Judul: Pertumbuhan Kayu Putih (Melaleuca leucadendron Linn.) dan Longkida (Nauclea orientalis Linn.) pada Kondisi Tergenang Air Asam Tambang
Abstrak: Most of the coal mining operations in Indonesia use open mining systems that could expose sulfide minerals, so cause Acid Mine Drainage (AMD) surface if oxidized with O2 and met H2O. The problems experienced by each company which is active in mining coal, including PT Mandiri Intiperkasa. Handling of AMD that has been done is the provision of lime to neutralize the pH before being released into public waters. However, this can only be done if the company is still actively operating. Therefore, the AMD also need to be addressed passively, which will continue to work even though the company has stopped operating. Handling AMD passively conducted with make a pond sedimentation (settling pond) which is usually planted with grass tifa (Typha angustifolia). This technique is also known as wetland. Although this technique is capable of resolving the problem AMD, but can cause land becomes unproductive because overgrown grass species only. Therefore, it is necessary to add commercial tree types that can survive and grow well in a pool of AMD condition, so that someday can provide the added value of wood and non-wood. The selection of tree species based on the results of previous research that states that the kayu putih (Melaleuca leucadendron) and longkida (Nauclea orientalis) is able to survive in conditions of puddle water. The both types were also selected in this research, but the water used for flooding is the AMD. This research aims to know the viability and growth of kayu putih and longkida in a puddle of AMD, and the influence of both types are on the increase in pH AMD. The research conducted in the nursery PT Mandiri Intiperkasa, East Kalimantan in May–July 2011. The research conducted using Completely Randomized Design (CRD) by treatment with a combination of plants, namely tifa and kayu putih, tifa and longkida, as well as the tifa alone. Each experiment repeated three times, so there are nine units of the experiment. The observations of seedlings conducted during the four-week with the observed variables are the diameter and height growth, the pH of the AMD, plant dry weight, root shoot ratio, analysis of the vegetative organs of plants, and sludge analysis. The acquisition of data processed using Microsoft Excel and Minitab 14. The research states that each unit experiment increase in pH AMD, with first pH of 2.8 and at the end of the observation of up to 6.6. However, the increase in pH of the AMD was not influenced by the type of plant. The both types of trees, both kayu putih and longkida able to survive and to grow well for four weeks on puddle AMD condition.
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Judul: Cajeput Seedlings Endurances to Various Media  Contaminated by Acid Mine Drainage
Abstrak: Kayu putih (Melaleuca cajuputi) telah digunakan sebagai tanaman revegetasi lahan pascatambang. Pemberian bahan organik pada lahan pascatambang dapat memperbaiki kondisi fisik, kimia, dan biologi tanah. Kondisi tanah yang baik akan meningkatkan pertumbuhan dan ketahanan kayu putih pada kondisi tercemar air asam tambang. Penelitian ini bertujuan menganalisis campuran tanah dan kompos serta campuran tanah dan arang sekam terhadap ketahanan dan pertumbuhan bibit kayu putih yang tercemar air asam tambang serta menganalisis pengaruh tingkat konsentrasi cemaran air asam tambang terhadap ketahanan bibit kayu putih pada berbagai media tanam. Penelitian ini menggunakan Rancangan Acak Lengkap Faktorial dengan dua faktor yang terdiri dari konsentrasi air asam tambang dan jenis media tanam. Hasil penelitian ini menunjukkan bahwa tidak ada pengaruh interaksi antar faktor dan faktor tunggal konsentrasi air asam tambang terhadap persentase hidup, pertumbuhan tinggi, diameter, dan pertambahan jumlah daun, berat basah total, berat kering total, kadar air, dan panjang akar sedangkan media tanam yang digunakan memberikan pengaruh nyata terhadap persentase hidup, pertumbuhan tinggi, diameter, dan pertambahan jumlah daun., Cajeput (Melaleuca cajuputi) is widely used as a post-mining revegetation plant. The addition of organic matter to post-mining land can improve the physical, chemical, and biological conditions of the soil that lead on to increasing growth and endurance of cajeput in polluted land by acid mine drainage. This study aims to analyze the effect of compost mixture media and roasted husk mixture media to endurance and growth of cajeput seedling and also to analyze the effect of acid mine drainage concentration on the endurances of cajeput seedling on various media. This study used a completely randomized design with two factors consisting of acid mine drainage concentration and type of media. The results of this study indicate that the concentration of acid mine drainage has no significant effect on the growth of height, diameter, and number of leaves, also on total wet weight, total dry weight, moisture content, and root length while the type of media used has a significant effect on growth in height, diameter, and the number of leaves.
Keyword: acid mine drainage, compost, Melaleuca cajuputi, roasted husk

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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