Judul: Amelioration of Compost and Coal Ash on an Ultisol of Pineapple Plantation: Temporal Dynamics of Soil Chemical Properties
Abstrak: Kendala utama sifat kimia Ultisols untuk pertanian meliputi rendahnya pH, bahan organik, KTK, dan ketersediaan hara. Penelitian ini bertujuan mengevaluasi dinamika temporal sifat kimia tanah pada 0, 2, 6, 9, dan 10 bulan setelah ameliorasi (BSA) kompos dan abu batu bara (FABA) pada Ultisol di lahan perkebunan nanas. Penelitian terdiri dari percobaan lapang dan percobaan perkolasi di rumah kaca dengan RAL, keduanya terdiri dari 6 taraf perlakuan yaitu kontrol, kompos 50 ton/ha (KT 50), Kompos+FABA 50 ton/ha (KFT 50), KFA 25, KFA 15, dan KFA 5, T= tebar dan A=alur. Selain amelioran ini, tanah juga dipupuk lengkap. Analisis dengan metode rutin dilakukan terhadap sifat-sifat kimia tanah lapisan 0-20 cm pada 0 dan 2 BSA dari percobaan lapang, pada 9 dan 10 BSA dari percobaan perkolasi, dan pada 6 BSA berdasarkan ekstrapolasi. Perlakuan berpengaruh sangat nyata. Secara umum, sifat-sifat kimia tanah terbaik diperoleh pada perlakuan KFA 25. Kadar hara semakin turun dengan waktu akibat proses pencucian. Pada perlakuan terbaik 10 BSA, kadar C-organik, N-total dan KTK tanah lebih tinggi dari kadar awal meskipun masih tergolong rendah, sedangkan P-tersedia juga lebih tinggi dari kadar awal dan tetap tergolong sangat tinggi. Namun, kadar K-dd, Cadd, dan Mg-dd lebih rendah dari kadar awal dan tetap tergolong sangat rendah. Untuk mempertahankan produktivitas tanaman, maka disarankan untuk memberikan pupuk N dan K serta ameliorasi kompos dan FABA pada 10 BSA., The main chemical constraints of Ultisols for agriculture include low soil pH, organic matter, CEC, and nutrients availability. This study aims to evaluate temporal dynamics of soil chemical properties at 0, 2, 6, 9, and 10 months after amelioration (MAA) of compost and coal ash (FABA) on an Ultisol of pineapple plantation. The study consisted of field and greenhouse percolation experiments, both with CRD consisting of control, 50 ton/ha compost (CB 50), 50 tons/ha compost+FABA (CFB 50), CFR 25, CFR 15, and CFR 5 treatment levels, where B = broadcast and R = row application. Besides, the soil was completely fertilized. Chemical analyses were done using routine methods on soil samples of 0-20 cm layer at 0 and 2, 9 and 10, and 6 MAA, respectively from the field experiment, from the percolation experiment, and based on extrapolation. The treatment’s effects were very significant. In general, the best results were obtained at CFR 25 treatment level. The nutrient status decreased with time due to leaching processes. From the best treatment at 10 MAA, compared to the corresponding initial status, soil organic-C, total-N, and CEC were higher than, although still classified as low, whilst P-availability was also higher than, but still classified as very high. However, the soil exchangeable-K, -Ca, and -Mg were lower than the initial levels and still classified as very low. To maintain plant productivity, it is suggested to apply supplementary N and K fertilizers and compost and FABA ameliorants at 10 MMA.
Keyword: ameliorant, broadcast, leaching, percolation, row

Judul: Pengaruh Penambahan FABA dan Lignit dalam Kompos terhadap Sifat Kimia dan Pertumbuhan Nanas (Ananas comosus) pada Ultisol
Abstrak: Degradasi pada Ultisol disebabkan oleh kegiatan monokultur secara terus-menerus dicirikan dengan pH, kadar bahan organik, dan unsur hara rendah, serta kadar aluminium yang tinggi. Untuk mengatasi degradasi Ultisol demikian, digunakan amelioran berupa kompos. Namun, penggunaan kompos sebagai amelioran belum mendapatkan hasil yang optimal terhadap peningkatan kualitas Ultisol. Kompos kurang dalam menyediakan unsur hara, sehingga diperlukan penambahan fly ash dan bottom ash (FABA) maupun lignit dalam kompos. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh penambahan FABA dan lignit dalam kompos untuk memperbaiki kualitas Ultisol yang ditanami nanas, serta mengetahui pengaruh penambahan FABA dan lignit dalam kompos terhadap pertumbuhan serta kadar hara dalam daun nanas. Perlakuan dalam penelitian ini disusun menggunakan rancangan petak terbagi dalam rancangan acak kelompok dengan petak utama adalah teknik aplikasi palir (P) dan tebar (T) serta anak petak adalah kompos 100% (K), kompos 75%+FABA 25% (KF), dan kompos 70%+FABA 20%+ lignit 10% (KFL). Perbandingan fly ash dan bottom ash adalah 6:1, serta bottom ash dan lignit telah lolos ayakan 1 cm. Amelioran diberikan dengan dosis 50 ton ha-1. Tanaman uji yang digunakan adalah bibit nanas klon GP3 sucker kelas besar dan dilaksanakan di blok 86-A kebun PT. Great Giant Pineapple. Hasil penelitian ini menunjukkan bahwa penambahan FABA dan lignit dalam kompos meningkatkan pH, karbon organik, kejenuhan basa, kalsium-, magnesium-, natrium-dapat dipertukarkan, dan seng serta menurunkan kadar aluminium dapat dipertukarkan pada Ultisol. Penambahan FABA dan lignit dalam kompos juga meningkatkan kadar kalsium, belerang, dan seng dalam daun. Disamping itu, penambahan FABA dalam kompos meningkatkan D-leaf index tanaman nanas. Pemberian amelioran lebih efektif jika diaplikasikan secara palir dibandingkan dengan tebar. Penggunaan FABA dalam kompos sebagai amelioran diharapkan dapat meningkatkan kualitas Ultisol terdegradasi dan produktivitas tanaman serta mengurangi dosis kompos yang digunakan pada tanaman nanas., Degradation of Ultisol is caused by continuous monoculture activities and is characterized by low pH, organic matter, nutrient content, and high aluminium contents. In response to such Ultisol degradation, ameliorants in the form of compost are used. However, using compost as an ameliorant has yet to obtain optimal results toward improving the Ultisol quality. The lack of ability of compost to supply nutrients is because the nutrients in compost are easily lost due to leaching, so it is necessary to add coal ash consisting of fly ash and bottom ash (FABA) also lignite in compost. This study aimed to determine the effect of compost-enriched with FABA and Lignite to improve the Ultisol's quality planted with pineapple and also on its growth and nutrient levels in the leaves. The treatments in this study were arranged using a split plots design in a randomized block design, with the main plot being the application technique of row (P) and spread (T). The subplots were 100% compost (K), 75% compost + 25% FABA (KF), and 70% compost + 20% FABA + 10% lignite (KFL). The ratio of fly ash and bottom ash was 6:1, and bottom ash and lignite had passed a 1 cm sieve. Ameliorants were applied at a dose of 50 tons ha-1. The test plants used were pineapple seedlings of large class clones GP-3 sucker and were carried
Keyword: Compost, Faba, Lignite, Pineapple, Ultisol

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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