Pioneer community level syntaxonomy of forests of lesser Himalayan belt of upper Tanawal Mansehra, Pakistan

摘要

The present study is the first comprehensive investigation of forest communities of 127 stands in Upper Tanawal forests by quadrat method. Based on phytosociological analysis, the composition and distribution of tree species were described quantitatively on the basis of their IVI values using TWINSPAN classification. With the help of IVI values of tree species from 127 sampling station, TWINSPAN classified 20 tree communities. The occurrence of huge numbers of tree communities is due to restriction of single plant habit. Our investigation revealed that the diversity of trees species in this region decreases with increase in the elevation. Pinus wallichiana were observed the most dominant tree species at higher altitudinal areas. From 2 sampling sites, i.e. 2200 m and 2300 m of altitudes, pure coniferous community of Taxus-Abies-Pinus wallichiana was documented with only these three tree species. It was observed that the tree species like Picea smithiana, Abies pindrow, Rhododendron arboretum, Cedrus deodara, Taxus baccata and Quercus spp were rare in study area. All the tree communities as well as their associated biodiversity should be conserved and protected to ensure the future existence of these forest lands.