Judul: Pengaruh abu terbang dan bahan humat terhadap pertumbuhan tanaman sengon (Paraserienthes falcataria) dan sifat-sifat kimia tanah di lahan bekas tambang batubara
Abstrak: Indonesia is the largest coal producer in Southeast Asia. Some problems will appear in coal mining during and after mining especially land degradation. For reclaiming land degradation, some efforts can be done to improve the physical, chemical, and biological properties of soil. Some of the alternatives for soil ameliorant are fly ash and humic substances. Fly ash can be obtained from the coal burning at the electric power plant while humic substances can be extracted from organic materials. Application of fly ash and humic substances in the soil at ex-coal mining are expected to improve the physical, chemical and biological properties of soil. The research aims to find out the effect of fly ash and humic substances on sengon’s growth (Paraserienthes falcataria) and chemical properties of soil in the ex-coal mining land. This research was conducted in a greenhouse, nursery PT. Kaltim Prima Coal, East Kutai, East Kalimantan Province. The research used a completely randomized design factorial of two factors. The first factor were 3 levels of fly ash: 0 tons/ha, 40 tons/ha, and 80 tons/ha, or equivalent to 0 g/polybags, 200 g/polybag, and 400 g/polybag. The second factor were 3 levels of humic substances: 0 l/ha, 15 l/ha, and 30 l/ha, or equivalent to 0 ml/polybags, 0,075 ml/polybags, and 0,15 ml/polybags. Each polybag filled with soil material as much as 10 kg. Each treatment was repeated as many as 5 times. The results showed the interaction between fly ash and humic substances significantly increased the N content, N absorption, plant height, and weight of leaves. The highest result of those parameters was the treatments of F2H2. The analysis also showed that fly ash significantly increased pH, total-N, organic-C, exchangeable-K, exchangeable-Na, exchangeable-Ca, base saturation, K content, Mg content and Mg uptake of leaves, and tended to increase the available-P, P content and P uptake of leaves, and decreased the exchangeable-Al. Humic substances significantly increased the available-P and exchangeable-Ca, and tended to increase pH, C-organic, Cation Exchange Capacity (CEC), Mg uptake of leaves, and decreased the exchangeable-Al.
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Judul: Aklimatisasi pemberian abu batubarra terhadap pertumbuhan tanaman sengon (Parraseranthes falcataria (L.) Nielsen)
Abstrak: Pembakaran batubara menghasilkan uap yang digunakan untuk pembangkit listrik dan residu pembakaran seperti abu batubara yang terdiri dari abu terbang (fly ash) dan abu dasar (bottom ash), endapan gas desulfurisasi, dan limbah cair. Produksi limbah abu batubara yang tinggi dapat mencemari lingkungan. Penelitian ini dilakukan untuk mengetahui pengaruh abu batubara terhadap tanaman sengon di lapang dan ada tidaknya akumulasi logam berat pada daun sengon. Konsentrasi (b/b) abu batubara yang digunakan adalah 0% (kontrol), 0.1%, 0.2%, 0.4%, 0.8%, 1%, 2%, 3%, 4%, 5%, dan 10%. Analisis percobaan menggunakan rancangan acak lengkap yang terdiri dari 21 perlakuan dengan 3 ulangan. Pemberian abu batubara memberikan respon yang cukup baik pada riap diameter batang, riap tinggi tanaman, dan bobot kering tajuk, terutama pada abu dasar dengan konsentrasi < 2%, sedangkan untuk abu terbang dengan konsentrasi < 1%. Analisis jaringan pada daun sengon setelah diberikan abu terbang 0.4% mengandung unsur Fe 109.60 ppm, Mn 168.61 ppm, dan Zn 27.03 ppm, sedangkan abu dasar 0.1% mengandung unsur Fe 198.37 ppm, Mn 142.83 ppm, dan Zn 31.74 ppm. Sedangkan untuk Cu tidak terdeteksi. Berdasarkan analisis tanah dan jaringan daun tanaman sengon, pemberian abu batubara sebagai pupuk pada tanah latosol kurang baik karena dapat menyebabkan terjadinya akumulasi logam berat pada daun sengon, kandungannya berada di atas batas baku mutu kandungan logam berat air minum menurut Peraturan Menteri Kesehatan RI No.416/Men. Kes/Per/IX/1990, sehingga daun tersebut tidak baik digunakan untuk pakan ternak dan pupuk hijau, karena dapat membahayakan kesehatan manusia.
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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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