Species Diversity and Community Assembly of the Vegetation of Mankial Valley, District Swat

Background and Objective: Phytosociological studies explain and communicate the distribution of different plant communities with ecological factors in a particular zone, which give consequent results to scientific and practical proposals for improvement of the studied area. This study was designed to explore the species diversity, plant communities and relationship of different plant species with the environmental variables. Materials and Methods: The study area was surveyed to identify the different stands of vegetation based on habitats and physiognomy of vegetation by using the line transect method. The GPS and clinometer were used for recording the physiographic factors like slope exposure, angle of slope, elevation, latitude and longitude. Soil samples at 15 cm depth were collected from each stand and were analyzed for soil texture, water holding capacity, EC, N₂, P, K, Mg and Na. The TWINSPAN analysis was used to classify the vegetation into plant communities. Results: From 15 stands 153 plant species belonging to 110 genera and 56 families were recorded. The leading family was Asteraceae with 20 species. Therophytes were the dominant life-form with 41.45%, followed by Chamaephytes with 15.79%. The dominant leaf spectrum was microphylls with 32.24%. Two Way Indicator Species Analysis (TWINSPAN) classified the vegetation into 5 plant communities. Conclusion: It was perceived that mostly north-facing slopes have higher numbers of communities than south-facing slopes. There was a close relationship between physiographic factors and vegetation. Anthropogenic and biotic disturbances cause degradation of pastures and affect the natural biodiversity. Therefore, sustainable use of natural resources and conservation is necessary in order to preserve biodiversity for future use.