Judul: Efisiensi Operasional Pemberian Pakan pada Budidaya Penggemukan Kepiting Bakau Scylla serrata dalam Sistem Apartemen RAS
Abstrak: Kepiting bakau (Scylla serrata) merupakan komoditas akuakultur yang memiliki nilai ekonomis tinggi di pasar internasional. Operasional pemberian pakan pada budidaya kepiting bakau sistem RAS tidak efisien. Efisiensi dalam operasional pemberian pakan pada budidaya kepiting bakau perlu ditingkatkan agar dapat memberikan penghematan waktu tenaga kerja dan mengurangi biaya operasional pemberian pakan. Penelitian ini bertujuan menganalisis efisiensi operasional pemberian pakan satu, dua, dan tiga kali sehari dengan mengukur kinerja produksi dan analisis usaha pada budidaya kepiting bakau Scylla serrata pada sistem apartemen RAS. Rancangan Acak Lengkap digunakan dalam penelitian ini, terdiri dari tiga perlakuan frekuensi pemberian pakan, yaitu satu, dua, dan tiga kali sehari dengan masing-masing tiga ulangan. Pemberian pakan satu, dua, dan tiga kali sehari tidak berpengaruh signifikan terhadap tingkat kelangsungan hidup, pertumbuhan bobot mutlak, pertumbuhan panjang dan lebar karapas, waktu dan jumlah molting, persentase molting, jumlah konsumsi pakan, rasio konversi pakan, dan efisiensi pemanfaatan pakan. Pemberian pakan dua kali sehari menghasilkan efisiensi tenaga kerja sebesar 1,08% dan memperoleh keuntungan paling besar yaitu Rp5.342.008.
Keyword: analisis usaha, kelangsungan hidup, pertumbuhan, tenaga kerja, biaya operasional

Judul: Padat Tebar Optimal pada Peningkatan Produksi Kepiting Bakau Scylla serrata dalam Sistem Resirkulasi
Abstrak: Kepiting bakau Scylla serrata merupakan produk perikanan unggulan yang memiliki nilai ekonomis tinggi dan potensial untuk dikembangkan. Efisiensi lahan dan media pemeliharaan perlu dilakukan untuk meningkatkan kuantitas dan kualitas produksi kepiting bakau. Penelitian ini bertujuan untuk menentukan padat tebar optimal pada budidaya kepiting bakau Scylla serrata dalam sistem resirkulasi. Kepiting bakau dengan bobot rata-rata 150±0.6 g dipelihara dalam kontainer plastik berukuran 60×40×40 cm selama 60 hari dengan pemberian pakan secara at satiation sebanyak dua kali sehari. Penelitian dilakukan dengan 3 perlakuan dan 3 ulangan yaitu padat tebar 5, 10, dan 15 ekor setiap wadah pemeliharaan. Hasil penelitian menunjukkan bahwa kinerja pertumbuhan kepiting bakau terbaik terdapat pada perlakuan 10 ekor setiap wadah pemeliharaan dengan tingkat kelangsungan hidup 73.33±5.77%, biomassa sebesar 1380.10 g, laju pertumbuhan mutlak sebesar 0.68±0.01 g/ekor/hari, efisiensi pakan sebesar 9.89±0.11%, dan nilai rasio konversi pakan sebesar 10.11±0.11.
Keyword: biomassa, kepiting bakau, laju pertumbuhan, rasio konversi pakan, tingkat kelangsungan hidup

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