Kesimpulan
1. Model pertumbuhan diameter tegakan Acacia mangium di PT. Sumalindo Hutani Jaya II adalah D=58, 885U0,539N−0,346 dengan nilai R2 sebesar 89,25%, R2adj sebesar 88,87%, RMSE sebesar 1,29, dan S sebesar 12,98%. 2. Model pertumbuhan tinggi tegakan Acacia mangium di PT. Sumalindo
Hutani Jaya II adalah T=4, 271 3, 646 ln+ U2,327, dengan nilai R2 sebesar 91%, R2adj sebesar 90,69%, RMSE sebesar 1,32, dan S sebesar 15,11%. 3. Model pertumbuhan volume per hektar tegakan Acacia mangium di PT.
Sumalindo Hutani Jaya II adalah 1
0, 01 0, 516 0,1
V U N
e e
= − −
+ + , dengan
nilai R2 sebesar 89,19%, R2adj sebesar 88,81%, RMSE sebesar 9,36, dan S sebesar 42%.
4. Kerapatan tegakan memiliki pengaruh yang lebih besar terhadap pertumbuhan diameter dibandingkan terhadap pertumbuhan tinggi.
5. Daur optimum untuk tegakan Acacia mangium di PT. Sumalindo Hutani Jaya II adalah pada saat umur 5,25 tahun.
Saran
1. Mengingat pertumbuhan dipengaruhi oleh berbagai macam faktor, oleh karena itu diperlukan penelitian lebih lanjut mengenai pertumbuhan dengan penambahan peubah bebas seperti kualitas tempat tumbuh.
2. Untuk mendapatkan hasil yang lebih baik, diperlukan penambahan variasi data dari berbagai umur sehingga dapat dihasilkan persamaan yang lebih baik dan lebih mewakili.
3. Diperlukan data tambahan berupa pohon peninggi dengan tujuan agar dapat menyusun kurva pertumbuhan berdasarkan kualitas tempat tumbuh yang ada di PT. Sumalindo Lestari Jaya Tbk.
Amaro, Ana, D. Reed, M. Tome, and I. Themido. 1998. Modeling Dominant Height Growth : Eucalyptus Plantations in Portugal. Society of American Foresters. Forest Science 44(1): 37-46.
Badan Penelitian dan Pengembangan Kehutanan. 1994. Pedoman Teknis Penanaman Jenis-Jenis Kayu Komersil. Departemen Kehutanan Badan Penelitian dan Pengembangan Kehutanan. Jakarta.
Badan Penelitian dan Pengembangan Kehutanan. 1998. Pedoman Pembangunan Hutan Tanaman Industri . Departemen Kehutanan Badan Penelitian dan Pengembangan Kehutanan. Jakarta.
Bruce, D and FX Schumacher. 1950. Forest Mensuration. Mc Graw-Hill Book Company Inc. New York.
Budiyanto. Eko. 2002. Model Pertumbuhan Rata-Rata Diameter dan Rata-Rata Tinggi Pohon Untuk Tegakan Agathis loranthifolia Salisb. Skripsi. Jurusan Manajemen Hutan Fakultas Kehutanan Institut Pertanian Bogor. Tidak Diterbitkan.
Davis, LS and KN Johnson. 1987. Forest Management 3rd Edition. Mc. Graw-Hill Book Company Inc. New York.
Harbagung. 2004. Model Hasil Tegakan Hutan Tanaman Acacia mangium Willd. Di daerah Semaras Pulau Laut Kalimantan Selatan. Bul. Pen. Hutan 644: 11-30.
________. 2004. Model Hasil Tegakan Hutan Tanaman Acacia mangium Willd. Di Kecamatan Tungkal Ulu, Kabupaten Tanjung Jabung Barat Jambi Sumatra. Bul.Pen. Hutan 645: 1-23.
Husch, Charles Miller, and Thomas beers. 1982. Growth of The Tree. John Willey and Sons Inc. Krieger Publishing Company: Florida.
Kramer, PJ and TT. Kozlowski. 1960. Physiology of Trees. Mc Graw-Hill Book Company. New York.
Loetsch F, F Zohrer, and KE Haller. 1973. Forest Inventory Vol II. Translataed to English by KF Panzer. BLV Ver Lagsgesell Schaft. Muenchen. Malik, Jamaludin, Adi santoso, dan Osly Rachman. 2000. Himpunan Sari Hasil
Penelitian Mangium dan Tusam. Badan Penelitian dan Pengembangan Kehutanan dan Perkebunan. Bogor.
