Judul: Studi Pertumbuhan Tanaman Revegetasi Pasca Tambang Batu Bara di PT Arutmin Indonesia Site Batulicin Kalimantan Selatan
Abstrak: Soil characteristics on post coal mining land is generaly have a high acidity, density, and content of phytotoxic compounds wich potentially causing stunt plants. This study examines the characteristics of the soil and crop growth performance at post coal mining land revegetation of PT Arutmin Indonesia Site Batulicin South Borneo and the correlation between its soil character with plant growth performance at this site. The study was conducted by measuring the height and diameter of acacia and sengon from 26 plots, and conducting soil analysis of chemical and physical soil properties from each plot. This study found some stunt plant, soil density is a factor that most often appears in problem level at this site, and is a factor that has a significant correlation with plant growth performance.
Keyword: 

Judul: Pendugaan Kandungan Karbon pada Tegakan Akasia (Acacia mangium) dan Sengon (Paraserianthes falcataria) di Lahan Reklamasi Pasca Tambang Batubara PT Arutmin Batulicin, Kalimantan Selatan
Abstrak: Indonesia has a vast landscape and abundant natural resources, both renewable and non renewable. Mining is an activity that utilizes the natural resources and potentially change the landscape, so that reclamation should be made as an effort to ensure appropriate land use designation. Reclamation of land by planting trees that will be a forest in the former mining area. Acacia (Acacia mangium) and Sengon (Paraserianthes falcataria) are fast growing species that can be planted on landfill. In addition, Acacia and Sengon also has a function as carbon storage. Acacia and Sengon on land reclamation deliver various carbon savings, so a study on the estimation of carbon stocks of Acacia and Sengon on land reclamation after mining of coal with biomass approach is needed. The research was carried out in reclamation forest of Acacia and Sengon post coal mining in Batulicin, South Kalimantan. Material used is reclamation forest of Acacia and Sengon planted in the post coal mining land in Batulicin, South Kalimantan, since 2005 with 3x4 m planty distance. The tools used in this study including scales, plastic rope, 30 m measuring tape, phiband, knives/machetes, plastic bags, newspapers, cameras and stationery. In both stands 5 plots measuring with 20x20 m plant spacing is made. Then in each corners of the plots a smaller used plot of 4x2x2 m is made for under storey and litter analysis and sample taking. Data acquired is processed though biomass approach then converted to carbon storage in ton/ha. To study the factors that affecting the carbon storage LSD analysis and ANOVA is used. Result shown by this study reveal that carbon storage in Acacia study is greater compared with that in Sengon stand. Carbon storage in Acacia stand is 71,864 ton/ha, while carbon storage in Sengon stand is 31,8853 ton/ha. The carbon storage difference in both stand is affected by tree species. Under storey and litter also the effect of biomass difference in each stand. Based on that data can be concluded that carbon storage potential in reclamation site of PT. Arutmin Batulicin with Acacia study is 117,8695 ton/ha, while carbon storage potential in Sengon study is 31,8853 ton/ha. Acacia vegetation resulting highest carbon content among other vegetation and litter vegetation in Acacia produced higher carbon content compared with litter vegetation in Sengon stand, mean while under storey in Sengon forest resulting higher carbon content compared with under storey vegetation in Acacia stand.
Keyword: 

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology