Judul: Peningkatan Kelarutan P dari Sumber Fosfat Sukar Larut dengan Menggunakan Bakteri Pelarut P
Abstrak: Penelitian ini bertujuan untuk mengetahui sejauh mana bakteri pelarut P yang diisolasi dari tanah berkemampuan meningkatkan kelarutan P pada : medium Pikovskaya yang mengandung fosfat sukar larut (trikalsium fosfat dan batuan fosfat), tanah masam (Andosol Sukamantri dan Podzolik Jasinga), dan tanah alkalin (Rendzina G. Masigit).
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Judul: Upaya Meningkatkan Kelarutan Fosfat Alam Melalui Kalsinasi dan Penggunaan Mikrob Pelarut Fosfat
Abstrak: Ketersediaan fosfat didalam tanah dapat ditingkatkan dengan memberikan fosfat alam (FA) ke dalam tanah. Salah satu upaya meningkatkan kelarutan FA diantaranya dilakukan menggunakan kalsinasi dan menambahkan mikrob pelarut fosfat. Mikrob pelarut fosfat (MPF) adalah mikrob yang memiliki kemampuan melarutkan fosfat yang tidak tersedia menjadi tersedia bagi tanaman. Penelitian ini bertujuan untuk menguji pengaruh kalsinasi FA dan penggunaan MPF dalam meningkatkan kelarutan P fosfat alam, serta dampaknya terhadap produksi dan serapan P tanaman. Penelitian dilaksanakan di Laboratorium Bioteknologi dan Lingkungan Departemen Ilmu Tanah dan Sumberdaya Lahan, Institut Pertanian Bogor. Kemampuan MPF ditetapkan dengan uji kualitatif dan kuantitatif menggunakan sumber fosfat sukar larut berupa fosfat alam. Hasil penelitian menunjukkan bahwa indeks pelarutan pada uji kualitatif berada pada kisaran 1.40-2.86 untuk bakteri SS19.7 dan kisaran 1.08-1.13 untuk fungi FPF 4. Hasil uji kuantitatif menunjukkan kemampuan MPF tergantung pada sumber fosfat sukar larutnya. Isolat bakteri SS19.7 dan fungi FPF 4 memiliki kemampuan melarutkan fosfat paling tinggi pada FA Rembang tanpa kalsinasi dibandingkan sumber fosfat sukar larut lainnya. Perlakuan yang diberikanpada aplikasi tanaman berupa penambahan sumber fosfat sukar larut, inokulasi MPF, dan kombinasi sumber fosfat sukar larut dengan isolat MPF. Hasil penelitian menunjukkan bahwa kombinasi perlakuan fosfat alam Rembang baik kalsinasi dan tanpa kalsinasi yang diberi fungi FPF 4 lebih tinggi meningkatkan bobot kering tanaman dan serapan P tanaman jagung manis dibandingkan perlakuan fosfat alam Mesir kalsinasi dan tanpa kalsinasi yang diberi MPF, serta mampu menyamai perlakuan pupuk SP-36 yang dikombinasikan dengan MPF
Keyword: fosfat sukar larut, inokulasi MPF, serapan P

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