Judul: Kelimpahan bakteri dalam budidaya cacing sutera limnodrilus sp. yang dipupuk kotoran ayam hasil fermentasi
Abstrak: Pemupukan dalam sistem budidaya cacing sutera bertujuan untuk meningkatkan pertumbuhan cacing. Pupuk tersebut menyumbang kandungan N organik yang diperlukan untuk pertumbuhan bakteri sebagai sumber makanan cacing. Penelitian ini bertujuan untuk mengetahui kelimpahan bakteri pada substrat media budidaya cacing sutera Limnodrilus sp. yang dipupuk dengan kotoran ayam hasil fermentasi pada dosis berbeda dan untuk mengetahui pengaruh kelimpahan bakteri terhadap pertumbuhan cacing sutera. Penelitian dilaksanakan di Kolam Percobaan Perikanan Babakan, Dramaga, Bogor dan di Laboratorium Kesehatan Ikan, Departemen Budidaya Perairan, Fakultas Perikanan dan Ilmu Kelautan, Institut Pertanian Bogor pada bulan Maret sampai Mei 2005. Wadah penelitian berupa kotak kayu yang dilapisi plastik hitam dengan ukuran 100x 20x15 cm. Cacing diperoleh dari pengumpul di Leuwikopo, Bogor dengan penebaran awal adalah 150 individu/wadah. Media pemeliharaan berupa campuran kotoran ayam dan lumpur halus dengan perbandingan 1:1. Pengelolaan air dengan mengalirkan air pada debit 0,6 liter/menit/wadah. Pupuk yang digunakan adalah kotoran ayam yang difermentasikan dengan aktivator EM Rancangan perlakuan yang digunakan adalah rancangan acak lengkap dengan 3 perlakuan dan 3 kali ulangan. Pemberian pupuk kotoran ayam hasil fermentasi pada perlakuan 1 sebesar 0,65 kg/m² (130 gr/wadah), perlakuan 2 sebesar 0,8 kg/m² (160 gr/wadah), perlakuan 3 sebesar 0,95 kg/m² (190 gr/wadah). Pemupukan dilakukan setiap dua hari sekali. Kelimpahan bakteri pada 10 hari pertama masa pemeliharaan cacing mencapai 10 CFU/ml dan terus menurun menjadi 10-10 CFU/ml pada akhir penelitian (hari ke-60). Tingginya kelimpahan bakteri pada awal penelitian diikuti peningkatan laju pertumbuhan cacing sutera sehingga tercapai populasi dan biomassa tertinggi pada hari ke-20 masing-masing sebesar 5.151-11.948 ind/m² dan 6,316-14,649 gr/m². Kemudian pada hari selanjutnya laju pertumbuhan menurun sampai akhir penelitian. Perbedaan dosis pemupukan tidak memberikan pengaruh yang nyata (P>0,05) terhadap kelimpahan bakteri dan pertumbuhan. cacing. Hasil analisa beberapa parameter kualitas air selama pemeliharaan cacing termasuk layak bagi kehidupan cacing yaitu DO (1,99-6,73 ppm), pH (5,44-7,48), amonia (< 0,001-0,01207 ppm) dan suhu (27-28 °C).
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Judul: Pengaruh Pemupukan Harian Kotoran Ayam Terhadap Pertumbuhan Populasi Dan Biomassa Limnodrillus
Abstrak: Penelitian ini bertujuan untuk mengetahui pengaruh pemupukan harian dengan kotoran ayam kering terhadap populasi dan biomassa cacing sutera (Limnodrillus). Penelitian dilaksanakan di Kolam Percobaan Perikanan Babakan, IPB, Darmaga, Bogor pada bulan Maret sampai April 2004. Wadah yang digunakan berupa kotak kayu dengan ukuran 80 x 20 x15 cm. Kotak kayu dilapisi plastik untuk menghindari kebocoran. Cacing uji yang digunakan adalah cacing sutera yang diperoleh dari pengumpul cacing sutera dengan densitas cacing adalah 150 individu / wadah. Media pemeliharaan berupa campuran antara lumpur halus dan kotoran ayam. Pengelolaan air dilakukan dengan pengaliran air sebesar 500 ml/menit atau 3,13 l/menit untuk setiap m2 wadah yang dipakai.
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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