Judul: Inventarisasi Serangga Perusak Rotan Manau (Calamus manan Miq.) di BKPH Jasinga KPH Bogor
Abstrak: Sekitar pemasok 85% dari seluruh rotan yang beredar di pasaran dunia, Indonesia selama ini masih mengandalkan produksinya dari hutan alam. Salah satu jenis rotan komersial dari hutan alam. Salah satu jenis rotan komersial yaitu rotan manau (Calamus manan Miq.), merupakan jenis rotan yang bernilai ekonomis tinggi dan banyak diminati leh konsumen (Alrasjid, 1980; Hamzah, 1980).
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Judul: Evaluasi uji provenansi rotan manau (Calamus manau) di Haurbentes, Jasinga, KPH Bogor
Abstrak: Indonesia sebagai negara pengekspor utama rotan ke pasaran internasional, perlu berusaha mempertahankan dan meningkatkan peranannya sebagai produsen utama rotan dengan rotan tanaman hasil budidaya. Usaha budidaya dilakukan karena semakin berkurangnya sumberdaya rotan di hutan alam. Uji provenansi rotan manau dilaksanakan untuk menunjang budidaya rotan manau demi keberhasilan penanamannya, karena menurut Soerianegara dan Djamhuri (1979) penanaman pohon hutan tanpa mengetahui asal benih adalah tidak dibenarkan. Tujuan penelitian adalah untuk menilai pertumbuhan dan variasi genetik 6 (enam) provenans rotan manau (Calamus manan) pada umur tiga tahun. Penelitian dilaksanakan di kebun percobaan Haurbentes, Jasinga, KPH Bogor yang dikelola Pusat Penelitian dan Pengembangan Hutan Bogor Pengukuran dan pengamatan di laksanakan pada bulan Oktober 1994. Data yang dikumpulkan meliputi panjang rotan manau yang diukur dari permukaan tanah sampai titik tumbuh rotan manau (taxis) dengan mengikuti bentuk batangnya, diameter rotan manau pada pangkal batang, jumlah daun dari pangkal sampai daun terakhir di ujung batang dan anak daun pada lima daun terakhir serta pengamatan terhadap morfologi daun dan struktur duri. Data yang diperoleh dianalisis dengan menggunakan Rancangan Acak Berblok (Steel dan Torrie, 1989) sesuai rancangan percobaan yang ada dengan 6 perlakuan dan 3 blok (18 petak coba). Tiap petak coba terdiri atas 25 batang tanaman...
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Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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