Judul: Keanekaragaman, Struktur Populasi dan Pola Sebaran Syzygium di Gunung Baung Jawa Timur
Abstrak: The research of Syzygium diversity, its population structure and the distribution patterns were conducted in Gunung Baung Nature Park, East Java. A total of five block locations, each comprising five transect sections, were purposively selected to obtain data of the taxon diversity, population stucture and distribution patterns. The importance value index, the individual number of each stratum (stage class) (i.e. seedlings, saplings, poles and trees) and variance-to-mean ratio were calculated. The principal component analysis, cluster analysis, multiple linear regressions and canonical correspondence analysis were performed to determine the relationships between abiotic and biotic factors in regard with the presence of Syzygium. There were six species of Syzygium in Gunung Baung, Pasuruan, namely S. cumini, S. polyanthum, S. littorale, S. pycnanthum, S. racemosum, and S. samarangense. The population structure of Syzygium varied considerably, only S. pycnanthum and S. racemosum had an ideal structure. This was presumably due to some problems faced by the genus in the process of regeneration, especially during the seedling phase. The distribution patterns of the Syzygium members were generally grouped prefering fertile sites on the slopes. Altitude and the number of bamboo clumps became the determinant (influencing) variables affecting significantly the existence of Syzygium in this mount.
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Judul: Ekologi dan Bioprospeksi Bambu di Kawasan Taman Wisata Alam Gunung Baung Pasuruan Jawa Timur
Abstrak: Bamboo is one of plant taxa comprising various species with high economic potential. Bamboo is a member of Bambusoideae of the Poaceae family. There are 1250 bamboo species in the world, 135 of them are in Indonesia. Not all bamboo species are well known, and only some of them can be found in Java Island. Land use changes reduce bamboo natural habitats in Indonesia. One of the bamboo forests in East Java is found at a conservation area namely Mount Baung Natural Park. The information of bamboo diversity, population structure and the relationship between bamboo and its biotic and abiotic factors in Mount Baung Natural Park is not well known. The aims of the research were to study the ecology of bamboo, the relationship between bamboo growth and its biotic and abiotic factors, and the bio-prospection aspect of this taxon in Mount Baung Natural Park, Pasuruan, East Java. This research was carried out at four different locations from September 2011 to Mei 2012. Those locations were Preserved Area, Rehabilitation Area, Limited Usage Area, and Intensive Usage Area. Data collection was conducted by analyzing the bamboo populations using sampled plots along the transects that were determined by stratified random samplings within four purposive sampled areas. The collected botanical data consisted of the bamboo scientific names, the number of clumps per plot and the diameter of clumps. The environmental data consisted of altitude, solar radiation, temperature-humidity, and soil pH. Soil samples were analyzed at the Soil Chemical Laboratory, Center for Research of Land Resources, Bogor. The abundances and densities of bamboo expressed an importance value index, namely the resultant of the sum of Relative Density, Relative Frequency, and Relative Dominance. The determination of habitat characteristics (i.e. determining the most related factors in relation to the presence of bamboo in their community) were analyzed by statistical correlations using the software STATISTICA Minitab 14. The principal component analysis (PCA) and cluster analysis were performed to determine relationships between abiotic/biotic components and bamboo’s occurrences. Canonical Correspondence Analysis (CCA) was used to determine component relationships. Cluster analysis was used to analyze the similarity of the environmental conditions of the bamboo habitat. Index Cultural Significance (ICS) was performed to determine the bamboo bio-prospecting of bamboo. There were seven species of bamboo in Mount Baung Natural Park, Pasuruan, namely Bambusa blumeana, Bambusa vulgaris, Dendrocalamus asper, Schizostachyum iraten, Gigantochloa apus, Gigantochloa atter and Dinochloa matmat. D. matmat was not described detail in this These due to the very limited number ( < 1%) of individual occurence. Among the six bamboo species, B. blumeana possessed nearly ideal population structure. Bambusa blumeana had the highest important value index 127,97%. The structure of bamboo population was classified based on the clump diameter classes which were: A (< 5 m), B (5-10 m) and C (> 10 m). Based on this category, the bamboo in Mount Baung Natural Park belonged to A phase class. Based on the soil analysis, the location had good soil characteristics and was feasible for bamboo growth, namely silty clay loam, medium CEC (Cation Exchange Capacity) ranging from 10,90 to 18,52
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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