Judul: Pengaruh Pengapuran, P, dan K terhadap Pertumbuhan dan Produksi Kedelai Hitam pada Budi Daya Jenuh Air di Lahan Pasang Surut
Abstrak: This research was conducted to study the effect of lime ameliorant, P and K fertilizer on the growth and productivity of black soybean under saturated soil culture on tidal swamps, in Banyu Urip Village, Tanjung Lago Sub District, Banyuasin District, South Sumatera Province on May-August 2014. This experiment used Block Randomized Design, three factor with three replication. First factor is ameliorant of lime, consisted of 4 levels, i.e: 0, 1 000, 2 000 dan 3 000 kg ha-1 dolomit. Second factor is P fertilizer, consisted of 2 levels, i.e: 36 and 72 kg ha-1 P2O5 . Third factor is K fertilizer, consisted of 2 levels, i.e: 30 and 60 kg ha-1 K2O. This research result showed that the interaction P and K fertilizer influenced on the plant height, leave number, branch number, nodule dry weight, and productivity. The interaction P and lime influenced on the leave number on 8 Week After Planting. The interaction K and lime influenced on the branch number. The highest productivity was obtained on 3000 kg ha-1 dolomit (4.063 ton ha-1 ).
Keyword: Bogor Agricultural University (IPB), marginal land, saturated soil culture, ameliorant and fertilizer

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