Judul: Peranan sistem biofilter dan kapur dalam proses reklamasi air bekas pakai pemeliharaan ikan mas (Cyprinus carpio Linn.)
Abstrak: Suatu penelitian telah dilakukan dari tanggal 12 Juni sampai dengan tanggal 28 September 1982 di Balai Penelitian Perikanan Darat Bogar, yang bertujuan untuk mengetahui peranan sistem biofilter dan kapur dalam proses reklamasi air bekas pakai pemeliharaan ikan Mas (Cyprinus aarpio Linn), serta mengevaluasi kualitas air yang dihasilan selama masa uji. Peranan Sistem biofilter dan Kapur dievaluasi dari efektivitas laju penurunan BOD5. Kualitas air dievaluasi berdasarkan parameter oksigen (02), Kebutuhan Oksigen Bio­ kimia (BOD) dan Ammonia (NH3). Parameter penunjangmeliputi Nitrit (N02), Nitrat (N03), pH, alkalinitas total dan kelimpahan bakteri pada media filter. Air uji yang digunakan diperoleh dari unit pemeliharaan ikan Mas sistem resirkulasi. Unit resirkulasi dilengkapi corong sedimentasi yang mengambil buangan organik bentuk padat. Kemudian padatan organik tersebut dihancurkan dan disimpan dengan air bekas pemeliharaan, dan selanjutnya dipergunakan sebagai air uji.
Keyword: Reclamation;, Cyprinus carpio;

Judul: Aplikasi Sistem Resirkualsi Air Terkendali (SRAT) pada budidaya ikan Mas (Cyprinus carpio)
Abstrak: Sektor perikanan merupakan salah satu sumber andalan dalam pembangunan Indonesia. Produksi dari perikanan budidaya sendiri secara keseluruhan meningkat dengan rata-rata 4,9% per tahun. Ikan mas (Cyprinus carpio) merupakan komoditas penting dalam budidaya perikanan air tawar. Pada kurun waktu 1992-1996, produksi ikan mas menduduki peringkat pertama dari total produksi nasional ikan air tawar hasil budidaya. Produksi ikan mas pada tahun 1997 sebesar 146.672 ton dan memberikan kontribusi sebesar 54,18% dari total produksi secara nasional. Petani biasanya membudidayakan ikan mas di kolam-kolam secara tradisional baik di kolam air tenang atau kolam air deras, mulai dari pemijahan, penetasan hingga pendederan/pembesaran. Permasalahan yang sering terjadi adalah ikan mengalami stress ketika terjadi perubahan kualitas air sehingga ikan mati dan mengakibatkan produktivitas ikan menurun. Hal ini bisa disebabkan oleh tingginya proses metabolisme ikan selama dibudidayakan akibat pengaruh dari kondisi alam seperti cuaca yang fluktuasi perubahanya sangat tinggi. Kualitas air yang buruk akan menurunkan tingkat kelangsungan hidup ikan. Oleh karena itu, diperlukan keadaan air dan lingkungan yang terjaga kualitasnya selama proses pembenihan. Salah satu cara untuk menjaga kualitas air yaitu dengan menggunakan sistem resirkulasi air terkendali (SRAT). Selain itu, keuntungan sistem ini adalah hemat air dan tidak memerlukan lahan yang luas. Tujuan penilitian ini adalah mengaplikasikan sistem resirkulasi air terkendali (SRAT) pada budidaya ikan mas untuk menjaga kualitas air yang meliputi, kandungan oksigen terlarut (DO), pH, EC/TDS, suhu dan kadar ammonia (NH3).
Keyword: 

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