Nurhasybi. 2000. Atlas Benih Tanaman Hutan Indonesia. Balai Teknologi Perbenihan Vol 2 No.3. Bogor.
Palokangas. 1996. Acacia mangium in Pulp and Paper Production Reforestation : Meeting The Future Industrial Wood Demand. Proceeding of A Workshop Held in Jakarta. Enso Group Nordic Forest Development.
Pandit, IKN. 1995. Anatomi Pertumbuhan dan Kualitas Kayu. Disertasi Fakultas Pasca Sarjana IPB. Bogor. Tidak Diterbitkan.
Prihanto, Budi dan Muhdin. 2005. Metode Statistika Diktat Kuliah. Departemen Manajemen Hutan Fakultas Kehutanan Institut Pertanian Bogor. Bogor.
Prodan, M. 1968. Forest Biometrics. Pergamon Press, Oxford. London. Spurr, SH. 1952. Forest Inventory. The Ronald Press Company. New York. Suhendang, Endang. 1990. Hubungan Antara Dimensi Tegakan Hutan Tanaman
Dengan Faktor Tempat Tumbuh dan Tindakan Silvikultur Pada Hutan Tanaman Pinus Merkusii JungH Et De Vriese di Pulau Jawa. Disertasi Fakultas Pasca Sarjana IPB. Tidak Diterbitkan.
Sumalindo Hutani Jaya II. 2004. Daftar Compartemen Tanaman. HPHTI Sumalindo Hutani Jaya II Site Sei Mao/Bhirawa.
________________________. 2005. Rencana Karya Tahunan 2005. HPHTI Sumalindo Hutani Jaya II Site Sei Mao/Bhirawa.
Vanclay, JK. 1994. Modelling Forest Growth and Yield. CAB International. United Kingdom.
Widodo, P. 1989. Model Pertumbuhan Hasil Tegakan Hutan Tanaman Seumur
Pinus merkusii Jungh et de vriese. Disertasi. Fakultas Pasca
Sarjana IPB. Tidak Diterbitkan.
Wiroatmodjo. 1984. Model Perhitungan Pertumbuhan dan Hasil Kayu Bulat Hutan Tanaman Pinus Merkusii di Jawa. Disertasi Fakultas Pasca Sarjana IPB. Tidak Diterbitkan.
Lampiran 1.
Analisis Ragam Model Pertumbuhan dari software Statistica
Model pertumbuhan Diameter Model is: D=2.444+3.056U2
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5985.162 3.00000 1995.054 905.6697 0.00
Residual 125.562 57.00000 2.203
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 5985.162 3.00000 1995.054 134.0514 0.00
Model is: D=14.812-9.659(1/U)
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5913.707 2.00000 2956.854 870.4694 0.00
Residual 197.017 58.00000 3.397
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 5913.707 2.00000 2956.854 198.6765 0.00
Model is: D=U/(0.159+0.039U)
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5977.022 2.00000 2988.511 1296.411 0.00
Residual 133.703 58.00000 2.305
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 5977.022 2.00000 2988.511 200.804 0.00
Model is: D=U2 /(-0.088+0.252U+0.022U2) Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5985.702 3.00000 1995.234 909.6647 0.00
Residual 125.022 57.00000 2.193
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Model is: D=a+b*(ln(U))^c 5.399+4.367(lnU)1.572
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5986.836 3.00000 1995.612 918.1676 0.00
Residual 123.888 57.00000 2.173
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 5986.836 3.00000 1995.612 134.0889 0.00
Model is: D=a*(1-Euler^((-b)*U))^1/(1-c) 0.759(1-e(-0.332U))1/1-0.956
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5972.984 3.00000 1990.995 823.9154 0.00
Residual 137.741 57.00000 2.417
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 5972.984 3.00000 1990.995 133.7786 0.00
Model is: D= 58.885U0.539N-0.346
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 6016.300 3.00000 2005.433 1210.601 0.00
Residual 94.424 57.00000 1.657
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 6016.300 3.00000 2005.433 134.749 0.00
Model is: D=7.184-0.004N+2.3U-0.05U2
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 6014.151 4.00000 1503.538 871.8553 0.00
Residual 96.573 56.00000 1.725
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 6014.151 4.00000 1503.538 101.0255 0.00
Model is: D=17.521-0.004N-8.083(1/U) Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5944.449 3.00000 1981.483 679.2639 0.00
Residual 166.275 57.00000 2.917
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Model is: D=1/0.071+0.358e +0.1e
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5964.454 3.00000 1988.151 774.7596 0.00
Residual 146.271 57.00000 2.566
