Judul: Regenerasi nutrien akibat bioturbasi di kawasan reklamasi mangrove Muara Angke Kapuk – Jakarta
Abstrak: Bioturbation is an activity of digging, crawling, and eating sediment by benthic and able to give the effect of nutrient regeneration with the highest regeneration activity conducted by digging. Those activities presumably as one of water column nutrient sources in mangrove reclaimed of Muara Angke Kapuk which affected by waste and heavy metal from Cengkareng drain. This study aims to investigate the relevance of nutrients regeneration (fluxes) and bioturbation activity that occur in mangrove reclaimed of Muara Angke Kapuk through identifying of benthic bioturbation physical characteristics using resin cast method, measuring the nutrient profile in the pore water of bioturbation and non bioturbation regions, as well as analyzing nutrients fluxes behavior using sensitivity analysis of QUAL2K model. The observations results show the presence of four physical characteristics of the bioturbation burrows: single, Ushaped, Y-shaped, and complex; with the dominance of a single character. The existence of bioturbation burrows play an important role in the sediment, particularly the inversely vertical concentration profile and nutrients fluxes on bioturbation and non bioturbation regions. The fluxes in bioturbation region are mainly controlled by porosity as dominant parameter, followed by phytoplankton (chlorophyll a) abundance, nutrients concentration and DO parameters.
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Judul: The effect of waste on chlorophyll content of leaves and regeneration of mangrove forest at angke kapuk protection forest, north jakarta2
Abstrak: Ekosistem mangrove merupakan peralihan antara daratan dan lautan. Saat ini hutan mangrove di kawasan lindung Angke Kapuk, Jakarta Utara terdegradasi diantaranya karena tumpukan sampah yang masuk ke kawasan hutan tersebut. Sehubungan dengan itu, penelitian ini dilaksanakan dengan tujuan untuk mengkaji sejauh mana pengaruh keberadaan sampah terhadap kandungan klorofil daun pohon mangrove dan regenerasi hutan mangrove di kawasan lindung Angke Kapuk. Hasil penelitian menunjukkan bahwa keberadaan sampah tidak berpengaruh terhadap kandungan klorofil daun pohon mangrove, tetapi berpengaruh terhadap regenerasi hutan mangrove. Hal ini ditunjukkan dengan kerapatan anakan pohon (semai) pada kawasan hutan tidak ada sampah lebih besar dibandingkan kerapatan anakan mangrove di kawasan sedikit sampah dan kawasan banyak sampah., Mangrove ecosystem is a transition ecosystem between land and sea. Currently the mangrove forests at Angke Kapuk Protection Forest, North Jakarta has been degraded by large amount waste. In connection with this situation, the forest research was carried out with the aim to consider the effect of waste existence on the chlorophyll content of tree’s leaf and the regeneration of mangrove forests in Angke Kapuk Protection Forest. The results showed that the existence of the waste has no effect on the chlorophyll content of leaves, but it has significant by effect on the regeneration of mangrove forest. This is shown with a density of mangrove seedlings in the less waste-occupied mangrove area is bigger than that of medium and high waste-occupied mangrove areas.
Keyword: ekosistem mangrove, kandungan klorofil daun, regenerasi hutan, sampah

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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