Struktur Lamun di Zona Intertidal Kecamatan Tabukan Selatan, Kabupaten Kepulauan Sangihe, Sulawesi Utara (Structure of Seagrass on Intertidal Zone of Southern Tabukan Sub-District, Sangihe Islands District, North Sulawesi)
Authors: Tumadang Stevi , Siahaan Ratna , Maabuat Pience 
Published: July 2019

Struktur Lamun di Zona Intertidal Kecamatan Tabukan Selatan, Kabupaten Kepulauan  Sangihe, Sulawesi Utara(Structure of Seagrass on Intertidal Zone of Southern Tabukan Sub-District, Sangihe Islands District, North Sulawesi) Stevi Tumadang1), Ratna Siahaan1*) , Pience V. Maabuat1*) 1) Jurusan Biologi, Fakultas Matematika dan Ilmu Pengetahuan Alam, Universitas Sam Ratulangi – Manado 95115*Email korespondensi:ratnasiahaan@unsrat.ac.id Diterima 1 Juli  2019, diterima untuk dipublikasi 5  Agustus 2019 Abstrak  Lamun memiliki fungsi ekologis dan nilai ekonomi yang penting. Penelitian berujuan untuk menganalisis struktur lamun di tiga area intertidal yaitu Pantai Karurung (Desa Salurang), Pantai Palareng (Desa Palareng), dan Pantai Galogong (Desa Batuwingkung), Kecamatan Tabukan Selatan, Kabupaten Kepulauan Sangihe, Sulawesi Utara. Metode purposive sampling digunakan dalam penentuan tempat sampling dengan pengambilan sampel yang menggunakan metode line transect. Jenis-jenis lamun yang ditemukan sebanyak tujuh (7) jenis yaitu Cymodocea rotundata, Cymodocea serrulata, Enhalus  acoroides, Halodule uninervis, Halophila ovalis, Syringodium isoetifolium, dan Thalassodendron ciliatum. Lamun S. isoetifolium memiliki nilai Kepadatan Relatif tertinggi di ketiga stasiun berturut-turut, yaitu 48,60%, 43,31%, dan 44,08%. Secara berturut-turut, lamun S. isoetifolium juga memiliki Indeks Nilai Penting tertinggi di ketiga stasiun, yaitu 74,92%, 65,31%, dan 70,75%. Keanekaragaman jenis lamun pada ketiga stasiun tergolong sedang dengan Indeks Keanakeragaman Shannon-Wiener (H’) secara berturut-turut, yaitu 1,52; 1,61; dan 1,23. Secara keseluruhan, keanekaragaman jenis lamun di Kecamatan Tabukan Selatan tergolong sedang (H’:1,59). Kata kunci  :    struktur lamun, Tabukan Selatan, Pantai Karurung, Pantai Palareng, Pantai Galoghong, Kepulauan Sangihe Abstract Seagrasses have important ecological functions and economic values. The study was carried out to analyze structure and distribution of seagrass on three intertidal areas, i.e. Karurung Beach (Salurang Village), Palareng Beach (Palareng Village), and Galogong Beach (Batuwingkung Village), South Tabukan District, Sangihe Islands Regency, North Sulawesi. The purposive sampling method was applied in choosing sampling locations. The line transect method was used for sampling seagrass. Seagrass species found were seven (7) species, i.e. Cymodocea rotundata, Cymodocea serrulata, Enhalus acoroides, Halodule uninervis, Halophila ovalis, Syringodium isoetifolium, and Thalassodendron ciliatum. Seagrass S. isoetifolium had the highest Relative Density Value in three locations, i.e. 48.60%, 43.31%, and 44.08% perspectively. The seagrass S. isoetifolium also had the highest Important Value Index i.e. 74.92%, 65.31%, and 70.75% perspectively. The diversity of seagrass species in three stations was classified into moderate with Shannon-Wiener Biodiversity Index (H ') i.e. 1.52; 1.61; and 1.23 perspectively. The overall H’ of seagrass of South Tabukan was classified into moderate (H ': 1.59). Key words:      seagrass structure, South Tabukan, Karurung Beach, Palareng Beach, Galoghong Beach, Sangihe Islands