POTENSI BIOMASSA, KARBON DAN SERAPAN GAS CO2 JENIS GAMAL (Gliricidia sepium) BAGIAN ABOVE GROUND DI HUTAN PENDIDIKAN WANAGAMA I, YOGYAKARTA

Andreas Budi Rahutomo, Dr. Ir. Ris Hadi Purwanto, M.Agr.Sc.

2011 | Skripsi | S1 KEHUTANAN

Gamal ( Gliricidia sepium) merupakan spesies tumbuhan yang memiliki banyak kegunaan sehingga dikenal sebagai multipurpose tree species. Namun demikian, potensi gamal secara kuantitatif dalam menyimpan karbon belum banyak diketahui. Penelitian ini bertujuan untuk (1) Mengetahui kandungan biomassa dan karbon bagian above ground jenis jenis Garn.al (Gliricidia sepium)di Hutan Pendidikan Wanagama I, (2) menentukanmodel pendugabiomassa dan karbon untuk jenis pohon Gamal (Gliricidia sepium), (3) mengetahui potensi Garn.al (Gliricidia sepium) di Hutan Pendidikan Wanagama I dalam menyimpan biomassa dan karbon, dan ( 4) mengetahui potensi serapan gas CO2 pada spesies Gamal (Gliricidia sepium) bagian above ground ( atasan). Lima belas batang gamal dengan variasi diameter dari 1-15 cm ditebang sebagai sampel untuk membuat model penduga biomassa, karbon dan serapan gas CO2 bagian atasan. Pengambilan sampel ini dilakukan di petak 5 dengan umur penanaman 34 tahun. Kandungan biomassa dihitung dengan cara mengeringkan sampel batang dan cabang pada suhu 103±2°C serta daun pada suhu 60±2°C hingga mencapai berat kering konstan. Kandungan karbon diperoleh dengan analisis spektrofotometri, sedangkan serapan gas CO2 diperoleh dengan rumus perbandingan massa atom. Kandungan biomassa rata-rata pada pohon gamal sampel bagian atasan adalah sebagai berikut: organ batang 23,24 kg, organ cabang 12,65 kg, dan organ daun 0,29 kg/pohon, sedangkan rata-rata kandungan karbonnya adalah organ batang 11,06 kg, organ cabang 5,74 kg, dan organ daun 0,12 kg/pohon. Model penduga biomassa dan karbon gamal bagian atasan adalal1 sebagai berikut: biomassa Bt = 0,084(D)2-638 (R2 = 0,924), karbon Ct = 0,036(D/'672 (R2 = 0,924). Potensi biomassa dan karbon gamal bagian atasan di Wanagama I adalah sebagai berikut: biomassa Cio,95 = 82,513 ± 3,075 ton/ha, karbon Clo,95 = 38,430 ± 1,574 ton/ha. Potensi serapan gas CO2 gamal bagian atasan di Wanagama I adalah Clo.9s = 140,909 ± 8,617 ton/ha.

Gliricidia sepium is a tree species which has many function so that itis known as multipurpose tree species. However, the potential of G. sepium quantitatively in terms of carbon storage has not yet been known excessively. The purposes of this research are: (1) to know the biomass and carbon content at above ground level of G. sepiumin Wanagama I Teaching Forest. (2) To buildan estimation model of biomass and carbon of G. sepium. (3) to know the potential of G. sepium in Wanagama I Teaching Forest in terms of biomass and carbon storage, and (4) to know the potential of CO2 absorption of G. sepium at above ground level. Fifteen G. sepiumwith various diametersfrom 1-15 cm were cut as samples to build model for estimating biomass, carbon, and CO2 absorption at above ground level. These samples were taken at compartment 5 with the plantation age of 34 years old. The biomass content was determined by drying up the samples of stem and branch at the temperature of 103±2°C and also leaf samples at the temperature of 60±2°C until reaching the constant dry weight. The carbon content was obtained by spectrophotometric analysis. The CO2 absorption was obtained by the atomic mass ratio. The average of biomass content in G. sepium samples at above ground level are as follow: stem organ 23,24 kg, branch organ 12,65 kg, andleaf organ 0,29 kg, while the average of carbon content are as follow: Stem organ 11.06 kg, branch organ5,74kg, and leaf organ 0,12 kg. The estimation model of biomass and carbon of G. sepium at above ground level 6are as follow: biomass Bt = 0,084(D)2-638 (R2 = 0,924), carbon Ct = 0,036(D)2- 72 (R2 0,924). The potential = biomass and carbon of G. sepium at above ground level in Wanagama I Teaching Forest are as follow: biomass Cio.95 = 82,513 ± 3,075 ton/ha, carbon Cio,95 = 38.430 ± 1.574 ton/ha. The potential of CO2 absorption of G. sepium at above

Kata Kunci : Biomassa, Karbon, CO2, gamal, atasan, Hutan Pendidikan Wanagama I