Judul: Aplikasi Pupuk Phonska Cair terhadap Produksi Kubis
pada Andisol Pasir Sarongge Kabupaten Cianjur Jawa Barat.
Abstrak: Pemupukan yang efektif diperlukan dalam menunjang produksi pertanian. Pertanian skala luas membutuhkan teknik aplikasi pupuk yang cepat dan efisien dalam penggunaan tenaga kerja. Pemupukan lewat penyemprotan ke daun sebagian besar dilakukan pada komoditas hortikultura. Kubis merupakan salah satu komoditas hortikultura yang sangat penting dan ditanam secara luas. Budidaya tanaman kubis cukup menjanjikan. Tujuan penelitian ini yaitu mengevaluasi pupuk Phonska cair pada budidaya tanaman kubis. Penelitian ini menggunakan Rancangan Acak Kelompok (RAK) dengan tujuh perlakuan dan tiga ulangan. Komoditas yang dipakai yaitu tanaman kubis yang ditanam pada lahan percobaan Pasir Sarongge, IPB University. Hasil uji aplikasi pupuk tidak berpengaruh nyata pada parameter pertumbuhan dan produksi tanaman kubis. Analisis tanah sebelum perlakuan untuk tiga blok menunjukkan bahwa pH agak masam, C-organik tinggi sampai sangat tinggi, N-total sedang sampai tinggi, P-tersedia sangat tinggi, basa-basa dapat dipertukarkan (Ca, Mg, dan K) berkisar dari sedang sampai sangat tinggi, sedangkan Na umumnya rendah. Kejenuhan basa (KB) berkisar dari rendah sampai tinggi dan kejenuhan Al adalah sangat rendah, sedangkan analisis tanah setelah perlakuan menunjukkan adanya perubahan baik kenaikan atau penurunan sifat kimia tanah. Hasil analisis tanah setelah perlakuan menunjukkan bahwa pH umumnya agak masam sampai masam, C-organik tanah tinggi sampai sangat tinggi, dan P-tersedia sangat tinggi. Basa-basa dapat dipertukarkan (Ca, Mg, dan K) berkisar dari sedang sampai sangat tinggi sementara Na umumnya rendah. Kejenuhan basa berkisar dari sedang sampai sangat tinggi dan kejenuhan Al adalah sangat rendah. Nilai Relative Agronomic Effectiveness semua perlakuan pemberian pupuk relatif lebih besar dari perlakuan pupuk standar. Nilai R/C rasio dan B/C rasio dari seluruh perlakuan menunjukkan bahwa usaha tani kubis sudah layak atau sudah menguntungkan dari aspek finansial. Berdasarkan hasil penelitian, perlakuan 500 kg/ha Petroganik, 400 kg/ha Phonska 15:10:12, 300 kg/ha ZA, 5 l/ha Phonska Cair 10:8:3 memberikan pengaruh paling baik dari sisi produksi karena memiliki bobot biomasa tertinggi, bobot krop tertinggi, diameter krop terpanjang, dan nilai RAE paling besar., Effective fertilization is needed to support agricultural production. Large scale farming requires fertilizer application techniques that are fast and efficient in the use of labor. Fertilization by spraying leaves is mostly done on horticultural commodities. Cabbage is a very important horticultural commodity and is widely cultivated. Cabbage cultivation is quite promising. The aim of this research was to evaluate liquid Phonska fertilizer in cabbage plants. This research used a Randomized Group Design (RGD) with seven treatments and three replications. The commodity used was cabbage plants planted on the Pasir Sarongge experimental land, IPB University. The results of the fertilizer application test did not have a significant effect on the growth and production parameters of cabbage plants. Soil analysis before treatment of tree blocks showed that the pH were slightly acidic, organic C were high to very high, total N were medium to high, available P were very high, exchangeable bases (Ca, Mg, and K) ranged from medium to very high while Na were generally low. Base saturation ranged from low to high and Al saturation were very low. Meanwhile soil analysis after treatment showed changes in either increasing or decreasing soil chemical properties. The results of soil analysis after treatment showed that the
