: sal forest is dominated by Shorea robusta, miscellaneous forest by Mallotus philippensis and teak plantation by Tectona grandis. The tree species richness has been found 48.07 species ha-1 in teak plantation, 52.63 in miscellaneous forest and 55.35 in sal forest. The tree density has been found 769.23 stem ha-1 in teak plantation, 742.86 in sal forest and 671.05 in miscellaneous forest. The basal cover was observed 1260.75 m2 h-1 in miscellaneous forest, 3533.61 in sal forest and 4933.97 in teak plantation. The diversity indexes (Shannon & Fisher-alpha) have been found maximum (2.666 & 12.390) in miscellaneous forest, moderate (2.152 & 8.677) in sal forest and low (1.134 & 6.482) in teak plantation. The species heterogeneity has been found maximum (0.862) in miscellaneous forest, moderate (0.785) in sal forest and minimum (0.399) in teak plantation. The tree species richness and the basal area hav