Judul: Pengaruh terak baja terhadap sifat kimia tanah serta pertumbuhan dan produksi tanaman Padi (Oryza Sativa) pada tanah gambut dalam dari Kumpeh, Jambi
Abstrak: Serious efforts to achieve self sufficiency in rice to fullfil consumption of population growth in Indonesia become very important. One of the most important problems was the decrease of fertile land in Java along with significant numbers of land conversion to nonagricultural usage. One of the important effort to overcome this problem was utilizing peatlands outside Java. Utilizing of peatland for rice cultivation faces many problems such as soil acidity and toxicity of organic acid which effect to crop growth. Steel slag is a by-product furnace in the process of steel manufacturing. These materials can be used as liming material for improving chemical properties of peat soil. This research purposed to evaluate effect of steel slag on chemical properties of soils and also rice growth and yield. Research was carried out of pot experiment in greenhouse by using peat soils from Kumpeh, Jambi. Slags were applied in dosage 0, 1, 2, 3, 4, and 5% or 0, 30, 60, 90, 120, and 150 g / pot, combined with NPK fertilizer in dosage 50 and 75% from standard, compared with control and standard. The result shows that steel slag significantly improved chemical properties of soils such as raised soil pH, exchangeable Ca and Mg, and available Mn in soils. Toxic heavy metal in rice and soils were given by NPK fertilizer treatment. Steel slag also significantly increased rice yield and growth, reduced unfilled spikelets, and also increased nutrient rate of Ca and Mg in crop. In addition, steel slag reduced usage of conventional fertilizer. This was shown by higher value of fertilizer efficiency on steel slag treatment.
Keyword: 

Judul: Pengaruh tebak baja terhadap sifat kimia tanah dan produksi padi sawah pada tanah gambut mukok, Sanggau
Abstrak: Utilization of peat lands as agricultural land especially for wetland rice Eeld faces some prob!ems such as low availability of macro and micro nutrients. Some research results indicated that the availability of silicate in p a t land of Kalimantan and Sumatra is low. The role of silicate oi, wetland rice are increasing the resistafice to lodging, pzst, and disease ss well as improving photosynthesis. This research were conducted ir two steps incubztio~a nd field experiment. In the two experiments, the dosage sf steel slag applied were : 3.0 , 2.5; 5.0; 7.5, and 10 ton /ha or eyuivclen? to 0,3.65,7.03, 11.03 and 14.70 g /kg for kcubation experiment. Result of incubztion experiment indicated that the effect of steel slag on chemical properties of soil were significant. The contents of exchangeable K, Ca and Mg; available Si, Fe, Mr., a~laC u; and soil pH were incresed with incresing the dgsage of steel slag. Results of field experiment indicated that application of steel slag as silicon fertilizer significantly incresed plant height, dry weight of total and filled spikelets; and decreased the percentage of unfillet spikellets. On the other land, the effect of steel slag treatments OI? number of inaximum and productive tilier rice werc not significant. The plant height, dry weight of total and filled spikelets were increased 14-22 %, 61-67 % and 65-96 %; respectively, with application of steel slag; and the percentage of unfilled spikelets was decreased 2.63-4.42 %.
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