Judul: Pengaruh Pemupukan Fosfor terhadap Pertumbuhan dan Produksi Beberapa Varietas Kedelai Hitam (Glycine Soja) pad a Budidaya Jenuh Air di Lahan Pasang Surut
Abstrak: Saturated soil culture is a cultivation that gives continuous irrigation and maintains water depth constantly and makes soil layer in saturated condition. Technology of saturated soil culture has been shown to increase soybean production on tidal swamps. The objective of this experiment to study the effect of phosphorus fertilization on the growth and production variety of soybean under saturated soil culture on tidal swamps. The experiment was conducted at Banyu Urip, Tanjung Lago, Banyuasin, South Sumatera, Indonesia from May to September 2013. The experiment used a split plot design with three replications. The main plot of the experiment is black soybean variety consisted of : Ceneng, Cikuray, Lokal Malang and Tanggamus as control . Sub plot is the dosage of phosphorus fertilization consisted of : 0, 36, 72 and 108 kg P2O5 ha-1. The results showed that the variety and phosphorus fertilization affected soybean productivity. The highest productivity was obtained on Cikuray variety with phosphorus fertilization 108 kg P2O5 ha-1 as much as 4.03 ton ha-1.
Keyword: Tidal Swamp, Saturated Soil Culture, Phosphorus Fertilization, Black Soybean Variety

Judul: Pengaruh Pemupukan Kalium terhadap Pertumbuhan dan Produksi Beberapa Varietas Kedelai Hitam (Glycine soja) pada Budidaya Jenuh Air di Lahan Pasang Surut
Abstrak: Saturated soil culture can prevent oxidation of pyrite from negative influences and it can to improve the productivity of soybean. The objective of this experiment was to study the effect of potassium fertilization on the growth and production of Ceneng, Cikuray, Lokal Malang, and Tanggamus under saturated soil culture on tidal swamp. The experiment was conducted at Banyu Urip, Tanjung Lago, Banyuasin, West Sumatera, from May until September 2013. The experiment used split plot design with 3 replications. The main plot was is variety consisted of Ceneng, Cikuray, Lokal Malang, and Tanggamus. The sub plot was is potassium fertilization consisted of 0, 30, 60 and 90 kg K2O ha-1. The experiment results show that kalium fertilization increased yield of black soybean. Productivity was affected by single factors that is variety and potassium fertilization. The interaction between variety and potassium fertilization did not effect to the all variables. The highest productivity of black soybean was obtained from Ceneng variety, 3.58 ton ha-1. The potasium fertilization 90 kg ha-1 gave the highest productivity as such as 3.72 ton ha
Keyword: saturated soil culture, potassium, Lokal Malang, Cikuray, Ceneng

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