PROS SEM NAS MASY BIODIV INDON Volume 1, Nomor 3, Juni 2015 ISSN: 2407-8050 Halaman: 428-433 DOI: 10.13057/psnmbi/m010308 Exploration, collection, and conservation of dipterocarps in Riau Islands Eksplorasi, koleksi dan konservasi jenis-jenis dipterokarpa di wilayah Riau Kepulauan ATOK SUBIAKTO 1,♥ , HENTI HENDALASTUTI RACHMAT 2,♥♥ 1 Pusat Penelitian dan Pengembangan Konservasi dan Rehabilitasi, Badan Litbang Kehutanan, Kementerian Kehutanan dan Lingkungan Hidup. Jl. Gunung Batu No. 5. PO Box 165, Bogor 16001, Jawa Barat. Tel. +62-251-8633234; 7520067. Fax. +62-251 8638111. email: atoksubiakto@yahoo.com 2 Balai Penelitian Teknologi Serat Tanaman Hutan, Kotak Pos 04/BKN Bangkinang 28401, Riau, Tel. +627627000121,Fax. 0762-21370;  email: hendalastuti@yahoo.co.uk Manuskrip diterima: 11 Februari 2015. Revisi disetujui: 30 April 2015. Subiakto A, Rachmat HH. 2015. Eksplorasi, koleksi dan konservasi jenis-jenis dipterokarpa di wilayah Kepulauan Riau. Pros Sem Nas Masy Biodiv Indon 1: 428-433. Kekayaan dan keragaman jenis-jenis dipterokarpa di daratan Sumatera sudah terdokumentasi dengan baik dan dikenal di seluruh dunia. Namun demikian, keberadaan dan kekayaan jenis dipterokarpa pada rentetan pulau-pulau kecil sisi timur daratan Sumatera yang berbatasan dengan Negara tetangga Malaysia dan Singapura belum tergali secara optimal, padahal dari segi phyllogeography keberadaan jenis-jenis dimaksud pada pulau-pulau tersebut akan sangat menarik terutama dalam menggali sejarah evolusi dan penyebaran. Penelitian ini bertujuan untuk mencatat jenis-jenis dipterokarpa yang tumbuh di masing-masing lokasi dan mengumpulkan materi genetik tumbuhan dari lokasi tersebut untuk dikembangkan di persemaian sebagai upaya koleksi dan pelestarian jenis-jenis dipterokarpa secara ex situ. Kegiatan eksplorasi dilakukan di wilayah Kepulauan Riau mencakup P. Lingga, P. Singkep, P. Bintan, P. Batam dan P. Bunguran (Kep. Natuna). Dari hasil eksplorasi tersebut tercatat jumlah jenis dipterokarpa yang ditemukan untuk masing-masing pulau adalah 13 jenis di P. Lingga, 2 jenis di P. Singkep, 7 jenis di P. Batam, 10 jenis di P. Bintan, dan 21 jenis di P. Bunguran-Kepulauan Natuna. Jumlah material genetik berupa anakan alam yang terkoleksi bervariasi untuk setiap pulau, masing- masing berturut turut untuk Pulau Lingga, Bintan, Batam dan Bunguran-Kepulauan Natuna adalah 5900, 329, 25, 160. Anakan alam diperlakukan di dalam sungkup berkelembapan tinggi dan memakai naungan yang selanjutnya pemberian naungan dikurangi secara bertahap setelah hari ke-90. Kata kunci: Eksplorasi, konservasi, dipterokarpa, Riau kepulauan Subiakto A, Rachmat HH. 2015. Exploration, collection and conservation of dipterocarps in Riau Islands. Pros Sem Nas Masy Biodiv Indon 1: 428-433. The diversity and richness of dipterocarps in Sumatera mainland have been well documented and known throughout the world. On the other hand, the existence and the diversity of dipterocarps in small islands along the eastern part of Sumatera mainland, which is directly bordered with neighboring countries of Malaysia and Singapore have not been thoroughly studied. Phyllogeography of dipterocarps species from small islands particularly in the eastern part of Sumatra region is important information to reveal evolution history and their distribution. The aim of this research was to record the dipterocarps species growing naturally at each islands surrounding eastern part of Sumatra mainland and to collect genetic materials for preservation and ex situ conservation effort. Exploration was carried out in the island of Lingga, Singkep, Bintan, Batam, and Bunguran (Naturan Islands). Total number of the species found for each of the island was as follow: Lingga 13 species, Singkep 2 species, Batam 7 species, Bintan 10 species, and Bunguran 21 species. Number of genetic materials taken for each of the island was 5900, 329, 25, 160 consecutively for the island of Lingga, Bintan, Batam and Bunguran. Wildings were kept and treated in shaded-high humidity nursery chamber and after 90 days of care the shading was gradually decreased. Kata kunci: Exploration, conservation, dipterocarps, Riau Islands INTRODUCTION The tropical rainforests in Southeast Asia are characterized by a high species diversity of trees (Whitmore 1984). Dipterocarpaceae is a tree family with more than 450 species in 13 genera in Asia (Ashton 1982; Londoño et al. 1995; Morton 1995). They confine to tropical climates with a mean annual rainfall exceeding 1000 mm and/or dry season of less than six months. They usually grow in mixed stands (Ashton 1988). The highest species diversity of dipterocarps is observed in evergreen rainforests in Peninsular Malaysia, Sumatera and Borneo (Ashton 1982; Symington 1943; Whitten et al. 1987). In particular, Borneo is the main center of dipterocarps with the highest number of endemic species (155 species). Many different species of dipterocarps can be found on entirely different soil types and in nearly all of the different forest types of Southeast Asia (Lamprecht 1989). Based on the observation of herbarium collection in Herbarium Bogoriense (Purwaningsih 2004), in Indonesia most