Judul: Pengaruh Pupuk Mikro-Biostimulant Cair dan Bahan Organik terhadap Pertumbuhan dan Serapan N, P dan K Tanaman Caisim (Brassica juncea) pada Latosol (Oxic Dystrudept), Darmaga
Abstrak: Latosol fertilty is generally low because of its organic content and lack of nutrient availability. One way to overcome its fertility was to used some fertilizer, both organic and inorganic fertilizers. Fertilizer can be applied to the soil and plants. Fertilizers by plants typically use a liquid fertilizer that is expected can overcome the deficiencies of nutrients and effectiveness of absorption. Sufficient nutrients and balance of plant are necessary. Plants can growth well when they have good support from condition and nature of soil so plants can used nutrients to its full potential. Nutrients needed by plants consist of macro elements (C, H, O, N, P, K, Ca, Mg, and S) and micro elements (Fe, Mn, Mo, B, Cu, Zn, and Cl). If all of the elements were not met, plants would growth abnormal. Micro nutrients needed in smaller amounts than fertilizer macro, but its presence is very important, for example in plant metabolic reactions, especially associated with the activity of the enzyme. Maximum growth and production can be ensured by maintain the amount of macro and micro nutrient status. One way to overcome micro-nutrient deficiencies are generally carried out through the leaves. The purpose of this research was to study the effect of Fertilizer Micro-Liquid Biostimulant and organic matter on growth and N, P and K uptake by Chinese Mustard (Brassica juncea) var. Tosakan in Latosol, Darmaga. The research arranged according to Completely Randomized trial using factorial design of two-factor repeated 5 times. The first factor was the Micro-Biostimulant Liquid Fertilizer (MBC) consisting of 4 levels, ie, MBC-0%, MBC-50%, MBC-100% and MBC-150%. The second factor was an organic matter consist of three doses, ie, without organic matter, 2.5 tons/ha of organic matter and 5.0 tons / ha of organic matter. The results showed that MBC treatment equivalent to 100% recommended doses provide the highest results for fresh weight and plant uptake of N, P and K. Aplication of MBC 100% significantly increased the fresh weight by 21% and nutrient uptake of N 27%, P 29% and K 20% compared with MBC 0%. The application of organic matter (cow manure) 5 ton/ha gave the highest results of the fresh weight and nutrient uptake of N, P and K. The treatment was significantly increased the fresh weight by 24% and nutrient uptake of N 23%, P 24% and K 25% compared with without organic matter. There was no interaction between MBC treatment and application of organic matter for all parameters.
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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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