Judul: Potensi Bakteri Rhizosfer sebagai Pupuk Hayati pada Persemaian Tanaman Sengon (Paraserianthes falcataria).
Abstrak: Biological fertilizer is one of alternative fertilizer from nitrogen fixing bacteria for albizia. The aim of this research was to utilize rhizosfer bacteria from forest soil as biological fertilizer for albizia nursery (Paraserianthes falcataria). Growing media for albizia seedling was polybag filled of acid soil from Jasinga (Ultisol type) with pH 4.7 and peat with ratio 2:1. Rhizosfer bacteria used in the study was Burkholderia cepacia with isolate codes L6.5 and L10.1. Streak quadrant results showed rhizosfer bacteria had coccus form, was not absorb pink color, and had convex elevation. Rhizosfer bacteria isolate L6.5 and L10.1 that were added with ½ N from NPK fertilizer for albizia nursery showed similar influence with fertilization using NPK dosage as recommended. NPK fertilizer with ½ N dosage that was added to rhizosfer bacteria showed influences at root length, lateral root amount, crown length, wet weight, dry weight, and nodule amount compared with control.
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Judul: Penggunaan Rhizobium dan bakteri pelarut fosfat pada tanah mineral masam untuk memperbaiki pertumbuhan bibit sengon (Paraserianthes falcataria (L.) Nielsen)
Abstrak: The main problem of acid soil is the availability of nutrients and high exchangeable A1 content. Soil acidity will reduce many legum plant growth, decrease number of rhizobia and nodule initiation and inhibit the function and growth of ndule. Based on these problems, the experiment was cmducted to obtain the acid and A1 tolerant strain of Rhizobium isolated from sengon nodules, and to obtain the effective strain of Rhizobium in fixing atmospheric nitrogen, and phosphate solubilizing bacteria in increasing P availability, thus support plant growth. The study was focused on three aspects: ( I ) Research on Rhizobim consist of (a) collection of Ahitobiurn strains from sengon nodules, (b) screening Rhizobium toward acidity and high concentration of Al, (c) screening Rhizobium based on their ability to fix nitrogen, (d) marking the selected Rhizobim with antibiotic, and screening the resistant mutants, (e) assesing the effectiveness of the selected Rhizobim on acid soil in greenhouse; (2) Research on phosphate solubilizing bacteria, consist of (a) isolation of phosphate solubilizing bacteria, (b) selection of phosphate solubilizing bacteria in dissolving P from rock phosphate and Alms in liquid medium and acid soil, (c) identification of selected phosphate solubilizing bacteria, (d) determination of organic acid produced by selective phosphate solubilizing bacteria, (e) assessing the effectiveness of selected phosphate solubilizing bacteria in greenhouse; (3) winmulation between Rhizobim and phosphate solubilizing bactetia in greenhouse and field experiments., Permasalahan yang utama dari tanah masam adalah cadangan unsur hara kesuburan tanah yang rendah, kandungan Al dapat ditukar tinggi, dan mempunyai kapasitas retensi P yang tinggi. Kemasaman tanah pada tanaman leguminosa akan menyebabkan terganggunya pertumbuhan tanaman, jumlah rhizobia dan pembentukan bintil akar berkurang serta terhambatnya fungsi dan perkembangan bintil.
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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