Judul: Penggunaan Kompos Sampah Pasar dan Arang Sekam terhadap Pertumbuhan Bibit Cabutan Duabanga moluccana Blume
Abstrak: Duabanga moluccana merupakan jenis pionir cepat tumbuh dan memiliki prospek untuk dikembangkan dalam hutan tanaman. Namun terdapat permasalahan dalam perbanyakannya dengan benih, seperti kecambah mudah terserang penyakit lodoh dan pertumbuhan kecambah yang sangat lama. Pengadaan bibit masih banyak menggunakan topsoil sebagai media tumbuh yang dikhawatirkan merusak lingkungan karena jumlahnya terbatas, untuk itu perlu dicari solusi dengan menggunakan subsoil yang diperkaya dengan nutrisi dari bahan organik. Penelitian ini bertujuan mengetahui pengaruh penggunaan kompos sampah pasar dan arang sekam terhadap kualitas bibit cabutan D. moluccana. Bibit D. moluccana ditanam dalam empat perlakuan media tumbuh, yaitu subsoil (P0), subsoil : kompos (4:1, v/v) (P1), subsoil : kompos : arang sekam (3:1:1, v/v/v) (P2), subsoil : kompos : arang sekam (2:1:2, v/v/v) (P3). Hasil penelitian selama tiga bulan menunjukkan bahwa media dengan penambahan kompos dan arang sekam mampu meningkatkan kualitas bibit D. moluccana asal cabutan alam dengan baik. Media P2 menghasilkan bibit dengan pertumbuhan terbaik, yaitu tinggi (26.60 cm), diameter (4.60 mm), berat kering total (18.80 g), dan memiliki nilai indeks mutu bibit terbaik (30 poin)., Duabanga moluccana is a fast-growing pioneer species and has the prospect of being developed in plantation forests. However, there are some problems in propagation by seeds, such as susceptible to dumping off and the germinates grow slowly. Seedling productions are still using topsoil as a growing media which is feared to damage the environment due to its limited number. Therefore, it is necessary to use the subsoils enriched with nutrients from organic materials. This study aims to determine the effect of market waste compost and rice husk charcoal on the quality of D. moluccana wildings. D. moluccana seedlings were planted in four growing media treatments, namely subsoil (P0), subsoil : compost (4:1, v/v) (P1), subsoil : compost : rice husk charcoal (3:1:1, v/v/v) (P2), subsoil : compost : rice husk charcoal (2:1:2, v/v/v) (P3). The results of the three-month study showed that the media with the addition of compost and husk charcoal was able to improve the quality of D. moluccana seedlings. P2 media produced the best seedling growth on height (26.60 cm), diameter (4.60 mm), total dry weight (18.80 grams), and had the best seedling quality index value (30 points).
Keyword: growing media, organic matter, seedlings, subsoil

Judul: Pengaruh pemberian ZPT (Rootone-F) terhadap pertumbuhan stek Duabanga moluccana, Blume.
Abstrak: INTRODUCTION Insufficient supply of raw materials to support wood based industries in Indonesia cause of the changes on orientation for wood supply from natural forest to plantation forest in developing fast growing tree species. Duabanga mollucana Blume, is an Indonesian native fast growing tree species that have good characteristic as raw materials for wood based industries. Vegetative propagation can be done to this species besides their ability to be propagated from seed. Shoot and stem cuttings are alternative ways to obtain qualified seedlings in appropriate amounts and timely manner. Plant growth regulator treatment was expected to increase cutting's survival rate and rooting percentage. Objective of this research was to determine the effect of plant growth regulator on the growth of shoot and stem cutting of Duabanga moluccana. This research would be useful to provide information for the production for high quality seedlings. MATERIAL AND METHOD This research was carried out on green house with KOFFCO system (Komatsu-Forda Fog Cooling System) at Balai Penelitian dan Pengembangan Hutan dan Konservasi Alam, Gunung Batu, Bogor, West Java. from August to october 2010. Materials used in this research were shoot and stem of Duabanga seedlings from selected mother trees (M07) from SEAMEO BIOTROP, Rootone-F, Dithane M-45, rice husk, cocopeat, and zeolite. The experimental design in this research was completely randomized design with 2 factors and 3 replicates. The first factor was source of cutting material (shoot and stem) and the second factor was concentration of plant growth regulator (0 ppm, 500 ppm, 1000 ppm, and 1500 ppm). Growth parameters observed were (1) survival rate, (2) rooting percentage, (3) number of roots, (4) root length, (5) root fresh weight and dry weight (6) shoot fresh weight and dry weight (7) shoot-root ratio. Data was processed with analysis of variance then followed by fisher's LSD test. RESULT AND CONCLUSION Analysis of variance was conducted to explore the impact of all factors on growth parameters, shoot cutting was found to be the most significantly different related to each growth parameters observed; those were (1) survival rate, (2) rooting percentage, (3) number of roots, (4) root length, (5) root fresh weight and dry weight (6) shoot fresh weight and dry weight (7) shoot-root ratio , beside that, stem cuttings was not significantly different related to those growth parameters observed. Rooting percentage on shoot cuttings was 82% and stem cuttings was 0%. Plant growth regulator treatments were not significantly affected cuttings, because control (0 ppm) on shoot cuttings showed high rooting percentage value (77%), followed by 500 ppm (80%), 1500 ppm (83%), and 1000 ppm (87%). Interaction between source of materials and concentration of plant growth regulators was also not significantly related on each growth parameters observed because all of stem cutting could not survive during root primordial initiation, shoot cuttings was also not significantly different related to those growth parameters observed, because control (0 ppm) on shoot cuttings produced significant survival rate (77 %).
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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