Judul: Pengembangan Penggunaan Metode Direct Seeding untuk Rehabilitasi Lahan Pasca Tambang PT Tunas Inti Abadi, Kalimantan Selatan
Abstrak: The method of direct seeding is developed in post mining land in order to give the opportunity to seeds to early adapt with extreem condition in post mining land. This method is implemented in impermanent reclamation land by small mining enterprises caused of its cheap operational cost. The objective of this research is to find out the efficiency of direct seeding method and the suitability of four species; trembesi (Samanea saman), sengon (Falcataria moluccana), sengon buto (Enterolobium cyclocarpum), and randu (Ceiba pentandra) in reclaiming post mining land. The research was conducted implementating three experiments: Experiment I implemented Seeds Physical and Physiological Quality Testing, Experiment II is Forest Species Seeds Adaptation in Post Mining Land, and Experiment III is Effect of Manure Addition in Seed Germination and Growth of Direct Seeding Results. Seed physical quality testing with 1000 grain weight method used the seeds which are classified into small size seeds (sengon and randu) and medium size seeds (trembesi and sengon buto). Based on physiological quality testing, the result of experiment I is 66.67% - 86.67%, Experiment II is 11.2% - 31.6%, and Experiment III is 7.2%-13.2%. Manure addition has significantly influenced the height and diameter growth in Experiment III, but not to the survival rate of plantation. In Experiment II, at the age of twelve weeks, the height of randu plantation was 9.6 cm; trembesi 7.9 cm; and sengon 3.6 cm. The diameter of sengon buto was 4.35 mm; randu 2.12 mm; trembesi 1.91 mm; and sengon 0.98 mm. The result of Experiment III is that average height of sengon buto was 41.5 cm; trembesi 15.4 cm; randu 12.4 cm; and sengon 7.4 cm. The diameter of sengon buto was 5.46 mm; trembesi 2.47 mm; randu 2.42 mm; and sengon 1.12 mm. The survival rate based on the plantation hole in Experiment II was the survival rate of randu and sengon was 66%; trembesi 58%; and sengon bruto 52%. In Experiment III, the higest survival rate was trembesi 72% followed by randu 40%, sengon 38% and sengon buto 28%. From the result of these four species used in the experiment, all of the species are highly adaptive with extreme condition in post mining land and suitable to implement with direct seeding method. It is also identified that size of seed highly influenced the successfulness of direct seeding. Small size seeds are the most suitable one in competition with weed. Direct seeding is more economic with plantation cost of 2 million rupiahs per hectare compared with conventional seeding method with cost of 4.487.500 rupiah per ha.
Keyword: 

Judul: Kajian hasil-hasil penelitian tentang tingkat pertumbuhan berbagai jenis pohon pada lahan pasca tambang
Abstrak: Mining would give direct negative impact on environmental condition, there are opened soil surface that will increase surface run-off; change on forest ecosystem and forest ecology stability. Objective on post mining area rehabilitation is to construct post mining area fit in the land purpose. Collection results of researches in growth of many trees species is important to know the development of technique and detect the success rate with its factors. The objective of this research to evaluate result on researches collected. This research was carried out by collect and analyze the result of growth on many tree species in post mining area on Laboratorium Bioteknologi Hutan dan Lingkungan ; dan Pusat Penelitian Sumberdaya Hayati dan Bioteknologi (PPSHB) library, University library and Department of Forest Resources Conservation and Ecotourism library at Bogor Agricultural University. Many research resulted there were several tree species which used in rehabilitation post mining area were akasia, lamtoro, gamal, sengon, jarak pagar, pulai, gaharu, nyatoh, kapur naga, mindi, melochia, cemara gunung, nyamplung, ubak, rengkat, leban, and waru . Over tailing in post tin mining area akasia, lamtoro, gamal and sengon well grown with Mycofer and compost treatment beside that jarak pagar seedlings well grown in mixed ameliorant and anorganic fertilizer tratment. Over batu bara tailing, sludge acquition increasing growth of mangium and acacia. Topsoil acquition increasing seedlings growth of pulai species. FMA inoculation and soil amandement treatments increasing grown of agarwood species. Soil amandement treatment given positive effect on seedlings of nyatoh and kapur naga species. Over post gold mining area, combination of active compost and FMA helped mindi species to grown up. Over post nickel mining area, melochia species well grown in fertilizer treatments, beside that grass controlling system helped cemara gunung grown well. Over post tin mining area nyamplung, ubak, rengkat, laban and waru grown up with water splash treatment.
Keyword: 

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.
Keyword: