Judul: Improvement Contribution and Efficiency Estimation in Application of "Precipalm" Fertilizer Dosage Recommendation at PT Kalimantan Agro Nusantara, East Kutai, East Kalimantan
Abstrak: Asesmen lapangan dilaksanakan di PT Kalimantan Agro Nusantara, Kebun Nusantara, Kutai Timur, Kalimantan Timur pada bulan Januari 2020 sampai April 2020. Kegiatan studi bertujuan mengestimasi neraca nitrogen untuk mengetahui jejak nitrogen dan efisiensi penerapan dosis pemupukan nitrogen Precipalm pada perkebunan kelapa sawit. Estimasi neraca nitrogen di PT KAN Kebun Nusantara kondisi pra pemupukan diperoleh -85.67 kg N ha-1 tahun-1, sedangkan untuk kondisi pasca pemupukan diperoleh untuk kedua perlakuan dosis pemupukan baik PPKS dan Precipalm sebesar 23.56 kg N ha-1 tahun-1 dan 25.24 kg N ha-1 tahun-1. Defisit N terjadi pada kondisi pra pemupukan jika tidak mempertimbangkan input sumber dan proses dekomposisi alami akibat dari tidak adanya pemupukan selama dua tahun terakhir, sedangkan pada kondisi pasca pemupukan terjadi surplus N untuk kedua perlakuan. Jejak nitrogen produksi diperoleh untuk pra pemupukan sebesar 1.45 kg N ton TBS-1 serta untuk pasca pemupukan perlakuan PPKS dan Precipalm sama besar yaitu 3.19 kg N ton TBS-1 3.22 kg N ton TBS-1. Data jejak nitrogen produksi menunjukkan bahwa dinilai pada parameter jejak nitrogen keadaan tidak dipupuk lebih ramah lingkungan dibandingkan dengan keadaan setelah dipupuk. Estimasi efisiensi nitrogen untuk perlakuan dosis PPKS dan Precipalm diperoleh masing-masing sebesar 69.98% dan 70.09% untuk efisiensi input eksternal dan 89.53% dan 88.80% jika mempertimbangkan input internal, yang mana nilai tersebut tidak berbeda nyata., The study was carried out at PT Kalimantan Agro Nusantara, Kebun Nusantara, East Kutai, East Borneo from January 2020 to April 2020. The purpose of the study was to estimating the nitrogen balance to find out the nitrogen footprint and the application efficiency estimation of Precipalm nitrogen fertilizer application in oil palm plantations. Estimation of nitrogen balance at PT KAN Kebun Nusantara in pre-fertilization conditions was obtained -85.67 kg N ha-1 year-1, while for post-fertilization conditions obtained for the two treatments, both PPKS and Precipalm fertilization doses were 23.56 kg N ha-1 year-1 and 25.24 kg N ha-1 tahun-1. The N deficit occurs in the pre-fertilization condition if it does not consider the source input and natural decomposition process due to the absence of fertilization for the last two years, while in the post-fertilization condition there is a surplus of N for both treatments. Production nitrogen footprint obtained for pre-fertilization were 1.45 kg N ton TBS-1 and for post fertilization treatment PPKS and Precipalm were 3.19 kg N tons TBS-1 and 3.22 kg N tons TBS-1. Production nitrogen footprint data show that assessed on the nitrogen footprint parameter the unfertilized condition is more environmentally friendly than the post-fertilization condition. Estimation of nitrogen efficiency for PPKS and Precipalm dosage treatment were 69.98% and 70.09% for external input efficiency and 89.53% and 88.80%, respectively, when considering internal input, where these values were not significantly different.
Keyword: Precipalm, Neraca Nitrogen, Jejak Nitrogen, Efisiensi Pemupukan

Judul: Pengaruh Pupuk NPK Majemuk terhadap Peningkatan Produksi Tandan Buah Segar Kelapa Sawit (Elaeis guineensis Jacq.).
