Judul: Kajian Ekologi Ungko (Hylobates agilis agilis) di Taman Nasional Batang Gadis Sumatera Utara
Abstrak: Ungko/mountain agile gibbon (Hylobates agilis agilis is one of Sumatera endemic gibbon is considered a near threatened spesies. The aim of this research was study the ecology of mountain agile gibbon (ungko) at Batang Gadis Nasional Park.
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Judul: Struktur dan Komposisi Jenis Vegetasi pada Habitat Ungko (Hylobates agilis F.Cuvier 1821) dan Siamang (Symphalangus syndactylus Gloger 1841) di Stasiun Penelitian Hutan Batang Toru Bagian Barat, Sumatera Utara
Abstrak: Gibbon (Hylobates agiliis) and siamang (Symphalangus syndactylus) are the two kinds of Hylobatidae species that inhabit a Sumatera’s forest. One of the Sumatera’s forest region, which was sympatrycally inhabited by the two kinds of Hylobatide, is Western Batang Toru Forest, North Sumatera Province. Gibbon and siamang are arboreal primates that lived exclusively at the forest canopies, and they are highly depended on their habitat’s vegetation condition. This research objectives were (1) to describe the structure, composition and diversity of the trees speciesat the gibbon and siamang habitat and (2) to identify a use of the vegetation by the gibbon and siamang in their habitat. There were three types of the forest in Western Batang Toru Forest namely transitory hill-montane forest formation (FHHM), peat forest formation (FHG) and upper Dipterocarpaceae forest formation (FHDA). All of the forest types in the gibbon and siamang’s habitat had high Shannon-Wiener’s diversity index (H’>3). Structure of that three forest types had an average density at 907 trees/ha with 80,89 m2 basal area value. Tree species with the highest frequency in the three habitat types were Anacardiaceae Campnosperma auriculatum (FHHM), Sapotaceae Madhuca laurifolia (FHG) and Ulmaceae Girroniera subequalis (FHDA). Hylobatidae habitat at Western Batang Toru Forest had a complete forest stratification level which were strata A, B, C and D. The highest space available on the gibbon and siamang habitat was strata C or 11-20 meter height above ground. Gibbon and siamang used mostly strata B and C at their habitat. It was related to the vegetation support for Hylobatidae movement and protection in their habitat, as well as food resources’s availability on those strata. Protection effort has to do to protect Western Batang Toru Forest ecosystem, because those forest region still get a threats and pressures from gold mining and logging area recently.
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Judul: Membran polistirena dengan ragam suhu perendaman untuk pervaporasi alkohol
Abstrak: Polystyrene membrane with PLURONIC as porogen, can be utilized in alcohol pervaporation. The polystyrene membrane was made by reverse phase method which was started with making of polymeric mixed solution between polystyrene and PLURONIC in dichloromethane with 2 different compositions, i.e.-polystyrene :PLURONIC:dichloromethane 17:0:83 and 17:1:82. The solution was stirred up for 5 hours with ultrasonic and casted on the glass plate surface, and then it was immersed into water at 40, 50, and 60 oC. The highest pervaporation result was 90,2% alcohol purities at 50 oC immersion temperature. However, this result was not good enough because the alcohol purities was lower than the standard alcohol purities at 91,6%.
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