PRESENT STATE AND FUTURE TRENDS OF PINE FORESTS OF MALAM JABBA, SWAT DISTRICT, PAKISTAN

摘要

Present state and future trend of pine forests of Malam Jabba, Swat district, Pakistan explored. We focused onvegetation composition, structure, diversity and forests dynamics. Thirteen stands were sampled by Point Centered Quartermethod. Among all stands four monospecific forests of Pinus wallichiana attained highest density ha-1 except in one standwhere Picea smithiana attained 401 trees ha-1. Unlike density, the basal area m2 ha-1 of these stands varies stand to stand.Based on floristic composition and importance value index, five different communities viz Pinus wallichiana-Piceasmithiana; Picea smithiana-Pinus wallichiana; Abies pindrow-Pinus wallichiana; Pinus wallichiana-Abies pindrow; Abiespindrow-Picea smithiana and 4 monospecific forests of Pinus wallichiana were recognized. Size class structure of forestsshowed marked influence of anthropogenic disturbance because not a single stand showed ideal regeneration pattern(inverse J shape distribution). Future of these forests is worst due to absence trees in small size classes. Gaps are alsoevident in most of the forest stands. Stand diversity, richness, equitability and Simpson’s dominance values formulated onsingle stand basis. Diversity of Abies pindrow and Pinus wallichiana stand was highest because these stand occupieddominant species, while lowest diversity observed in some Pinus wallichiana and Picea smithiana stand as these standshave mark difference between the dominance of two species. In the monospecific forests, the diversity level was zero,suggesting the monopolization of resources by one species or elimination of other tree species in these stands.