Kadar Abu dan pH Kulit Kayu Acacia mangium Willd. Generasi Ketiga sebagai Parameter Energi Baru Terbarukan di KHDTK Alas Kethu

Herlambang Arief Saputra, Masendra, S.Hut., M. Agr., Ph.D.

2026 | Tugas Akhir | D4 PENGELOLAAN HUTAN

Kulit kayu Acacia mangium merupakan hasil samping industri kehutanan yang berpotensi dimanfaatkan sebagai bahan baku biomassa energi terbarukan. Akan tetapi, informasi mengenai karakteristik kadar abu dan nilai pH kulit kayu serta potensi genetiknya sebagai dasar seleksi dalam program pemuliaan A. mangium masih terbatas. Penelitian ini bertujuan mengevaluasi karakteristik, kadar abu, dan nilai pH kulit kayu A.mangium generasi ketiga di KHDTK Alas Kethu, mengestimasi parameter genetik, serta mengintegrasikan karakter pertumbuhan dan karakteristik biomassa sebagai dasar seleksi famili. Penelitian dilakukan pada 20 famili half-sib hasil penyerbukan terbuka berumur 10 tahun di KHDTK Alas Kethu, Wonogiri, Jawa Tengah. Data dianalisis menggunakan model linier efek campuran (linear mixed-effects model), dilanjutkan dengan analisis heritabilitas, korelasi genetik dan fenotipik, Principal Component Analysis (PCA), serta analisis klaster. Hasil penelitian menunjukkan bahwa kadar abu berkisar 2,18–2,98?n telah memenuhi persyaratan SNI 8675:2018 (?5%), sedangkan nilai pH berkisar 4,65–5,26 yang menunjukkan karakter biomassa bersifat asam lemah. Karakter kadar abu memiliki heritabilitas sedang (h² = 0,424), sedangkan nilai pH memiliki heritabilitas rendah (h² = 0,283). Analisis PCA dan analisis klaster mengelompokkan 20 famili ke dalam tiga kelompok utama. Berdasarkan integrasi hasil heritabilitas, korelasi genetik dan fenotipik, PCA, serta analisis klaster, Grup II (Famili 5 dan 9) direkomendasikan sebagai materi genetik potensial sebagai sumber bahan biomassa untuk energi pada program pemuliaan A. mangium generasi berikutnya.

Acacia mangium bark is a byproduct of the forestry industry with the potential to be used as a raw material for renewable energy biomass. However, information regarding the ash content and pH of the bark, as well as their genetic potential as a basis for selection in breeding programs of A. mangium, remains limited. This study aims to evaluate the characteristics, ash content, and pH of the third-generation A. mangium bark, estimate genetic parameters, and integrate growth traits and biomass characteristics as a basis for family selection. The study was conducted on 20 half-sib families resulting from open pollination, aged 10 years, at the Alas Kethu Forest Research and Development Center (KHDTK), Wonogiri, Central Java. The data were analyzed using a linear mixed-effects model, followed by analyses of heritability, genetic and phenotypic correlations, Principal Component Analysis (PCA), and cluster analysis. The results showed that ash content ranged from 2.18–2.98% and met the requirements of National Indonesia Standard (SNI) No. 8675:2018 (?5%), while pH values ranged from 4.65–5.26, indicating that the biomass was slightly acidic. Ash content exhibited moderate heritability (h² = 0.424), while pH exhibited low heritability (h² = 0.283). PCA and cluster analysis grouped the 20 families into three main clusters. Based on the integration of heritability results, genetic and phenotypic correlations, PCA, and cluster analysis,  Group II (Families 5 and 9) were recommended as potential genetic materials because they possess a combination of growth traits and biomass characteristics for energy that support the next-generation A. mangium breeding program.

Kata Kunci : Acacia mangium, kadar abu, pH, biomassa, generasi ketiga, pemuliaan pohon, famili.