Keyword: B/C ratio, R/C ratio, soil analysis, Relative Agronomic
Effectiveness

Judul: Phosphorus  fertilization  optimization  for  caisin (brassica rapa l. cv. Caisin)  of Andisols
Abstrak: Penelitian ini dilakukan untuk memperoleh dosis optimum pemupukan fosfor tanah Andisol. Penelitian dilakukan di Kebun Percobaan Pasir Sarongge Cianjur dari April hingga Mei 2014. Percobaan ini menggunakan rancangan Split Plot design.Bedeng utama (main plot) adalah pengkondisian hara P tanah yang terdiri atas lima taraf, yaitu X (1856.3 kg per ha P 2O5 ), 3/4 X (1392.225 kg per ha P 2O5 ), 1/2 X (928.15 kg per ha P 2O5 ), 1/4 X (464.076 kg per ha P 2O5 ) dan 0 X (0 kg per ha P 2O5). Anak Bedeng (sub plot) adalah dosis pemupukan P yang terdiri atas lima taraf, yaitu X (1856.3 kg per ha P 2O5 ), 3/4 X (1392.225 kg per ha P 2O5 ), 1/2 X (928.15 kg per ha P 2O5), 1/4 X (464.076 kg per ha P 2O5 ) dan 0 X (0 kg per ha P 2O5). Dimana X = 1856.346 kg P2O5 per ha atau 5156 kg SP-36 per ha, yaitu P yang dibutuhkan untuk mencapai kadar P sangat tinggi pada tanah Andisol Pasir Sarongge. Dosis N dan K yang digunakan adalah 200 kg per ha Urea (45% N) dan 100 kg per ha KCL (60% K 2 O). Pengkondisian hara P tanah berpengaruh sangat nyata terhadap pertumbuhan dan hasil tanaman caisin. Perlakuan pemupukan P tidak memberikan pengaruh yang nyata terhadap pertumbuhan dan hasil tanaman caisin pada tingkat kesuburan tanah sedang pengekstrak Bray. Serangan penyakit akar gada dapat menjadi penyebab pemupukan tidak berpengaruh pada tanaman. Persentase jumlah tanaman yang terserang penyakit akar gada adalah 11.90%. Dosis rekomendasi pemupukan P di Kebun Percobaan Pasir Sarongge belum dapat ditentukan, This study was conducted to find out the optimum of phosphorus fertilization on andisol. The study was conducted at the Experimental Farm Pasir Sarongge Cianjur from April to May 2014. This study arranged in split plot design. The main plot is conditioning the soil of P consisting of five rates, namely X (1856.3 kg/ha P2O5), 3/4 X (1392.225 kg/ha P2O5), 1/2 X (928.15 kg/ha P2O5), 1/4 X (464.076 kg/ha P2O5) and 0 X (0 kg/ha P2O5). Subplot is a rate of fertilizer P which consists of five levels, namely X (1856.3 kg/ha P2O5), 3/4 X (1392.225 kg/ha P2O5), 1/2 X (928.15 kg/ha P2O5), 1/4 X (464.076 kg/ha P2O5) and 0 X (0 kg/ha P2O5). Where X = 1856.346 P2O5 kg/ha or SP-36 5156 kg/ha, ie P is needed to achieve very high levels of P in the soil Andisol Pasir Sarongge. Dose of N and K were used was 200 kg ha upper of urea (45% N) and 100 kg ha upper KCl (60% K2O). The results showed that the conditioning of the soil nutrient P is able to enhance the growth and yield of caisin, whereas P fertilization treatment did not give significant effect on the growth and yield of caisin. P fertilization treatment did not give a significant effect on the growth and yield of crops on soil fertility extracting Bray. Mace root disease may be the cause of fertilization had no effect on the plant. The percentage of plants affected mace root
Keyword: pupuk, P tanah, sayuran

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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