Abstrak: Kelapa sawit merupakan tanaman perkebunan yang memiliki peran penting bagi subsektor perkebunan dan penghasil minyak nabati. Salah satu faktor penting dalam produksi kelapa sawit adalah pemupukan. Kegiatan penelitian ini bertujuan mempelajari pengaruh aplikasi pupuk NPK majemuk terhadap pertumbuhan dan produksi tandan buah segar kelapa sawit. Penelitian dilakukan pada Januari 2023 hingga Maret 2024. Penelitian dilaksanakan di Blok 1 Kebun Pendidikan dan Penelitian Kelapa Sawit IPB-Cargill Kecamatan Jonggol, Kabupaten Bogor. Analisis tanah serta analisis daun dilakukan di Laboratorium Pengujian Departemen Agronomi dan Hortikultura Fakultas Pertanian. Perlakuan disusun dalam 6 taraf pemupukan yaitu: (1) kontrol tanpa aplikasi pupuk (P0), (2) dosis standar sebagai pembanding (P1), (3) 0,5 dosis pupuk NPK 12 12-17 + 2 Mg (P2), (4) 1 dosis pupuk NPK 12-12-17 + 2 Mg (P3), (5) 1,5 dosis pupuk NPK 12-12-17 + 2 Mg (P4), (6) 2 dosis pupuk NPK 12-12-17 + 2 Mg (P5). Data yang diperoleh dianalisis ragam pada taraf α = 0,05 dan dilanjutkan dengan uji DMRT. Perlakuan 1 dosis pupuk NPK majemuk 12-12-17 + 2 Mg dosis yaitu 6,75 kg tanaman-1 tahun-1 menghasilkan bobot tandan buah segar (TBS) 43% lebih baik dibandingkan kontrol, jumlah tandan buah segar (TBS) 2% lebih baik dibandingkan kontrol, dan bobot janjang rata-rata (BJR) 36% lebih baik dibandingkan kontrol. Produktivitas tanaman kelapa sawit pada perlakuan yang diberi perlakuan 1 dosis pupuk NPK majemuk 12-12-17 + 2 Mg dosis yaitu 6,75 kg tanaman-1 tahun-1 menghasilkan produktivitas tertinggi jika dibandingkan dengan kontrol dan perlakuan lainnya yaitu sebesar 36,87 ton ha-1 tahun-1., Oil palm is a plantation crop that has an important role for the plantation subsector and vegetable oil producers. One of the important factors in oil palm production is fertilization. This research activity aims to identify the effect of compound NPK fertilizer application on the growth and production of oil palm fresh fruit bunches. The research was conducted from January 2023 to March 2024. The research was conducted in Block 1 of the IPB-Cargill Oil Palm Education and Research Farm, Jonggol District, Bogor Regency. Soil analysis and leaf analysis were conducted at the Testing Laboratory of the Department of Agronomy and Horticulture, Faculty of Agriculture. Treatments were arranged in 6 fertilizer levels, namely: (1) no fertilizer application (P0), (2) standard NPK fertilizer as a comparison (P1), (3) 0,5 dose of NPK 12-12-17 fertilizer + 2 Mg (P2), (4) 1 dose of NPK 12-12-17 + 2 Mg (P3), (5) 1.5 dose of NPK 12-12-17 + 2 Mg (P4), (6) 2 dose of NPK 12-12-17 + 2 Mg (P5). The data obtained were analyzed for variance at the α = 0,05 level and continued with the DMRT test. The treatment of 1 dose of compound NPK fertilizer 12-12-17 + 2 Mg dose at 6.75 kg plant-1 year-1 produced 43% better fresh fruit bunch (FFB) weight than the control, the number of fresh fruit bunches (FFB) was 2% better than the control, and the average basket weight (BJR) was 36% better than the control. Productivity of oil palm plants in the treatment given 1 dose of compound NPK fertilizer 12-12-17 + 2 Mg at 6.75 kg ha-1 year-1 produced
Keyword: pemupukan, NPK majemuk, produktivitas, tandan buah segar, fertilization, fresh fruit bunch, NPK compound, productivity

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology