Judul: Serangan Uret Dan Cara Pengendaliannya Pada Tanaman Eucalyptus Hybrid Di Hutan Tanaman Pt. Toba Pulp Lestari Sektor Aek Na Uli Sumatera Utara
Abstrak: PT Toba Pulp Lestari Tbk is one of the companies which undertake the business of Industrial Plantation Forest (HTI) in Sumatra Utara Province. The objective of the undertaking was producing pulp wood for paper raw materials. The developed plant species was Eucalyptus spp which constituted a fast growing species. According to information from PT Toba Pulp Lestari, one kind of pest which often attacks Eucalyptus spp was insect grub. The attack by this grub often occurs in Sector of Aek Na Uli. This grub attacks roots of plants which are 1- 3 months old, and up to now this problem has not been able to be controlled yet. The objectives of this research were determining the kinds of grub which attacked Eucalyptus in the HTI area of Toba Pulp Lestari in Aek Na Uli sector, determining the effect of attack and the extent of loss created by the grub attack, learning the controlling technique practiced by the company, and learning the effectiveness of insecticide for controlling the grub. edit. This research was conducted in 2 months old Eucalyptus hybrid plants in compartment D 095 with area size of 5.8 ha in Aek Nauli sector, the province of North Sumatra, from 1 April through 20 May 2008. Equipments used in this study were 25 m plastic rope, 14 m plastic rope, compass, wooden pegs, digital camera, and insect collection bottles. Materials used in this study were Karbofuran 3-G and formalin 2 %. Research procedure comprised the counting of the number of eucalypt trees existing in the measurement plot, counting the number of eucalypt trees which were attacked by the grub, examining the tree condition which suffered attack from the grub (wilting, drying, dying), and collecting the various kinds of attacking grubs for identification purpose. Research results showed that percentage of grub growth in each plot was 90.67 % on the average. Species of grub which attacked eucalypt trees in compartment D 095 were Leucopholis rorida, Lepiodata stigma, and Euchlora viridis. On the basis of attack percentage in each measurement plot, the grub attack on Eucalyptus hybrid was categorized as nearly uniform in all compartments. Percentage of plants which suffered attack by grub in compartment D 095 reached 18 % or around 240 trees per hectare. The material loss due to attack by grub in compartment D 095 Rp 189.976,8. Control action conducted in the field to overcome the attack by this grub was by replanting of failures. The use of Karbofuran 3 – G with dosage of 10 gram / planting hole was effective enough to control the grub attack. Key words: PT Toba Pulp Lestari, grub, Eucalyptus hybrid, compartment, Karbofuradan 3-G.
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Judul: Inventarisasi dan diskripsi kerusakan hutan tanaman Eucalyptus urophylla Blake karena serangan serangga di Site Sebulu, HTI Pt. Surya Hutani Jaya, Kalimantan Timur
Abstrak: Indonesia adalah negara tropis dan banyak dari wilayah yang ada terdiri dari hutan. Pembangunan industri perkayuan yang semakin pesat menuntut tersedianya bahan baku yang cukup dan berkesinambungan. Hingga saat ini pemenuhan bahan baku industri perkayuan dipenuhi oleh hutan alam, yang pada tahun 2000 nanti hanya memenuhi bahan baku industri perkayuan sekitar 50-60%. Mengingat hal tersebut pemerintah Indonesia pada tahun 1984 mencanangkan penanaman kawasan hutan yang tidak produktif dengan jenis tanaman yang cepat tumbuh yang disebut Hutan Tanaman Industri/HTI/ Timber Estate, salah satu jenisnya adalah jenis E. urophylla. Bentuk penanaman dalam hutan tanaman industri yang monokultur memungkinkan tanaman terserang oleh hama dan penyakit cukup besar, demikian juga pada tanaman HTI dari jenis Eucalyptus. Untuk menunjang keberhasilan pembangunan HTI maka perlu dilakukan penelitian mengenai berbagai jenis serangga serta peranannya terhadap tegakan. Demikian juga dengan berbagai jenis serangga pada tanaman E.urophylla pada berbagai tingkat umur, terutama yang berpotensi sebagai hama tanaman. Penelitian ini dilakukan di HTI PT. Surya Hutani Jaya, Site Sebulu, Kalimantan Timur. Metode yang digunakan dalam penelitian ini yaitu metode Penarikan Acak Berlapis (Stratified Random Sampling), pada area seluas kurang lebih 3000 ha. tanaman E. urophylla di area dibagi menjadi 4 kelas umur yaitu 1,3,5 dan 6 tahun. Pengambilan sampel tanaman pada petak ukur seluas 20 m x 50 m berbentuk empat persegi panjang....
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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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