Pak. J. Bot ., 47(SI): 93-104, 2015. PHYTOGEOGRAPHIC ANALYSIS AND DIVERSITY OF GRASSES AND SEDGES ( POALES ) OF NORTHERN PAKISTAN ZAHID ULLAH 1* , MUSHTAQ AHMAD 2 HASSAN SHER 1, HAMAYUN SHAHEEN 3 AND SHUJAUL MULK KHAN 2* 1Center for Plant Sciences and Biodiversity, University of Swat, Pakistan 2Department of Plant Sciences, Quaid-i-Azam University, Islamabad, Pakistan 3Department of Botany, University of Azad Jammu and Kashmir, Pakistan *Corresponding author’s e-mail: [email protected], [email protected] Abstract The monocot order Poales is one of the largest (ca. 20,000 species), and economically and ecologically most important group of flowering plants. Exploring this important component of the biodiversity is of paramount significance in conservation of species and developing climate change models. Northern Pakistan occupies a unique biogeographic position at the summit of the planet’s three highest mountain ranges i.e.Himalaya, Hindukush and Karakurum.These ranges contain the hot spots of floral and faunal diversity with high proportions of endemic and rare species.The studies revealed 117 species belonging to 30 genera in three families of the order Poales . Juncaceae is represented by single genus Juncus with four species, Cyperaceae by 5 genera and 27 species, and Poaceae being the dominant family with 25 genera and 86 species. Carex and Poa are the largest genera having 21 and 16 species respectively. Phytogeographic analysis of the Poales of temperate and alpine regions of Northern Pakistan shows twelve different phytogeographic elements. The highest percentage of species (30%) belongs to the western Himalayan floristic region (near endemics), with cosmopolitan elements (19%), Central Asian elements (17%) and Eurasian elements (12%) being the other significant elements. The proportion of Endemic species (8%) is less apparent, while the rest of the seven categories are poorly represented. The Two Way Cluster Analysis (TWCA) divided the sixteen districts into two major groups, and four subgroups based on environmental gradients of altitude, latitude and longitude. TWCA classified the data matrix including 114 species into seven clusters based on presence/absence data and elevation from mean sea level. Species in each cluster can be attributed to similar habitat conditions and altitudinal ranges. Hence it is clear that climatic characters associated with each category control the species distribution pattern. Key Words: Phytogeography, Floristic elements, Diversity, Grasses, Sedges, Northern Pakistan Introduction Himalayan province and Tibetan province. The flora of Northern Pakistan has geographic affinities with Central Plant species are neither evenly nor randomly Asia, extending in the west from Turkey to the Gobi distributed on the surface of the earth, but rather in desert in the east. The western Himalaya is considered as definite geographic units, governed so by the physical the most species rich and dominant province with greater environment and climate (Qian, 2001). Factors affecting number of endemic taxa. This province represents a the spatial distribution of species include both abiotic and transition between the ancient Mediterranean and eastern biotic factors, such as soil, topography, geology, tectonic Asiatic floras. movements, mountain uplifting, climate change and There are several studies exist on the subject species evolution and migration. Analysis of the underpinning different regions of the globe. For instance, distribution patterns of plants (phytogeography) is Ocak et al., (2009) studied the floristic affinities and extremely valuable in perception of the ecological nature conservation status of wild Poaceae species from Malatya of a region and its plants wealth. Geographic analysis of province Turkey. The Irano-Turanian elements were plants is of utmost importance in tracing the origin of dominant with 28.7%, followed by Mediterranean and particular flora, its range of distribution, evolution and Euro-Siberian regions. Noroozi et al., (2008) analyzed the diversification. Floristic inventories and phytogeographic alpine flora of Iran that occur above 4000 m, and reported patterns of vegetation provide an understanding of plant 682 species in 39 families. They found that the flora of species diversity and management plans for their Iranian alpines is a transition of Anatolia, Caucasus and conservation (Harris et al., , 2012; Qian, 2001). Such the Hindu Kush, with a strong (58%) endemism. Dávila- studies are also very useful in the context of the global Aranda et al., (2004) discussed the distribution pattern of climate change and its biological impacts (Grabherr et Mexican endemic grasses. Garcia et al., (2009) compared al., , 1995; Körner, 2003; Wilson et al., 2007). distribution