Judul: Pengaruh Pemupukan Nitrogen terhadap Efektivitas Salvinis nolesta D. S. Mitchell dalam Menekan Gulma pada Tanaman Padi Sawah
Abstrak: Penelitian ini bertujuan untuk megetahui efektivitas S. molesta dalam menekan gulma, dan pengaruhnya terhadap pertumbuhan dan hasil padi sawah pada berbagi taraf pemupukan nitrogen. Rancangan yang digunakan adalah faktorial kelompok 3x3 dengan tiga ulangan. Dua faktor perlakuan yang digunakan adalah cara pengendalian gulma terdiri dari tanpa disiang, penyiangan biasa dan pemberian S. molesta. Tiga taraf pemupukan nnitrogen yang digunakan masing-masing 45, 90 dan 135 kg N/ha.
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Judul: Pemanfaatan Salvinia molesta D. S. Mitchell Untuk Menekan Pertumbuhan Gulma Pada Tanaman Padi Sawah
Abstrak: Tujuan percobaan ini adalah untuk mengetahui pengaruh Salvinia molesta yang dikaitkan dengan prosentase penutupan awal dan saat pemberian terhadap pertumbuhan gulma, pertumbuhan padi, komponen produksi dan produksi padi. Rancangan yang digunakan adalah Rancangan Acak Kelompok dengan tiga ulangan. Perlakuan yang diuji adalah petakan tanpa disiang dan tanpa diberi Salvinia molesta (Po), diberi Salvinia molesta dengan tingkat penutupan awal 10% diberikan pada 4 HST (P₁₁), tingkat penutupan awal 10% diberikan pada 14 HST (P1S2), tingkat penutupan awal 25% diberikan pada 4 HST (P₂S₁), tingkat penutupan awal 25% diberikan pada 14 HST (P252), tingkat penutupan awal 40% diberikan pada 4 HST (P351), tingkat penutupan awal 40% diberikan pada 14 HST (P352), tingkat penutupan awal 55% diberikan pada 4 HST (P451), tingkat penutupan awal 55% diberikan pada 14 HST (P4S2), tanpa Salvinia molesta dan disiang dua kali pada 21 HST dan 42 HST. Padi yang digunakan adalah varietas IR 36. Pemberian Salvinia molesta pada petak tanaman padi sawah dapat menekan pertumbuhan gulma total, gulma golongan berdaun lebar dan gulma golongan teki. Dari delapan spesies gulma dominan yang ditentukan, hanya Cyperus difformis yang dapat dipengaruhi pertumbuhannya oleh Salvinia molesta...
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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