Judul: Komposisi Vegetasi dan Potensi Tumbuhan Obat di Hutan Kerangas Kabupaten Belitung Timur Provinsi Kepulauan Bangka Belitung
Abstrak: Heath forest on East Belitung is thought to have a diversity of plant species that can be used for medications. However, the information about it has not been revealed yet. Therefore, research about composition of vegetation and potential medicinal plants in the heath forest is necessary. This research was conducted in the primay heath forest (Rimba), secondary heath forest (Bebak) and particular heath forest (Padang) at East Belitung on July to Agustus 2011. The collected data includes species of plants (local name and scientific name), species of plants used medicine and part of plants that is used for medicine. Methods that is used to collect the data is the analysis of vegetation and interview method. Analysis vegetation was done by using combination of line and compartment method. The number of lines in each forest type are 10 with each line size is 10 m × 100 m and the distance between the lines is 50 m. The research results 224 species of plants in the heath forest obtained from different habitus and growth rates. Species with the highest value of importance on seedling, bush/shrub, herbaceous, liana, rattan and pandan is the samak (Syzygium lepidocarpa) amounted to 20.2% in the primary heath forest, pulas (Guioa pleuropteris) amounted to 12.57% in the secondary heath forest and kucai padang (Fimbristylis sp.) amounted to 51.14% in the particular heath forest. Species with the highest value of important on sapling is betor belulang (Calophyllum lanigerum) amounted to 17.27% in the primary heath forest, kiras (Garcinia hombroniana) amounted to 21.50% in the secondary heath forest and sekuncong (Leptospermum flavescens) amounted to 88.46% in the particular heath forest. Species with the highest value of important on tree is seru (Schima wallichii) amounted to 53.36% in primary heath forest, seru (Schima wallichii) amounted to 103% in secondary heath forest and sekuncong (Leptospermum flavescens) amounted to 180.2% in the particular heath forest. The number of medicinal plant species are identified based on knowledge of local communities as much as 101 species. Plant family which were most widely utilized is Myrtaceae. Tree is the most common habitus of medicinal plant to be used. The part of plants which is widely used is root and the most numerous group of diseases cured with medicinal plant is diseases of body resilience system (fever). Composition of vegetation in heath forest is potential as a germ plasm reserve of medicinal plants in Indonesia. Heath forest resources conservation can support sustainability of species and benefits to community around the forest.
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Judul: Kajian potensi fitokimia dari hutan di blok kebon Segoro-Ngaleng Resort Bande Alit Taman Nasional Meru Betiri Jawa Timur
Abstrak: Tumbuhan merupakan salah satu sumberdaya hayati yang dapat dimanfaatkan sebagai bahan baku obat. Indonesia dengan hutan tropika yang keanekaragaman jenisnya tinggi sangat berpotensi untuk menghasilkan bahan baku obat-obatan. Taman Nasional Meru Betiri telah dikenal memiliki beberapa jenis yang telah dipakai oleh penduduk sekitar hutan sebagai obat-obatan tradisional seperti Piper retrofractum (cabe jawa), Terminalia belerica (Joho lawe). Pangium edule (Pakem), Parkia roxburghii (kedawung) dan Piper cubeba (kemukus). Selain itu diduga Taman Nasional Meru Betiri masih menyimpan keanekaragaman jenis yang berpotensi sebagai bahan obat. Permintaan obat yang semakin meningkat yang bahan bakunya berasal dari tumbuhan hutan apabila tanpa diikuti oleh budidaya dan pencarian jenis-jenis baru yang berpotensi bahan obat akan mengakibatkan kelangkaan jenis jenis tertentu yang berkhasiat obat yang akan mengancam kelestarian jenis tersebut. - Penelitian ini bertujuan untuk mengetahui jenis-jenis yang berpotensi bahan obat di daerah-daerah konsentrasi tumbuhan obat Kebon segoro, Manung, Tanjung Pring dan Ngaleng Resort Bandealit Taman Nasional Meru Betiri. Penelitian dimulai dari bulan April-Mei kemudian dilanjutkan bulan September - November 1994. Data diambil dengan meletakkan petak ukur berbentuk jalur berpetak dengan metode sistematik sampling di Daerah konsentrasi tumbuhan obat Kebon segoro, Manung, Tanjung pring dan Ngaleng dengan jarak 500 m untuk tipe hutan hujan Dataran rendah dan 100 m untuk tipe hutan Pantai. Selanjutnya mendapatkan indek nilai penting, keragaman jenis, kesamaan komunitas dan pola penyebaran. Untuk mengetahui senyawa kimia yang dikandung oleh suatu jenis tumbuhan dilakukan pengujian fitokimia melalui uji alkaloid, uji /triterpenoid. flavonoid, uji saponin, uji steroid Dari analisis vegetasi yang dimulai dari Kebon segoro, Manung, Tanjung pring, Ngaleng diperoleh 93 jenis tumbuhan pada tingkat pohon, 54 jenis pada tingkat tiang, 59 jenis pada tingkat pancang, 159 jenis pada tingkat semai dan tumbuhan bawah serta 42 jenis epifit dan liana…dst
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Judul: Approximation of the Median of Poisson Distribution Using the Relation of Poisson-Gamma Distribution
Abstrak: A major drawback of median is that median cannot usually be defined in closed form, even in the cases where their distribution functions are known. This study gives an approximation of the closed form for the median of the Poisson distribution by using the relation of Poisson-Gamma distribution. The approximation uses elementary techniques based on the monotonicity of certain sequences involving tail probabilities of the Poisson distribution and the Central Limit Theorem. Furthermore, a closed form expression for the mean absolute deviation 􀜧|􀜰􀰒 􀵆 􀜯􀝁􀝀􁈺􀜰􀰒􁈻| is also studied. The median is relevant because of the fact that it minimizes the mean absolute deviation of a Poisson random variable (􀜰􀰒􁈻 by considering median as central tendency.
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