Judul: Pengaruh waktu dan titik pengukuran terhadap emisi Karbondioksida dan Metan di lahan gambut kebun Kelapa Sawit PT Perkebunan Nusantara IV, Labuhan Batu, Sumatera Utara
Abstrak: The conversion of forest to estate plantation takes into account by the world because of the high potential of greenhouse gases emission such as CO2 and CH4. This is due to the opening of oil palm plantation widely and the developed of plant forest which is planned by the Indonesian Government in both mineral soil and peatland. The objectives of this research were to (1) measure and examine the flux and emission of green house gases (CO2 and CH4) at the certain ages of the oil palm (TBM, TM 6, TM 12, and TM 18), (2) examine the effect of the distance from drainage and time measurement on greenhouse emission in oil palm plantation at the certain ages (TBM, TM 6, TM 12, and TM 18). This research was conducted at the peatland of oil palm plantation in Panai Jaya and Meranti Paham, PT Perkebunan Nusantara IV, Labuhan Batu, North Sumatera in 2008-2009. The measurement was conducted in the morning and afternoon which was begun by choosing the location based on the distance of 50 m, 100 m, and 150 m from drainage ditch. The gases were sampled under the auspices of the plant, the and of the plant canopy, and the sidelines between plant by using the closed chamber and analyzed by using Micro GC CP 4900 for each plot. Randomized complete block design was applied to identify the effect on emissions. The highest emission of CO2 occured in TM 18 (45.45 tons/ha/year) and then TM 12 (43 tons/ha/year), TBM (41.79 tons/ha/year) and the lowest was in TM 6 (38.52 tons/ha/year). The emission of CH4 decreased with increament of the depth of water table. The highest emission of CH4 was 7.70 tons/ha/year (TM 12) and followed 5.72 tons/ha/year (TBM), 5.59 tons/ha/year (TM 6) and lowest was 5.50 tons/ha/year (TM 18). In general, emission of CO2 increased with further distance from drainage ditch, but there was found that CO2 emission was not affected by the distance of drainage ditch. In line with the effect of time, emission of CO2 in the afternoon is higher than in the morning because of the increasing of temperature, but it was found the opposite which CO2 was not affected by temperature. Analysis of variance showed that CO2 emission was not significantly affected by the distance from drainage ditch and time measurement.
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Judul: Emisi Karbon Dioksida Dari Tanaman Kelapa Sawit Pada Lahan Gambut Di Sumatra
Abstrak: Peatlands are formed by decomposed plants residues, with vegetation that are submerged. The process of peat formation occurs when the rate of deposition exceeds the rate of loss of organic materials. Peatlands in the world only 3% of the entire land, but store 30% of the world terrestrial carbon. Indonesia is estimated to have the largest amount of carbon in tropical peat of 57,4 Gt. Over the past 20 years, peatlands have been converted for agriculture. Oil palm plantations in Indonesia are mostly developed on peat soil. In 1990, the area of oil palm on peat land in Sumatra was 17.985 hectares, and substantially increased up to 1.026.922 hectares in 2010. The development of oil palm on peatland involve drainage that can disturb the capacity of peatlands in storing carbon. This literature study aims to assess the effect of drainage on carbon dioxide emissions of oil palm plantations on peatlands in Sumatera. Drainage of peatlands lead to an increase in carbon dioxide emissions. Separation processes in carbon dioxide emissions shows the contribution of peat decomposition, root respiration, plant biomass and fires for land clearing. Heterotrophic respiration (decomposition of peat) contributes 73% of the total soil respiration and the remaining 27% is from autotrophic respiration (root respiration).
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Judul: Grup dan Homomorfisma Grup pada Rubik Revenge
Abstrak: Rubik cube is a kind of puzzle game. A player must arrange rubik sides, which have been disordered, back to the position where every side has the same colour. This paper does not focus on the settlement solution, but instead on proving the existence of a group homomorphism between rubik movement group and S96 symmetric permutation group in rubik revenge. Firstly, it has been proved that rubik movement set is a group. Then, it also has been proved that the M set, which contains numeric labels of 1 until 96 in cubinos sides, is S96 symmetric permutation group.
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