Judul: Pengaruh Penggunaan berbagai Pupuk Daun terhadap Pertumbuhan Caisim (Brassica juncea L)
Abstrak: Indonesia merupakan negara agraris yang berarti pertanian memegang peranan penting dalam mendukung sektor ekonomi, sosial, dan budaya bangsa. Kesuburan tanah merupakan salah satu kunci penting dalam mencapai keberhasilan produktivitas pertanian. Pemakaian pupuk secara intensif merupakan kegiatan yang umumnya dilakukan petani untuk meningkatkan kesuburan tanah. Oleh karena itu berbagai alternatif teknologi maju dikembangkan dalam bidang pertanian, salah satunya adalah penggunaan pupuk daun. Tujuan dari penelitian ini adalah melihat pengaruh berbagai pupuk daun serta memilih pupuk daun terbaik yang efektif dalam meningkatkan produktivitas tanaman. Dalam penelitian digunakan tanaman caisim (Brassica juncea L) sebagai tanaman uji. Penanaman dilaksanakan di rumah plastik di halaman belakang Laboratorium Pengembangan Sumberdaya Fisik Lahan. Analisis kadar hara urin kambing, pembuatan pupuk MTA serta analisis tanaman dilakukan di Laboratorium Kimia dan Kesuburan Tanah, dan Laboratorium Pengembangan Sumberdaya Fisik Lahan, Departemen Ilmu Tanah, Fakultas Pertanian, Institut Pertanian Bogor. Penelitian ini menggunakan RAL dengan enam perlakuan dan tiga kali ulangan meliputi kontrol (K), pupuk anorganik berupa pupuk Gandasil D (PG), pupuk MTA (PA), pupuk GDP (PB), pupuk GDL (PC), dan pupuk organik berupa pupuk urin kambing kacang (PU). Pemupukan dapat mempengaruhi pertumbuhan caisim. Hal tersebut dapat dilihat dari tinggi, jumlah daun, bobot basah, dan bobot kering yang dihasilkan dari kelima perlakuan lebih baik dibandingkan kontrol. Hasil penelitian menunjukkan bahwa kadar hara N, K, dan Ca pada perlakuan PA, PU, dan PG tidak berbeda nyata sedangkan kadar hara P dan Mg berbeda nyata. Hal ini disebabkan karena perlakuan PU mengandung unsur N yang relatif sama dengan perlakuan PA. Secara keseluruhan, produksi tertinggi diperoleh pada perlakuan PA dan disusul oleh perlakuan PB dan PU. Hasil penelitian juga menunjukkan bahwa serapan hara N dan P pada perlakuan PA, PU, PG berbeda nyata sedangkan serapan hara K, Ca, dan Mg tidak berbeda nyata. Efisiensi pupuk menunjukkan bahwa perlakuan PA dan PU tidak berbeda nyata pada unsur N dan K, tetapi berbeda nyata pada unsur P. Secara keseluruhan, efisiensi pupuk N dan P tertinggi diperoleh pada perlakuan PA, efisiensi pupuk K dan Ca pada perlakuan PB serta efisiensi pupuk Mg pada perlakuan PG.
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Judul: Pengaruh pupuk organik cair pada produksi dan serapan hara tanaman Caisim (Brassica juncea) varietas Tosakan pada Latosol Darmaga
Abstrak: Indonesia is situated in tropical region with high rainfall and temperature. These high rainfall and temperature affect the soil fertility through intensive weathering and leaching process. Leaching process could lead the decrease of basic cations and other important elements for plant. Further it makes soils in Indonesia acid and infertile. One of ways to improve the soil fertility is the application of fertilizer. The fertilizers could be applied through leaf and soil. Leaf fertilizer is applied by using foliar feeding method directly to the leaf so the essential nutrient absorbed by itself through the leaf. Leaf fertilizer is in liquid form, enrich by macro and micro nutrients. The objectives of this research were to determine the effect of liquid organic fertilizer to the yield, nutrient content and nutrient uptake of nitrogen (N), phosphorus (P) and potassium (K) of the caisim (Brassica juncea). This research also aims to determine the effectiveness of fertilizer that is measured by Relative Agronomic Effectiveness (RAE). The experiment was conducted in the greenhouse of University Farm in Cikabayan, Bogor. Analysis concerning nutrient content and plant uptake of N, P and K were carried out in Chemical and Soil Fertility Laboratory, Agricultural Faculty, IPB. Greenhouse expriment was set up in Completely Randomize Design (CRD) with seven treatments and four replications The treatments were as follows: control, standard (S), 0,75PO+0,5S, 0,75PO+0,75S, 1,0PO+0,5S, 1,0PO+0,75S, dan 1,25PO+0,5S. Standard was the treatment using Urea, SP-36 and KCl fertilizers with the rates 200kg/ha, 300kg/ha and 100 kg/ha respectively. PO in the treatments label referred to leaf organic fertilizer while S referred to standard. As for liquid organic fertilizer, the recommended rate was 5 L/ha. The result showed the addition liquid organic fertilizer (PO) and standard fertilizer in lower dose (0,5S and 0,75S) effective in improving the yield of caisim. Nutrient uptake (N and K) in these treatments (0,75PO+0,75S and 1,0PO+0.75S) tended to have higher value than the standard. Meanwhile nutrient uptake (P) in combine dose of PO and S have higher value than standard. In RAE value, the combine dose gave a higher tendency than the standard, whereas this combine dose of treatment (1,0PO+0,5S) resulted in higher value than those of others treatments. Based of the results and considering the RAE values, it suggested that treatment of 1,0PO+0,5S was recommended as fertilizer dose that should be applicated.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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