Judul: Pendugaan simpanan karbon di areal hutan bekas tebangan PT Ratah Timber Kalimantan Timur
Abstrak: Forests is one of natural resources that can be updated (renewable natural resources) and essential stock for human life. In using of forest resources if not a sustainable manner can lead to increased greenhouse gas (GHG) emissions. These emissions cause global warming and climate change. Indonesia plays a role to reduce GHG emissions (CO2) due to its vast forests that can absorb and store carbon in forest biomass is large enough. This study aims to estimate the carbon storage found in logged-over forest areas in PT Ratah Timber East Kalimantan. Field research was conducted on the logged plots and testing sample tree in the Laboratory of Wood Anatomy and Wood Quality Improvement, Product Forest Ministry, Bogor Agricultural University. The experiment was conducted from April to May 2010. Data were collected from thirty-plot by measuring the diameter base on breast height, total height, and identify the types of trees found in research plots. Furthermore, next treatment is felling tree with the size of sample 5-10 cm to estimate the biomass in forest stands. The results showed that the number of tree species found in research plots covering an area of 3 ha covering 68 species of saplings were 63 species, 49 poles and tree species as many as 48 species. Based on the grouping of species, groups of dipterocarpaceae species of 24.34 ton/ha and non dipterocarpaceae at 128.66 ton/ha, thus it needs enrichment to the dipterocarpaceae species in logged-over forest areas for the preservation of further management. Estimation of carbon savings by using the carbon content of 50% and to estimate biomass with allometric equations that have been made from samples harvested sample trees is 0,0977237 D2,58. Estimation of carbon storage in stands including the saplings amounted to 5,05 ton/ha (3,27%), poles 18,82 ton/ha (10,24%), and trees of 133,57 ton/ha (86,49%). Total storage carbon contained in PT Ratah Timber, East Kalimantan, at 157,44 ton/ha or 122,92 x 10-4 Gt, where the trees had the largest percentage of carbon storage is 84,84%, followed by poles 10,05%, 3,21% saplings, litter 1,87%, and 0,04% lower plants.
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Judul: Pendugaan simpanan karbon yang terikat di areal hutan bekas kebakaran PT. Ratah Timber, Kalimantan Timur
Abstrak: Forest is one of natural resources that can be renewable and essential for human life. Forest fire is one of the disorders that occur in the forest. Forest fires cause reduced carbon stored in forests. This study aims to estimate the carbon bound stored in forestland after forest fires in PT. Ratah Timber, East Kalimantan. In this research, carbon bound storage prediction using destructive methods. Data were collected with a plot size 20 m x 50 m in the area of former forest fire as many as 30 pieces. Data was collected base on type of tree, diameter at breast height (dbh), tree height and wet weight. The samples taken are examples of trees with a diameter of 5-9 cm by 30 samples. Dry weight samples were obtained from measurements in the laboratory. Biomass estimators model used is the model by using variable diameter and total height that is B = 0,113501 D1, 22 T1,12. Carbon storage is obtained from half the value of biomass. The results showed that the bound total carbon stored in forestland after forest fires in PT. Ratah Timber, East Kalimantan used for 19,629 tons/ha and a whole area of 168,817 x 103 ton. Trees can provide carbon savings of 34,20 % of total carbon stored while the poles could contribute carbon savings of 33,66% of total carbon savings. Sapling also contribute enough carbon savings that is equal to 18,10% of the total carbon savings. Litters and under plants are also able to absorb carbon in forests. Litters is able to provide carbon deposits 13,05% of total carbon stored while under plant carbon deposits contribute 0,99% of total carbon savings. Saplings and poles contribute significant of saving carbon on the forest.
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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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