of 224 species of grasses of Brazilian Campos A useful approach for characterization of flora of a based on climate and geographic position. Haq et al., region and knowing its biogeographical affinities with (2011) studied the diversity and distribution pattern of flora of other regions is to classify its component taxa in cosmopolitan genus Carex L. from Kashmir Himalayas. to phytogeographic elements (Qian et al., , 2006; Stott, Ullah et al., (2013) studied the phylogeny of genus Carex 1981). Using this quantitative phytogeographic approach from Northern Pakistan and found its origin from central Takhtajan (1986) identified 5 floristic provinces in Asian elements. The distribution pattern and endemism of Pakistan. These are Sindian province, Southern Iranian family Crassulaceae from Pakistan and Kashmir were province, Northern Baluchistan province, Western investigated by (Sarwar & Qaiser, 2012) and concluded 94 ZAHID ULLAH ET AL ., that 15 taxa are of Irano-Turanian affinity, 16 are Sino- US, acronyms after (Holmgren et al ., 1990). Most of the Japanese elements and only one is Mediterranean information has been drawn from comprehensive literature element. Breckle (1974) evaluated phytogeographic (Chen et al ., 2006; Clayton et al ., 2006 onwards; Cope, pattern of the alpine and nival vegetation of Afghanistan 1982; Jafri, 1981; Kukkonen, 2001; Renvoize et al ., 2007; and stated that the flora has a close relationship with Simon et al ., 2011; Soreng et al ., 2009; Stewart, 1972; Central Asian plants. Tutin, 1993; Watson & Dalwitz, 1992). Information was There are few sporadic phytogeographic studies also extracted from the Royal Botanic Garden Edinburgh dealing with the flora of Northern areas of Pakistan. The Herbarium Catalogue, TROPICOS (Missouri Botanical high alpine region of Northern Pakistan is botanically and Garden), and Global Biodiversity Information Facility ecologically poorly investigated (Khan et al., 2013a & b). (GBIF) online databases. In comparison to the lowland areas there are still little in- depth studies, which deal with the alpine flora and Data analysis: Based on our results extracted from biodiversity (Shaheen et al. , 2011). No scientific study survey of detailed literature, monographs, floras and arise de novo. The major goal of this work is to provide a personal experience, a set of 11 floristic elements were detailed study of the grasses and sedges which are identified, as described in Table. 1. The description and distributed in the alpine and temperate region of Northern classification of floristic elements are based on (Brummitt Pakistan, with focus on distribution pattern and et al ., 2001). The map of Northern Pakistan (Fig. 1) phytogeographic relationship with the rest of the world. A illustrates the position and geographic coordinates of all second goal of the study is to analyze the endemism and the 16 districts included in the present study. These propose the origin of the flora of the region. districts includes 1) Ghanche, 2) Skardu, 3) Astore, 4) Diamer, 5) Hunza-Nagar, 6) Gilgit, 7) Ghizer, 8) Chitral, Material and Methods 9) Dir, 10) Swat, 11) Kohistan, 12) Mansehra, 13) Abbotabad 14) Neelum, 15) Muzaffarabad and 16) Bagh. Data gathering : The distribution pattern of species The presence/absence and elevation data for each belonging to the order Poales for Northern Pakistan (Fig. 1) species was recorded and arranged in EXCEL spreadsheets that occurs in the alpine and temperate region (2000 m, and analyzed. The analyses were done through multivariate a.s.l) is based primarily on the extensive field excursions statistics in PC-ORD version 5 (McCune & Mefford, between 2008 and 2013. The species were studied in their 1999). In order to find out the pattern of distribution of natural habitats, and geographic coordinates, altitudes, species along the altitudinal gradient Two Way Cluster habitat type and aspect of occurrence were recorded for analysis (TWCA) using Sorensen measures was each species. In addition to this, information on species subsequently applied to the data (Greig-Smith, 2010). The distribution were extracted from the specimens housed in cluster analysis, group similar entities together in a single the following herbaria: ISL, E, K, BM, KUH, RAW and cluster and result in a dendrogram. Fig. 1. (A) Reference map of Pakistan (B) Map of Northern Pakistan, showing location of the representative districts with geographic coordinates. PHYTOGEOGRAPHIC ANALYSIS OF THE GRASSES AND SEDGES 95 Table. 1. Definitions of floristic elements. No. Floristic Element Distribution 1 Cosmopolitan These are species with worldwide distribution on all or almost all continents. Occurring in and around the tropical and subtropical regions of the world, some taxa may 2 Pantropical