Judul: Evaluasi Kinerja Pendederan Ikan Lele Clarias sp. Ukuran 5 cm di dalam Sistem Resirkulasi pada Padat Penebaran dan Sumber Benih yang Berbeda
Abstrak: Penelitian ini bertujuan untuk mendapatkan produktivitas yang optimal pada produksi pendederan lele ukuran 5 cm. Perlakuan penelitian ini adalah sumber benih yang berbeda yaitu benih produksi sendiri dan benih dari luar dengan padat penebaran 2000, 2500, dan 3000 ekor/m3 dengan sistem resirkulasi. Penelitian ini meliputi persiapan sistem resirkulasi, penebaran ikan, pemberian pakan, dan pencegahan penyakit. Ikan yang digunakan adalah benih lele dengan panjang ratarata 5,32±0,17 cm dan bobot rata-rata 1,41±0,10 gram. Pengamatan dilakukan selama 21 hari dengan mengukur bobot dan panjang ikan setiap minggu. Jika terdapat ikan yang mati akan diangkat dan dihitung jumlahnya untuk mengetahui pertumbuhan dan tingkat kelangsungan hidup. Hasil penelitian menunjukkan padat penebaran 3000 ekor/m3 dengan benih hasil produksi sendiri merupakan padat penebaran yang optimal yang menghasilkan produktivitas tertinggi dengan derajat kelangsungan hidup (KH) sebesar 77,63%; laju pertumbuhan harian (LPH) sebesar 11.09 %, dan efisiensi pakan sebesar 119.37 %.
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Judul: Pengaruh Padat Penebaran Dengan Ukuran Yang Berbeda Pada Sistem Pendederan Terhadap Kinerja Pertumbuhan Benih Ikan Lele Clarias
Abstrak: Penelitian ini bertujuan untuk mengevaluasi pemeliharaan ikan lele pada pendederan I dengan kepadatan dan ukuran tebar berbeda terhadap pertumbuhan dan efisiensi pakan. Benih ikan lele umur 10 hari dikelompokkan terlebih dahulu menjadi dua ukuran berbeda M (1,6-1,9 cm) dan S (1,4-1,5 cm). Benih tersebut dipelihara dalam bak terpal ukuran 6x3x0,5 meter dengan ketinggian media hingga 40 cm. Ikan dipelihara selama 13 hari dengan padat tebar 1000 e/m2 dan 2000 e/m2 dengan dua ukuran tebar bebeda. Pemberian pakan dilakukan secara at satiation. Jenis pakan yang diberikan yaitu fengli dan PF 500. Pakan diberikan pada pukul 06.00, 16.00 dan 22.00 WIB. Hasil penelitian menunjukkan bahwa ikan yang ditebar dengan ukuran M (besar) dengan kepadatan 1000 e/m2 memiliki pertumbuhan dan efisiensi pakan yang lebih baik yang dicirikan dengan komposisi ukuran panen mayoritas ukuran L (67,6 %) di akhir masa pemeliharaan.
Keyword: ikan lele, kepadatan, ukuran tebar, pertumbuhan, efisiensi pakan

Judul: Characteristic of Overshooting Top (OT) Based on  Himawari  8  Satellite  as  a  Convective  Cloud  Feature  that  Generates  Extreme Weather in the Java Island Region
Abstrak: Overshooting Top (OT) is a feature at the top of a convective cloud that is associated with extreme weather. Research on OT in tropical Indonesia is still very limited. The existence of geostationary satellites with wide area coverage and fast frequency observations is useful for observing the fast dynamics of the OT life cycle. Therefore, this study intends to analyze the relationship between OT and extreme weather, updraft and thermodynamic conditions of OT when extreme weather occurs, the best objective method for detecting OT in the day time and night time, and the spatiotemporal distribution of OT in the tropical region of Java Island during the 2018-2021 period. Based on visual analysis using visible channel and Himawari 8 sandwich products, 87% of extreme weather events in Java were accompanied by the appearance of OT. It indicates that the presence of the OT pattern is a convection cloud pattern or feature that is closely related to extreme weather events for the Java Island region. The existence of a time lag between the appearance of OT and extreme weather events on Java Island indicates that the OT of convection cloud can be used as a precursor or nowcasting for the appearance of extreme weather. Most of the convective cloud OT features during extreme weather events on Java Island have altitude that were only able to exceed the altitude of the equilibrium level and few were able to exceed the tropopause level of 9 km – 16 km. The difference in atmospheric conditions during extreme weather events on Java Island, which is in the tropics and subtropics, is a strong and unstable convective energy condition characterized by a larger CAPE, as well as unstable KI, LI, SI and TTI values. It is offset by kinematic factors in the form of a weak vertical wind shear (bulk wind shear 0-6 km) and a higher freezing point height. The difference between extreme weather events in the Java Island region and other tropical regions compared to subtropical regions is the strong updraft speed of convection clouds. The IRW Texture COMB algorithm based on the IRW-Texture Gradient modification and the COMB algorithm shows a significant increase in quality for detecting OT and non-OT pixels in Java. Rainy days with rainfall > 50 mm/day are very common in areas with an altitude of > 500 m. On the other hand, the level of convection activity which is indicated by the presence of OT and lightning is significantly reduced in this area. OT of convective clouds appear more frequently during the DJF season and less frequently during the JJA season. OT often appears during the day time and rarely at night time. Most OTs appear in the central part, away from the south and north coasts of Java Island during the day, while OTs that appear near the south and north coasts of Java Island can appear in the morning or afternoon.
Keyword: convective clouds, extreme weather, Overshooting Tops, Himawari 8 Satellite