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 5964.454 3.00000 1988.151 133.5876 0.00
Model is: D=a+(b*U^(-1))+(c*N^(-1)) 8.628-7.293U-1+4103.482N-1
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5955.513 3.00000 1985.171 729.0349 0.00
Residual 155.212 57.00000 2.723
Total 6110.724 60.00000
Corrected Total 878.083 59.00000
Regression vs.Corrected Total 5955.513 3.00000 1985.171 133.3873 0.00
Model is: Ln D= ln7.332-0.0003N+0.553lnU Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 285.3157 3.00000 95.10523 3304.914 0.00
Residual 1.6403 57.00000 0.02878
Total 286.9560 60.00000
Corrected Total 11.4883 59.00000
Regression vs.Corrected Total 285.3157 3.00000 95.10523 488.427 0.00
Model Pertumbuhan Tinggi
Model is: T=a+b*U+c*U^2 2.687+1.301U+0.247U2
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5221.643 3.00000 1740.548 955.7089 0.00
Residual 103.809 57.00000 1.821
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5221.643 3.00000 1740.548 92.9529 0.00
Model is: T=14.295-10.426(1/U)
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5014.174 2.00000 2507.087 467.1430 0.00
Residual 311.277 58.00000 5.367
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Model is: T= U/0.28+0.012U
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5193.771 2.00000 2596.885 1143.819 0.00
Residual 131.681 58.00000 2.270
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5193.771 2.00000 2596.885 138.685 0.00
Model is: T= U2/-0.228+0.484U-0.023U2
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5223.028 3.00000 1741.009 968.8905 0.00
Residual 102.424 57.00000 1.797
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5223.028 3.00000 1741.009 92.9775 0.00
Model is: T= 4.271+3.646lnU2.327
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5226.048 3.00000 1742.016 998.9053 0.00
Residual 99.404 57.00000 1.744
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5226.048 3.00000 1742.016 93.0313 0.00
Model is: T=a*(1-Euler^((-b)*U))^1/(1-c) 1.301(1-e-0.072U)1/1-0.973
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5193.367 3.00000 1731.122 747.0471 0.00
Residual 132.085 57.00000 2.317
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5193.367 3.00000 1731.122 92.4495 0.00
Model is: T=a*(u^b)*(N^c) 17.577U0.799N-0.223
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5215.701 3.00000 1738.567 902.9404 0.00
Residual 109.751 57.00000 1.925
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Model is: T=a+b*N+c*U+d*U^2 6.122-0.003N+0.753U+0.302U2 Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5236.871 4.00000 1309.218 827.6783 0.00
Residual 88.581 56.00000 1.582
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5236.871 4.00000 1309.218 69.9180 0.00
Model is: T=16.475-0.003N-9.158(1/U) Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5034.075 3.00000 1678.025 328.2603 0.00
Residual 291.377 57.00000 5.112
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5034.075 3.00000 1678.025 89.6139 0.00
Model is: T=1/(a+(b*Euler^(-U))+(c*Euler^(-N))) 1/0.66+0.693e-U+0.1e-N
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5159.939 3.00000 1719.980 592.3321 0.00
Residual 165.513 57.00000 2.904
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5159.939 3.00000 1719.980 91.8545 0.00
Model is: T=a+(b*U^(-1))+(c*N^(-1)) 9.437-8.567U-1+3223.884N-1 Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 5039.979 3.00000 1679.993 335.4414 0.00
Residual 285.473 57.00000 5.008
Total 5325.452 60.00000
Corrected Total 1104.778 59.00000
Regression vs.Corrected Total 5039.979 3.00000 1679.993 89.7190 0.00
Model is: LnT= ln5.172-0.0002N+0.718LnU Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 251.7834 3.00000 83.92780 1823.544 0.00
Residual 2.6234 57.00000 0.04602
Total 254.4068 60.00000
Corrected Total 17.6519 59.00000
Model Pertumbuhan Volume per Hektar
Model is: V=a+b*U+c*U^2 4.071-2.048U+3.347U2
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 93101.58 3.00000 31033.86 329.5882 0.000000
Residual 5367.09 57.00000 94.16
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Regression vs.Corrected Total 93101.58 3.00000 31033.86 39.6716 0.000000
