Judul: Ecosystem characteristics of mangrove at small islands of wakatobi national park, Southeast Sulawesi Province
Abstrak: The study was aimed to elaborate structure and composition of mangrove vegetation and to examine relationship between mangrove vegetation pattern and abiotic factors in Kaledupa, Derawa and Hoga Islands in Wakatobi National Park. Sampling of vegetation was done continuously across mangrove community, starting from front (seaward) vegetation formation to the inner formation (landward) by line transect and plot methods. Structure and composition of were determined through vegetation analysis with parameter including frequency, relative frequency, density, relative density, dominance, relative dominance, importance value, zonation determination, natural regeneration, distribution of stem diameter (diameter et breast high) and status of mangrove community. Species diversity was analyzed using Shannon Wiener Index. Analysis of Variance (ANOVA) was used to see difference of abiotic factors among islands and Duncan-test to examine abiotic factors having significantly different responses (p = 0,05). 20 species of true mangrove were found and the largest species was found in Kaledupa Island. Distribution of mangrove vegetation species in the study areas was supposed to be related to wave protection, siltation, and freshwater input. The highest total individual density was found in Kaledupa Island and the lowest one was found in Derawa Island. Species of Bruguiera gymnorrhiza (L.) Lamk., and Rhizophora mucronata Lamk with the highest density was found in Derawa Island. Diversity Index of mangrove vegetation species was chategorized as low. Species having a good natural regeneration was found at Ceriops tagal (Perr.) C.B. Rob., and Ceriops decandra (Griff.) Kaledupa Island, and Osbornia octodonta F.v.M Hoga Island. For genus of Rhizophora besides reproduce through seed/propagule, it is also reproduce vegetatively through branches. Environmental factors of soil having significant relationship with the community pattern in this study were: pH, Kalium (available), and Salinity. Content of soil organic material, Nitrogen (total), Phosphate (available) and soil texture (silt, clay and sand) did not show a significant relationship with the community pattern of mangrove vegetation community. Zonation pattern of mangrove vegetation was only found in Kaledupa Island. Mangrove zonation Kaledupa Island consisted of four zones. Successively, from the seaward to the landward were Rhizophora mucronata Lamk., Rhizophora apiculata Bl., Ceriops tagal (Perr.) C.B. Rob., Ceriops decandra (Griff.) Ding Hou zone. Height of seawater inundation was factor having significant relationship with zonation pattern. Distribution of diameter classes was chategorized as J-shaped graph model. Status of mangrove community in this national park was classified as damaged class due to human activities.
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Judul: Degradasi Ekosistem Mangrove di Pulau Kaledupa Taman Nasional Wakatobi
Abstrak: Mangrove ecosystem is one type of natural resource conservation target in Wakatobi National Park. Mangrove provides various types of products and environmental protection services such as protection against abrasion, sea water intrusion control, reducing the strong winds, reducing high and flow velocity waveform, recreation and cleaning water from pollutants. Because of he mangrove ecosystem have important functions, degradation in these ecosystem must be properly managed in order functions can be used optimally. One method that is commonly used to study the degradation of mangrove ecosystems is Geographic Information System. Aims of this study were to analyze the level of deforestation and degradation of mangrove, the mangrove species composition and diversity, the correlation between body size mangrove crab (Scylla serrata) with the degradation level of mangrove and to formulate the causes as well as efforts to control the degradation of mangrove ecosystems in Kaledupa Island, Wakatobi National Park. The research was conducted in July 2014 at Kaledupa Island, National Park Wakatobi, Southeast Sulawesi Province. Field data collection is done by taking coordinate points and satellite imagery, vegetation analysis, measurements of mangrove crab morphometric and interview. The results of study showed since declared a national park in 1996, there has been a mangrove deforestation by 214.04 ha untill 2014. The largest mangrove deforestation occurred in Lewuto Village, while smallest deforestation in Tanomeha Village. SIG method showed that was damaged mangrove area in Kaledupa increased from 39.12 ha in 1996 to 41.33 ha in 2014. As for the undamaged mangrove area decline of 938.91 ha in 1996 to 722.66 ha in 2014. Based on the teristris method, mangrove ecosystem in Kaledupa are in a damaged condition. Mangrove communities in Kaledupa composed by eight species. Mangrove species with the highest IVI in four sampling villages varied, namely Rhizophora apiculata Bl. (Tanomeha), Rhizophora mucronata Lamk. (Balasuna), Ceriops tagal (Perr.) B. C. Rob. (Lewuto) and Sonneratia alba Smith (Horuo- Tampara). Mangrove damage level had a negative correlation with morphometric of mud crab (Scylla serrata). Causal factors of degradation include economic factors, education and skills, and weak of supervision of the authorities. Strategies to control the mangrove ecosystems degradation in Kaledupa Island were to utilize mangrove ecosystem status as a conservation area to preserve the mangrove so the potential to be used as an attractive eco-tourism area and should empower communities to provide mangrove seedlings through the establishment of nurseries.
Keyword: control strategies, degradation, deforestation, mangrove ecosystems, mud crab

Judul: Pemanasan Sekunder Reaksi Fusi Plasma dengan Menggunakan Radio Frequency
Abstrak: Plasma merupakan bentuk ke-empat dari materi setelah padat, cair dan gas yang terbentuk dari proses ionisasi gas. Plasma dapat digunakan dalam reaksi fusi, yaitu reaksi penggabungan dua inti atom ringan menjadi inti atom yang lebih berat sambil melepaskan energi. Untuk mendapatkan energi dari reaksi fusi, inti yang akan direaksikan harus dipanaskan pada temperatur yang sangat ekstrem tingginya. Salah satu cara agar dapat mencapai kondisi ini adalah memberikan pemanasan tambahan atau pemanasan sekunder kepada plasma dalam reaksi fusi tersebut. Nilai daya serap rata-rata ion Deuterium yang sesuai dengan selang nilai daya dari data ITER adalah daya yang menggunakan frekuensi 50 MHz sampai dengan 60 MHz. Dengan menggunakan frekuensi 60 Hz diperoleh nilai daya rata-rata yang diserap sebesar 1,235.10-12 W.
Keyword: gelombang radio, pemanasan sekunder, plasma, reaksi fusi