Abstract
Hutan adat memiliki peranan penting dalam menjaga keseimbangan ekosistem serta mendukung keberlanjutan sosial budaya masyarakat lokal. Hutan Adat Montong Gedeng di Desa Loloan, Kecamatan Bayan, Kabupaten Lombok Utara merupakan salah satu kawasan hutan adat yang dimanfaatkan masyarakat untuk kebutuhan adat, ritual budaya, dan pelestarian lingkungan. Namun, informasi mengenai struktur dan komposisi vegetasi pada kawasan tersebut masih terbatas. Penelitian ini bertujuan untuk menganalisis struktur dan komposisi vegetasi, dominansi spesies, indeks ekologi vegetasi, serta pola distribusi spesies pada Hutan Adat Montong Gedeng. Penelitian dilaksanakan pada Januari–Februari 2025 menggunakan metode systematic sampling with random start dengan intensitas sampling 1% dari total luas kawasan hutan 84 ha sehingga diperoleh 21 plot pengamatan berukuran 20 × 20 m. Hasil penelitian menunjukkan bahwa vegetasi Hutan Adat Montong Gedeng terdiri atas 13 famili, 16 spesies, dan 447 individu. Spesies yang mendominasi adalah Schleichera oleosa dengan jumlah individu sebanyak 161 dan nilai Indeks Nilai Penting (INP) tertinggi sebesar 68,57%, diikuti Schoutenia ovata sebesar 48,64%. Struktur vegetasi didominasi oleh kelas tinggi 6–10 m dan kelas diameter 1–75 cm. Nilai indeks keanekaragaman Shannon-Wiener tergolong rendah hingga sedang (0,69–0,84), indeks kekayaan jenis tergolong sedang (0,76–1,14), dan indeks kemerataan tergolong rendah (0,06–0,10). Pola distribusi frekuensi spesies berdasarkan hukum Raunkiaer menunjukkan pola A > B > C yang mengindikasikan adanya kecenderungan distribusi spesies yang relatif teratur pada komunitas vegetasi. Penelitian ini menyediakan informasi dasar ekologis mengenai kondisi vegetasi Hutan Adat Montong Gedeng yang dapat digunakan sebagai dasar pengelolaan dan konservasi hutan adat berbasis masyarakat. Vegetation Structure and Composition in Montong Gedeng Customary Forest, Loloan Village, Bayan District, North Lombok Abstract Customary forests play an important role in maintaining ecosystem balance and supporting the socio-cultural sustainability of local communities. Montong Gedeng Customary Forest in Loloan Village, Bayan District, North Lombok Regency is one of the customary forest areas utilized by the community for traditional purposes, cultural rituals, and environmental conservation. However, information regarding the vegetation structure and composition of this area is still limited. This study aimed to analyze the vegetation structure and composition, species dominance, vegetation ecological indices, and species distribution patterns in the Montong Gedeng Customary Forest. The study was conducted from January to February 2025 using a systematic sampling with random start method with a sampling intensity of 1% of the total forest area of 84 ha, resulting in 21 observation plots measuring 20 × 20 m. The results showed that the vegetation of Montong Gedeng Customary Forest consisted of 13 families, 16 species, and 447 individuals. The dominant species was Schleichera oleosa with 161 individuals and the highest Important Value Index (IVI) of 68.57%, followed by Schoutenia ovata with 48.64%. The vegetation structure was dominated by height classes of 6–10 m and diameter classes of 1–75 cm. The Shannon-Wiener diversity index was categorized as low to moderate (0.69–0.84), species richness index was moderate (0.76–1.14), and evenness index was low (0.06–0.10). The species frequency distribution pattern based on Raunkiaer’s law showed an A > B > C pattern, indicating a relatively regular tendency of species distribution within the vegetation community. This study provides baseline ecological information regarding the vegetation condition of Montong Gedeng Customary Forest that can support community-based customary forest management and conservation efforts.