Phytosociological Studies on Arboreal Plant Species in Ramshehar Range of Nalagarh Forest Division, Himachal Pradesh, India

The present study was conducted in the Ramshehar range of the Nalagarh Forest Division to examine the variation in species composition, diversity, and structure of arboreal plant species along an altitudinal gradient. Field visits were conducted in the study area from March 2023 to September 2024. The Ramshehar range forests exhibit two forest types: Northern dry mixed deciduous forests (5B/C2) and Himalayan subtropical pine forests (9/C1a), spanning an altitudinal range from 450 m to 1200 m amsl. To analyse the arboreal vegetation composition, stratified random sampling was adopted. Various phytosociological and diversity indices have been used to get the vegetation composition of arboreal species in all three elevations. A total of 79 woody species, comprising 46 trees and 33 shrubs belonging to 35 families and 69 genera were recorded from the region. Fabaceae, Rubiaceae, Moraceae, and Lamiaceae were found to be the top 5 dominant families. Species exhibit significant composition and phytosociological attributes differences across the three elevation zones. The lower altitudinal zone (Zone I) showed the highest species diversity and richness for trees, while the middle altitudinal zone (Zone II) showed the highest species diversity and richness for shrubs, as indicated by various diversity indices. The density value ranges between 480 Individual ha-1 to 530 Individual ha-1 for trees and 5170 Individual ha-1 to 7320 Individual ha-1 for shrubs. Shannon Weiner Diversity Index value ranged between 1.97 to 2.80 for trees and 2.57 to 3.05 for shrubs. Simpson’s concentration of dominance values ranged between 0.10 to 0.29 for trees and 0.08 to 0.11.for shrubs The current study provides baseline information on the phytosociological diversity of arboreal plant species, aiding forest managers and policymakers in developing conservation strategies and also for the sustainable use of native species.