Judul: Studi lignifikasi sebagai salah satu tolok ukur viabilitas benih
Abstrak: Studi lignifikasi sebagai tolok ukur viabilitas benih Pinus merkusii dilaksanakan di laboratorium Ilmu dan Teknologi Benih, laboratorium Terpadu Analis Kimia IPB, dan laboratorium Titrimetri SMAKBO mulai bulan April sampai dengan Mei 1993. Penelitian ini bertujuan untuk mempelajari pembentukan lignin kecambah sebagai tolok ukur viabilitas benih. Penelitian ini disusun secara faktorial dengan menggunakan rancangan acak lengkap. Penelitian terdiri dari dua faktor yaitu tingkat viabilitas benih dengan tiga taraf terdiri dari viabilitas rendah (V1), viabilitas sedang (V2) dan viabilitas tinggi (V3). Faktor kedua tingkat tekanan osmotik dengan tiga taraf terdiri dari 0 bar (P1), -1.0 bar (P2), -2.5 bar (P3). Setiap perlakuan dilaksanakan dengan tiga ulangan. Pengamatan dilakukan terhadap viabilitas benih dengan tolok ukur Persentase Kecambah Normal, Bobot Kering Kecambah, Kecepatan Tumbuh, Kese- rempakan Tumbuh, dan Kandungan Lignin Kecambah. Hasil penelitian menunjukkan bahwa terdapat interaksi yang nyata antara perlakuan tingkat viabilitas dan tingkat tekanan osmotik pada semua peubah yang diamati kecuali Persentase Kecambah Normal. Sedangkan faktor tunggal berpengaruh sangat nyata pada semua tolok ukur. ...
Keyword: 

Judul: Studi kandungan lignin untuk uji vigor pada benih pinus (Pinus merkusii Jung et de Vriese
Abstrak: Penelitian ini bertujuan untuk mempelajari kandungan lignin hipokotil kecambah untuk uji vigor pada benih pinus dan kemungkinannya sebagai tolok ukur vigor benih secara cepat dan tepat. Penelitian lapang dilakukan di rumah kaca Balai Teknologi Perbenihan Kehutanan, Ciheuleut, Bogor dan analisis lignin dilakukan di laboratorium PAU TPG Darmaga. Penelitian ini berlangsung dari Bulan November 1995 sampai Bulan Mei 1996. Penelitian disusun secara faktorial menggunakan rancangan acak kelompok yang terdiri dari dua faktor yaitu tingkat vigor benih dan media tumbuh. Tingkat vigor benih terdiri dari tiga taraf yaitu tinggi, sedang, dan rendah. Media tumbuh terdiri dari empat taraf yaitu komposisi campuran tanah, pasir dan kompos dengan perbandingan 7:2:1 (M1), 0:10:0 (M2), 9:1:0 (M3) dan 10:0:0 (M4). Tolok ukur yang diamati adalah daya berkecambah, bobot kering kecambah, keserempakan tumbuh, kecepatan tumbuh, kandungan lignin hipokotil kecambah 10 dan 14 hari setelah taman (HST), tinggi bibit 15, 30, 45, dan 60 hari setelah tanam (HST).
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