Judul: paleorekonstruksi vegetasi dan lingkungan menggunakan fosil polen dan spora pada formasi Tapak Cekungan Banyumas kala plio-plistosen
Abstrak: Pollen and spores fossils have important information about the flora, vegetation, climate, and environment associated with processes and conditions during sedimentation process in the past.The main objective of this study was to disclose information, especially the ecology of palaeoflora, vegetation, and environmental deposition based on pollen and spores fossils, which were found in sedimentary rocks of the Banyumas Basin Tapak Formation.Totals of 166 sediment samples were prepared using modified palynology standard methods. Palynological analysis were carried out based on the habitus, habitat, total palynomorph and diagnostic pollen and spores fossils.This research found 72408 palynomorph fossils that consisted of 48570 pollen and spores fossils and 23838 marine fossils consisted of dynoflagellate cysts and foraminifera test lining (FTL). Pollen and spores fossils consisted of 76 types that were categorized into: 20 types categorized into species, 41 genus and 15 familia level. Based on habitus, 76 types of pollen and spores fossils were grouped into: 41 taxa (53.95%) of arboreal plants (AP),15 taxa (19.74%) of non arboreal plants (NAP), and 20 taxa (26.32%) of Pterydophytes.The presence of AP taxa were more dominant than the NAP taxa.This suggested that arboreal palaeoflora and vegetation were more developed in Banyumas Basin Tapak Formation. Pollen and spores fossils evidence indicated that the environment in the Banyumas Basin Tapak Formation was surrounded by mountainous morphology and the water flow system as pollen and spores media transport from mountainous to the transitional area through lowlands, freshwater, and mangrove swamps. The overall climate of Tapak Formation showed there was no clear differences between hot-wet and cold-dry climates.The presence of paleoflora taxa in Tapak Formation were relatively stable.The mean of similarity index ranged from 53.3 to 59.64%, which was categorized as high similarity criteria among sediment samples from each location, although the diversity was categorized from low to moderate. Generally, environmental deposition on Tapak Formation was a transitional area that was influenced by dynamic marine environment intensity.
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Judul: Studi Keanekaragaman dan Penyebaran Spasial Palem-Paleman (Arecaceae) di Hutan Lindung Gunung Slamet, Baturaden – Provinsi Jawa Tengah
Abstrak: Palm is one of interesting plant. It has been used for several needs and also a trading commodity. One of palms habitat is in Protected Forest of Mount Slamet. The threat of land conversion and forest fires is a problem in this area. The lack of information on the diversity, abundance and the distribution of palms make this area vulnerable and increated the possibility of unknown palms to go extinct. The purpose of the research is to describe the composition, diversity and the ecological distribution of palms and also analyzing the distribution of palms based on land and altitude. Research was conducted on May until June 2012, on two type of ecosystems natural forest and mix forest at Protected Forests of Mount Slamet. Data were collected using vegetation analysis method. Data of the palms were analyzed to obtain value of diversity, evenness and abundance of species. Spatial distribution Data were obtained from recording palms position. Thematic map of land and altitude was developed on processing the landsat map and divided them to different classes. Then, it was overlayed with palms point of occurence to produce a map of palms distribution based on land and altitude. Composition of palms on Protected Forests of Mount Slamet, on natural forest ecosystem found 12 species, and on mix forest ecosystem found 6 species. Distribution pattern of palms is clumped. The higest diversity of palms occurs on natural forest at 1.200 mdpl-1.300 mdpl with elevation 8-15 %, and mix forest at 900-1.000 mdpl with elevation 8-15%.
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Judul: Invers dari Matriks Tridiagonal Jacobi
Abstrak: Suatu matriks berukuran n×n dinamakan matriks tridiagonal jika untuk . Karya ilmiah ini memberikan algoritma yang mudah untuk menemukan invers ( dari matriks tridiagonal Jacobi yang simetrik dan nonsimetrik. Setiap elemen pada matriks tridiagonal ini adalah bilangan real. Terdapat 3 lema dan 2 teorema untuk menentukan . Lema pertama menunjukkan persamaan utama dalam membuktikan lema-lema dan teorema-teorema selanjutnya. Invers dari matriks yang simetrik dibuktikan oleh lema kedua yang menunjukkan elemen-elemen baris ke- dari . Selanjutnya, lema kedua dilengkapi dengan teorema pertama yang menunjukkan elemen-elemen dengan . Invers dari matriks yang nonsimetrik dibuktikan oleh lema ketiga yang menunjukkan elemen-elemen dengan dan elemen-elemen dengan dibuktikankan oleh teorema kedua.
Keyword: symmetric, nonsymmetric, matrix