Judul: Kontribusi ekosistem mangrove sebagai pemasok makanan ikan belanak (Liza subviridis)di perairan pantai utara konawe selatan Sulawesi Tenggara
Abstrak: The most important ecological functions of mangrove forests are nutrient cycles and energy flows. Mangrove litter fall in the water decomposed by microorganisms that produce nutrients (partly in the form of particles of litter (detritus)) are utilized by fish, shrimp and crabs as food (Bengen 2000; Bengen and Dutton 2004). Mangrove leaf is the largest part of litter primary production available to consumers contributed significantly to the food chain in the coastal fishery resources (Lee 1995; Ananda et al. 2007; Berg and McClaugherty 2008). The amount and quality of the mangrove detritus are based on the dominant mangrove species in the ecosystem. A kind of fish that make use of detritus in a mangrove ecosystem as a food source (energy) is the Greenback mullet (L.subviridis) from mugilidae family. This study aims to determine the contribution of mangrove forests as a detritus supplier served as food and energy sources of mullet (L. subviridis) on the north coast of South Konawe. The research was carried out for six months from May - October 2011 on the north coast of South Konawe Southeast Sulawesi, covering Landipo Estuaryne waters and Oyster Cape. Data collection of mangrove species at each stationwas was done using Line transect plots with a size of 10 mx 10 m for tree and 5m x 5m for the pups (Bengen 2001). Production of detritus derived from mangrove litter was carried out by inserting as many as 10 grams of leaf litter in litter bags measuring 20 cm x 30 cm made of nylon with a mesh size of 2 mm. Then, the bags were put into other plastic bags with small holes in some parts so the waste products of decomposition in the bag will not go out making calsulation easy. The fish were collected using varying mesh size of monofilament gill nets. Biological parameters measured were feeding habits, condition factor, hepto and Gonado somatic index. Macronutrients of the detritus were determined by proximate analysis. Variations in water chemistry and physics variables were analyzed using Principal Component Analysis (PCA). Distribution of detritus production between stations were analyzed using Correspondent Analysis (CA) (Lagendre and Lagendre 1983; Bengen 2000). The results showed that the total energy generated by Rhizophora apiculata detritus was greater than Sonneratia alba detritus. Detritus of Rhizophora apiculata contribute better to the condition factor, Gonado and Hepato-Somatic Index of mullet fish (Liza subviridis) than detritus of Sonneratia alba on the north coast of South Konawe.
Keyword: Southeast Sulawesi, Mangrove Ecosystems, Liza subviridis

Judul: Model Dinamik Pengelolaan Ekosistem Mangrove yang Berkelanjutan di Muara Sungai Wulan Demak
Abstrak: Mangrove serves as spawning grounds and nursery grounds for various species of fish, shellfish and other species. Mangrove litter such as leaves, twigs and other biomass fall to become food sources for organisme in the water and nutrients that determine the productivity of marine fisheries. However, the benefits and functions of mangrove are not fully understood because they are not seen directly and within a short time. Difficulty in assessing the benefits of mangrove causes local governments and communities do not consider it in management. So that the mangrove ecosystem is converted to multiple uses such as aquaculture. The purposes of this study were to calculate the value of the potential benefits of the litter of mangrove fisheries donations, determine the level of utilization of mangrove ecosystems, and create a dynamic model of mangrove management for sustainable fisheries. This study was conducted in February-April 2013 in the mangrove area, Wulan estuary, Demak, Central Java. Primary data were characteristics of mangrove, physical and chemical parameters of the environment, the primary productivity of mangrove ecosystems, socio-economic data of fishermen and farmers associated with the utilization of mangrove ecosystems. Secondary data were number of fishermen, number of farmer, pond and mangrove area. The methods of analysis were analysis of the relationship of mangrove characteristics and enviromental parameters, analysis of important value index and diversity indices, analysis of primary productivity, and analysis of mangrove area changes, and analysis of the use value with the consumer surplus approach. Data were collected through sampling and direct measurement in the field, followed by measurements in the laboratory. Then the processed data was used in making management model. The results showed an average production of mangrove litter 4,52 g/m²/year or 16.508,95 kg per hectare per year. Litter was expected to contribute to the fishery potential of 1.405,25 kg per hectare per year. The economic value of mangrove ecosystem for fisheries was Rp538.345.015,00 per hectare per year. Economic value for the use of ponds was Rp20.417.269,00 per hectare per year. Of the model developed shows that the addition of mangrove least 5 ha / year to maintain sustainable use of fisheries at Wulan Estuary Demak. So that the protection of the mangrove ecosystem is expected to maintain sustainable use of fisheries for the surrounding community.
Keyword: mangrove litter, consumer surplus, sustainability

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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