Judul: Keanekaragaman Jenis Ular di Areal Perkebunan Sawit PT Sukses Tani Nusasubur Kalimantan Timur
Abstrak: Ecologically, snake has been known to functions as biological pest control. The aim of this research is to assess snake diversity in oil palm plantation area of PT Sukses Tani Nusasubur in East Kalimantan. The survey found 22 individual of snakes consisting of eight species in four families. Xenopeltidae (1 species), Colubridae (5 types), Pythonidae (1 species), and Elapidae (1 species). Two species of snakes, Naja sumatrana and Python reticulatus, is include in Appendix II of CITES. Snake species diversity is highest on karst habitats with Shanon Index of diversity of 1.74 and the lowest in the secondary forest habitat type with an index value of 0. Evenness index within oil-palm plantation are moderate, with low dominance of Dendrelaphis pictus. Highest level of evenness is found in karst habitat and lowest in the secondary forest habitat. Food habits analysis were only conducted for selected species with limited number of snake. The result only found reptile and amphibian as food, but unable to showed the function of snake as rodent control
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Judul: Keanekaragaman Jenis Reptil Pada Berbagai Tipe Habitat Di Perkebunan Sawit Kabupaten Kotawaringin Barat Kalimantan Tengah
Abstrak: Kelapa sawit mengalami perluasan lahan paling pesat di dunia. Reptil sangat rentan terhadap perubahan habitat dan kerusakan hutan oleh karena itu penelitian ini diharapkan dapat menggambarkan keanekaragaman jenis reptil di berbagai habitat di dalam perkebunan sawit. Metode yang digunakan adalah Visual Encounter Survey (VES) berdasarkan waktu dan transek serta pemasangan jebakan lem yang berlangsung pada bulan Mei-Juni 2016. Total jenis yang ditemukan yaitu 22 jenis dari 12 famili, dengan 2 jenis di antaranya yaitu Notochelys platynota dan Siebenrockiella crassicollis termasuk ke dalam kategori VU (Vulnerable) pada daftar merah IUCN. Indeks keanekaragaman jenis tertinggi pada kawasan konservasi hutan sekunder lahan basah dan hutan sekunder lahan kering, masing-masing sebesar 1.95 sekaligus merupakan habitat dengan kemerataan jenis tertinggi (E=1) yang menunjukkan seluruh jenis yang ditemukan menyebar merata.
Keyword: konservasi, reptil, sawit, Kalimantan

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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