Pak. J. Bot., 44: 113-122, Special Issue May 2012. VEGETATION COMPOSITION AND THREATS TO THE MONTANE TEMPERATE FOREST ECOSYSTEM OF QALAGAI HILLS, SWAT, KHYBER PAKHTUNKHWA, PAKISTAN MOHAMMAD ILYAS 1,* , ZABTA KHAN SHINWARI 2 AND RAHMATULLAH QURESHI 1 1 Department of Botany, Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi. 2 Department of Biotechnology, Quaid-i-Azam University, Islamabad *Corresponding author e-mail: botanist_jcs@yahoo.com Abstract The remnant temperate forests in Qalagai hills, district Swat, Khyber Pakhtunkhwa is under severe anthropogenic pressure in the form of logging, deforestation, over-grazing and clearance of forest for terrace cultivation. The present endeavours were undertaken to assess the structure and composition of the existing vegetation of the area with an aim to pinpoint strategies for the conservation of this threatened ecosystem. A total of 160 stands were sampled by using 10x10m, 2x2m and 1x1m quadrats for tree, shrub and herb layers, respectively adapting random stratified design. Frequency, density and crown coverage of each species were recorded and converted to relative values to obtain importance values. In all, floristic composition comprised of 209 species of vascular plants belonging to 167 genera and 75 families. On the basis of highest importance values, similarity index, topography, physiognomy and edaphic factors, eight stratified plant communities viz., 1) Populus-Debregeasia- Nasturtium, 2) Olea-Plectranthus-Micromeria, 3) Pinus roxburghii-Plectranthus-Rumex, 4) Quercus-Indigofera-Amaranthus, 5) Pinus wallichiana-Indigofera-Galium, 6) Cedrus-Indigofera-Thymus, 7) Cedrus-Viburnum-Pteridium and 8) Pinus wallichiana-Viburnum-Leucas were established in the area. Reclamation and conservation of original ecosystem need a long term strategy with active involvement of the local inhabitants. Introduction Globally, every third plant species is hosted by the mountainous regions (Namgail et al., 2012). Forest ecosystems cover almost 5.01% of the land in Pakistan, which is far beyond the international standard on a per capita basis. The natural forest cover is decreasing at a rate of 0.75% annually (Anon., 2009). Montane temperate forests in Pakistan are predominantly coniferous nature with some broad leaved species (Hussain & Ilahi, 1991). The structure, composition and function of forest ecosystem change in response to climatic, topographic, edaphic and anthropogenic influences (Timilisina et al., 2007; Ahmed et al., 2010; Shaheen et al., 2011; Namgail et al., 2012). Like other forest types temperate forests are experiencing severe anthropogenic pressure (Ahmad et al., 2006; 2008; Singh et al., 2008; Shaheen et al., 2011). Deforestation, logging, overgrazing and clearing of land for terrace cultivation are the major threats responsible for the overall degradation of these forests (Hussain et al., 1997; Sher et al., 2010; Ahmad et al., 2010; 2011). The coniferous forests in the northern mountain regions particularly are under the heavy social and economic pressure of tree felling (Siddiqui et al., 1999). The vegetation of Swat and adjoining areas is a mosaic of different community types and has been studied sporadically (Beg & Khan, 1984; Hussain et al., 1992; Hussain et al., 1995; Sher & Al-Yameni, 2010; Ahmad et al., 2010; Rashid et al., 2011; Khan, 2012). Qalagai hills are situated in the North West of District Swat at a distance of about 30 km from Saidu Sharif. The area lies between latitude 34 º 51′ to 34 º 55′ North and longitude72 0 05′ to 72 0 10′ East in Swat district. The average elevation of the area varies from 1450 m to 2892 m from the mean sea level. The site is a part of Hindu Kush mountain range (Ahmed & Siraj ud Din, 1996). The hills are zigzag in shape forming different ridges and furrows, which face differently to the incident light. Geologically the hills are of recent origin and forms part of the southern stretch of Kohistan Island arc, which is delineated on the South from the northern tip of the Indian plate marginal mass by a Himalayan megashear called the Main mantle thrust, the southern suture (Tahirkheli, 1982). Climatically the area falls within the subtropical zone but due to variation in the topography, altitude, aspect and vegetation cover the climate gradually change into montane temperate zone. The natural vegetation of Qalagai hills can be classified as: montane subtropical forest at lower altitudes and montane temperate forests at higher altitudes (Champion et al., 1965; Beg, 1975). The area was recently hit by a worst type of religious extremism, in which alongside other sectors of society the forest resources were badly affected (Sharar, 2009). Considering the augmented pressure and threat to ecology and biodiversity of Qalagai hills, the present study was undertaken to provide baseline information on the community structure, species diversity and governing factors thereof, for proper conservation measures of the existing vegetation in the area. Materials and Methods The study was conducted in summer seasons (May- September) of 2007-2009. The area was divided into different zones on the basis of physiognomy, altitude, aspect and topography. Random stratified design was used for vegetation survey of the area. Soil was collected form at least three randomly selected areas in each site up to a depth of 15cm and thoroughly mixed to make a composite mix. The soils were analyzed for texture, pH, and percentage of calcium carbonate, organic matter, phosphorus, potassium and nitrogen using methods described in Hussain (1989), Jackson (1962) and Haluschak (2006). Quadrat method of vegetation sampling (Hussain 1989) was used to analysis the vegetation of Qalagai hills. The size of quadrants were 1x1 (1 m 2 ) for herbs, 2 x 2 (4 m 2 ) for shrub layer and 10 x 10 (100 m 2 ) for trees determined by species area curve as explained by Cox (1967). Twenty quadrants each were laid randomly in each