Judul: Komposisi dan Distribusi Moluska di Dataran Karang (Reef-flat) Cagar Alam Leuweung Sancang Kabupaten Garut, Jawa Barat
Abstrak: Moluska merupakan salah satu komoditi di bidang perikanan yang potensial untuk dikembangkan, Di Indonesia, pemanfaatan dari jenis-jenis moluska ini belum mendapat perhatian yang sungguh-sungguh. Hal ini disebabkan masih kurangnya informasi tentang perikehidupan moluska dan teknologi untuk membudidayakannya/pengelolaannya. Penelitian terhadap komposisi dan distribusi moluska di dataran karang (reef-flat) Cagar Alam Leuweung Sancang, Kabupaten Garut , Jawa Barat, dilakukan mulai akhir April sampai dengan akhir Juni 1984.
Keyword: 

Judul: Struktur komunitas moluska pada habitat padang lamun, hutan mangrove dan batu karang di perairan Teluk Banten bagian barat, Jawa Barat
Abstrak: Tujuan penelitian ini adalah untuk mengetahui struktur komunitas moluska pada habitat padang lamun, hutan mangrove dan batu karang di perairan Teluk Banten Bagian Barat, dengan mengkaji (a) Struktur komunitas moluska, dengan melihat komposisi jenis, kepadatan, pola penyebaran, keanekaragaman, keseragaman dan dominansi, (b) Faktor-faktor lingkungan yang diketahui banyak berperan dalam kehidupan moluska meliputi kualitas air dan substrat. Penelitian dilaksanakan di perairan Teluk Banten Bagian Barat, Kabupaten Serang, Jawa Barat dimulai dari tanggal 4-25 Nopember 1995. Lokasi penelitian dibagi menjadi empat stasiun pengamatan (pengambilan contoh), yaitu Stasiun I di perairan Teluk Grenyang, Stasiun II di perairan Pantai Margagiri, Stasiun III di perairan sekitar Pulau Tarahan dan Stasiun IV di perairan Teluk Sekantung. Metode penelitian yang digunakan adalah metode transek garis. Pengukuran parameter fisika dan kimia meliputi pengukuran kualitas air (suhu, kecerahan, kedalaman, pH, salinitas, oksigen terlarut, amonia, nitrit dan ortofosfat) dan analisis substrat (tekstur, pH dan C-organik). Analisis data moluska dilakukan dengan menghitung kepadatan, pola penyebaran, keanekaragaman, keseragaman dan dominansi serta indeks kesamaan untuk melihat pengelompokan lokasi. ...
Keyword: 

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.
Keyword: