Judul: Rekrutmen Karang pada Substrat Batu di Gosong Pramuka, Kepulauan Seribu DKI Jakarta
Abstrak: Gosong Pramuka is an area of coral reefs in the center of the Kepulauan Seribu region economy. The existence of the stony substrate around Gosong Pramuka as a potential habitat for coral larval settlement. Research aims to determine the recruitment of coral stony substrate in the Gosong Pramuka, Kepulauan Seribu. Research was conducted from April to June 2013 at Gosong Pramuka, comprising four stations: Exposed I, Exposed II, Sheltered I, and Sheltered II. Observations were conducted by observing all surface of stony substrate for coral recruits. Each coral recruits were vertically photographed using underwater camera with macro setting, thus identified until genus level. Images of coral recruit were processed by Image J to measure coral diameter and width. There were 95 colonies of coral recruits with the largest number of colony observed at Station Exposed I (35 colonies) belonging to Acropora and Porites. Lifeform of coral recruit for Acropora comprised of branching, digitate, tabulate and encrusting, while for Porites was massive and submassive. Average width of coral recruit was 25-50 cm2, while average diameter was 9-12 cm. Average index of coral health was 2-3, referring to CoralWatch method, indicating stressed colonies. Density of coral recruit for Station Exposed I was 0.22 colony/m2, Sheltered I 0.11 colony/m2, Exposed II 0.13 colony /m2 and 0.11 colony /m2 at Sheltered II. Correspondence analysis revealed that the presence of Porites coral recruit was influenced by depth, salinity, pH, temperature, while Acropora by distance from reef/stone bottom. Average diameter and width of coral recruits were closely associated with orthophosphate. Diameter of coral recruit was closely affecting the coral width.
Keyword: stony substrate., Porites, Gosong Pramuka, coral recruit, Acropora

Judul: Rekrutmen dan Kesehatan Karang (Scleractinia) pada Substrat Batu di Perairan Gosong Pramuka, Kepulauan Seribu, DKI Jakarta.
Abstrak: Rekrutmen karang merupakan proses dan peristiwa kemunculan individu-individu karang muda yang dihasilkan melalui reproduksi, kemudian menempel pada substrat dan menjadi bagian dari komunitas terumbu. Keberadaan substrat batu di sekeliling Gosong Pramuka dapat dijadikan habitat untuk penempelan larva karang. Penelitian ini bertujuan untuk mengkaji rekrutmen karang berdasarkan genus, bentuk pertumbuhan, variasi ukuran, kepadatan, dan kesehatan karang rekrut yang terdapat di bagian terlindung maupun bagian yang tidak terlindung pada substrat batu di Gosong Pramuka, Kepulauan Seribu, DKI Jakarta. Penelitian dilakukan mulai bulan April hingga Juni 2014 bertempat di Gosong Pramuka, Kepulauan Seribu, DKI Jakarta yang terdiri atas empat stasiun : STP 1, STP 2, STL 1, dan STL 2. Setiap karang rekrut difoto secara tegak lurus menggunakan kamera bawah air dengan pengaturan makro, setelah itu diidentifikasi genus, bentuk pertumbuhan, variasi ukuran, kepadatan, dan kesehatannya. Pengolahan foto karang rekrut menggunakan perangkat lunak Image J untuk mendapatkan ukuran dimeter dan luas karang. Genus yang ditemukan pada stasiun penelitian ialah Porites, Acropora, Goniastrea, Montipora, Pavona, Caulastrea, Favia, dan Pocillopora. Bentuk pertumbuhan terdiri dari Acropora (encrusting, branching, dan tabulate) dan non Acropora (encrusting, submassive, massive, branching, dan foliose). Rata-rata diameter karang rekrut baik yang hidup maupun yang mati (DCA) ialah 6-10 cm termasuk kategori kecil dan rata-rata luas karang rekrut adalah 0-25 cm². Kesehatan karang rekrut berdasarkan CoralWatch tergolong baik. Adapun gangguan kesehatan yang ditemukan ialah sedimentasi, white plague, growth anomaly, competition overgrowth,dan focal bleaching.
Keyword: CoralWatch, gosong Pramuka, karang, rekrutmen

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.
Keyword: