Judul: Pengaruh Media semai Terhadap Pertumbuhan Pelita (Eucalyptus pellita F.Muell)
Abstrak: INTRODUCTION. Forest is one of the natural resources which give a lot of benefit for human welfare. Development of plantation forest is expected to serve as substitute for natural forest in supplying wood. Eucalyptus pellita is one of the fast growing-species which has a potential to be developed in plantation forest. Plantation forest always involves the activity of nursery. The use of top soil as growing media in nursery causes soil degradation in the area where the top soil is collected. The objective of this research was learning the effect of various nursery media (as substitutes for soil) on the growth of Eucalyptus pellita seedling. MATERIALS AND METHOD. Materials used in this research were Eucalyptus pellita seed, top soil, sheep manure, compost, rice husk, polybag, cocopeat, peat moss, vermiculite, sawdust, attachment label, and germination box. Experimental design in this research was Randomized Complete Block Design. There were 20 kinds of nursery media (treatments) in this study. Each treatment had 4 replications (blocks). Each treatment in each block comprised 5 polybags. Every polybag was filled with one plant of Eucalyptus pellita. Total number of polybag used was 400 polybags. The variables observed were seedling height (cm), number of leaves (which were measured once a week) and seedling diameter (cm) in the end of experiment period. RESULTS AND DISCUSSION. Application of top soil and sheep manure with volume ratio of 2:1 (M5) produced the highest height growth. Media (cocopeat, peat moss, vermiculite =2:2:1) and sheep manure with volume ratio of 2:1 (M20) showed highest diameter growth. Media of cocopeat and compost with volume ratio of 2:1 (M8) showed the greatest increase in number of leaves. Media of (cocopeat, peat moss, vermiculite =2:2:1) and sheep manure with volume ratio of 1:1 (M19) produced the smallest height / diameter ratio.
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Judul: Manajemen Tempat Tumbuh Tanaman Eucalyptus pellita di PT Perawang Sukses Perkasa Industri, Riau
Abstrak: Eucalyptus sp. is one of the species which be developed in the management of wood fiber plantation. Wood fiber for pulp and paper is important, so need to known the management of site to obtain the optimal growth of Eucalyptus pellita at PT Perawang Sukses Perkasa Industri (PSPI). This research intended to observe fertilization management and maintenance management at PT PSPI. This research used Forest Health Monitoring (FHM) method to take data of plant growth. The cluster had 4 plot Iike circle. The sample was E. pellita 1-4 years. Fertilization management at PT PSPI were basic fertilizer (CIRP/Cristmast Island Rock Phosphate and NPK) and supplementary fertilizer (NPK-1, NPK2, NPK-3). Maintenance Management at PT PSPI were ring weeding, sport spray of herbicide and slash. Maintenancing and fertilizing were given to the plot according to the environmental conditions and the age factor. The best growth increment was in plot P2. P2 had 4.14 diameter increment and 5.72 height increment.
Keyword: fertilization management, maintenance management, site management, industrial forest, Forest Health Monitoring, Eucalyptus pellita

Judul: Invers dari Matriks Tridiagonal Jacobi
Abstrak: Suatu matriks berukuran n×n dinamakan matriks tridiagonal jika untuk . Karya ilmiah ini memberikan algoritma yang mudah untuk menemukan invers ( dari matriks tridiagonal Jacobi yang simetrik dan nonsimetrik. Setiap elemen pada matriks tridiagonal ini adalah bilangan real. Terdapat 3 lema dan 2 teorema untuk menentukan . Lema pertama menunjukkan persamaan utama dalam membuktikan lema-lema dan teorema-teorema selanjutnya. Invers dari matriks yang simetrik dibuktikan oleh lema kedua yang menunjukkan elemen-elemen baris ke- dari . Selanjutnya, lema kedua dilengkapi dengan teorema pertama yang menunjukkan elemen-elemen dengan . Invers dari matriks yang nonsimetrik dibuktikan oleh lema ketiga yang menunjukkan elemen-elemen dengan dan elemen-elemen dengan dibuktikankan oleh teorema kedua.
Keyword: symmetric, nonsymmetric, matrix