Nature and Science, 2011;9(12) http://www.sciencepub.net/nature Species Diversity and Community Structure of a Temperate Mixed Rhododendron Forest along an Altitudinal Gradient in West Siang District of Arunachal Pradesh, India Sanjeeb Bharali 1, Ashish Paul 2, Mohamed Latif Khan 3, Lal Bihari Singha 4, * * Department of Forestry, North Eastern Regional Institute of Science & Technology, (Deemed University), Nirjuli – 791109 (Itanagar), Arunachal Pradesh, India. E-mail-
[email protected], Phone No. (+91) 9436094198 ** Department of Forestry, North Eastern Regional Institute of Science & Technology, (Deemed University), Nirjuli – 791109 (Itanagar), Arunachal Pradesh, India. E-mail-
[email protected], Phone No. (+91) 9862035885 *** Department of Forestry, North Eastern Regional Institute of Science & Technology, (Deemed University), Nirjuli – 791109 (Itanagar), Arunachal Pradesh, India. E-mail-
[email protected], Phone No. (+91) 9425280739 **** Department of Forestry, North Eastern Regional Institute of Science & Technology, (Deemed University), Nirjuli – 791109 (Itanagar), Arunachal Pradesh, India. E-mail-
[email protected]. Phone No. (+91) 9436228916 Abstract: Species diversity and community structure of a Rhododendron forest along an altitudinal gradient was studied through quadrat method and all important community parameters were worked out using standard procedures. A total of 72 species representing 58 genera belonging to 35 families were recorded from the three study stands at different altitudes. The species richness index of tree and shrub species was highest in Hanuman Camp (mid altitude) while, for herb it was highest in Shegong (lower altitude). The richness index of tree species shows a positive relation while, the shrub and herb species have a negative relation with the altitudinal gradient. Hanuman Camp has highest tree species richness, tree density (individual ha-1) and basal area (m2 ha–1) with Rhododendron grande as the dominant tree species.