Model is: V=64.637-61.955(1/U)
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 80336.54 2.00000 40168.27 128.4879 0.000000
Residual 18132.13 58.00000 312.62
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Regression vs.Corrected Total 80336.54 2.00000 40168.27 51.3484 0.000000
Model is: V=U/0.16-0.019U
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 92585.09 2.00000 46292.55 456.3491 0.000000
Residual 5883.58 58.00000 101.44
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Regression vs.Corrected Total 92585.09 2.00000 46292.55 59.1772 0.000000
Model is: V=U2/1.112-0.415U+0.052U2
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 93391.74 3.00000 31130.58 349.5111 0.000000
Residual 5076.93 57.00000 89.07
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Regression vs.Corrected Total 93391.74 3.00000 31130.58 39.7952 0.000000
Model is: V= 5.373+17.262lnU2.991
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 93424.61 3.00000 31141.54 351.9120 0.000000
Residual 5044.07 57.00000 88.49
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Model is: LnV= ln4.636+1.639lnU Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 539.4609 2.00000 269.7305 1003.473 0.00
Residual 15.5902 58.00000 0.2688
Total 555.0511 60.00000
Corrected Total 83.7581 59.00000
Regression vs.Corrected Total 539.4609 2.00000 269.7305 190.001 0.00
Model is: V= 2.095U1.921N0.078
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 93056.38 3.00000 31018.79 326.6769 0.000000
Residual 5412.29 57.00000 94.95
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Regression vs.Corrected Total 93056.38 3.00000 31018.79 39.6523 0.000000
Model is: V= -1.127+0.004N-1.197U+3.264U2
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 93136.43 4.00000 23284.11 244.5332 0.000000
Residual 5332.24 56.00000 95.22
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Regression vs.Corrected Total 93136.43 4.00000 23284.11 29.7648 0.000000
Model is: V= 64.363+0.0004N-62.116(1/U) Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 80336.85 3.00000 26778.95 84.18352 0.000000
Residual 18131.82 57.00000 318.10
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Regression vs.Corrected Total 80336.85 3.00000 26778.95 34.23238 0.000000
Model is: V=1/(a+(b*Euler^(-U))+(c*Euler^(-N))) 1/0.01+0.516e+0.1e-N
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 93478.50 3.00000 31159.50 355.9181 0.000000
Residual 4990.17 57.00000 87.55
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Model is: V=a+(b*U^(-1))+(c*N^(-1)) 60.76-60.473U-1+2572.55N-1
Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 80352.97 3.00000 26784.32 84.27531 0.000000
Residual 18115.70 57.00000 317.82
Total 98468.67 60.00000
Corrected Total 46153.91 59.00000
Regression vs.Corrected Total 80352.97 3.00000 26784.32 34.23924 0.000000
Model is: LnV=ln3.191+0.0004N+1.713lnU Level of confidence: 95.0% ( alpha=0.050)
Sum of squares DF Mean squares F-value p-value Regression 539.7026 3.00000 179.9009 668.1005 0.00
Residual 15.3485 57.00000 0.2693
Total 555.0511 60.00000
Corrected Total 83.7581 59.00000
Lampiran 2.
Perkiraan Pertumbuhan Tegakan Mangium (A. mangium) di HPHTI Sumalindo Hutani Jaya II Diameter
Umur (th) Kerapatan tegakan (N/Ha) Perkiraan pertumbuhan (cm)
1 1100 5.23 2 1045 7.74 3 993 9.80 4 943 11.64 5 896 13.37 6 851 15.01 7 809 16.60 8 768 18.16 9 730 19.70 10 693 21.22 Tinggi
Umur (th) Kerapatan tegakan (N/Ha) Perkiraan pertumbuhan (m)
1 1100 4.27 2 1045 5.82 3 993 8.81 4 943 12.07 5 896 15.30 6 851 18.43 7 809 21.43 8 768 24.30 9 730 27.03 10 693 29.66
Untuk pertumbuhan diameter dan tinggi untuk umur 6-10 tahun merupakan estimasi dari model pertumbuhan.
Volume per Hektar
Umur (th) Kerapatan tegakan (N/Ha) Perkiraan pertumbuhan (m3/Ha) Riap Volume
CAI (m3/Ha) MAI (m3/Ha)
1 1100 5.02 - 5.02 2 1020 12.59 21.23 6.29 3 969 28.32 39,09 9.44 4 921 52.43 48.41 13.12 5 876 76.32 37.10 15.26 6 851 91.69 19.48 15.28 7 833 99.03 8.32 14.15 8 792 102.03 3.24 12.75 9 715 103.18 1.22 11.46 10 680 103.61 0.45 10.36
