Judul: Weeds and Weed Seed Bank as Components of Agrobiodiversity in Palm Oil Plantations
Abstrak: Gulma dan weed seed bank merupakan komponen penting dari keanekaragaman hayati dalam agroekosistem perkebunan kelapa sawit. Tujuan dari penelitian ini adalah mempelajari komposisi, distribusi, dan dinamika gulma serta seed bank gulma dalam tanah di perkebunan kelapa sawit. Penelitian dilakukan pada bulan November 2023 hingga Februari 2024 di Perkebunan Kelapa Sawit Bangun Bandar PT. Socfindo, Medan, Sumatera Utara. Penelitian dilakukan dengan menggunakan metode observasi dengan meninjau langsung keberadaan gulma di lapangan. Penentuan lokasi penelitian dilakukan secara purposive berdasarkan berbagai tahun tanam yang berbeda. Teknik pengambilan sampel dilakukan dengan sistem simpel random sampling dengan metode kuadrat berdasarkan kriteria kedalaman tanah dan tahun tanam kelapa sawit. Faktor pertama adalah tahun tanam kelapa sawit yaitu kelapa sawit dengan tahun tanam 2022, tahun tanam 2019, tahun tanam 2012, dan tahun tanam 2004 sedangkan faktor kedua adalah kedalaman tanah yang terdiri dari kedalaman tanah 0-10 cm, kedalaman tanah 10-20 cm, dan kedalaman tanah 20-30 cm. Faktor lingkungan seperti suhu, kelembapan udara, dan intensitas cahaya di bawah tegakan kelapa sawit berpengaruh pada jenis gulma yang dominan tumbuh. Komposisi gulma juga bervariasi berdasarkan tahun tanam, dengan rerumputan mendominasi pada tanaman muda dan daun lebar pada tanaman yang lebih tua. Analisis koefisien komunitas menunjukkan perubahan dalam homogenitas komunitas gulma seiring dengan pertambahan tahun tanam, mungkin terkait dengan pengaruh lingkungan dan praktik pertanian. Potensi soil seed bank gulma tertinggi terdapat pada kedalaman tanah 0-10 cm, dengan spesies seperti Cynodon dactylon dan Selaginella willdenowii mendominasi. Keanekaragaman gulma dalam soil seed bank bervariasi berdasarkan kedalaman tanah dan tahun tanam, menunjukkan pola dominasi yang bervariasi. Absennya beberapa spesies gulma di soil seed bank mengindikasikan potensi kehilangan biodiversitas terkait pentingnya perlindungan habitat alami dan pengelolaan gulma yang berkelanjutan untuk mempertahankan biodiversitas dalam ekosistem kelapa sawit., Weed and weed seed banks are crucial components in the agroecosystem biodiversity of oil palm plantations. This research was to study the composition, distribution, and dynamics of weeds, as well as the potency of the soil weed seed bank in oil palm plantations. The research was conducted between November 2023 and February 2024 at Bangun Bandar Oil Palm Plantation PT. Socfindo in Medan, using the observation method by directly reviewing the presence of weeds in the field. Determination of the research location was carried out purposively based on a variety of different planting years. The sampling technique was carried out with a simple random sampling system with the quadrat method based on the criteria of soil depth and oil palm planting year. The first factor is the year of oil palm planting (namely oil palm with planting year 2022, 2019, 2012, and 2004) while the second factor is three soil depths (0-10 cm, 10-20 cm, and 20-30 cm). Temperature, humidity, and light intensity around the oil palm canopy significantly impact the dominance of weed species. The study found that the composition of weeds varies depending on the age of the plants, with grasses being more prevalent in younger and broad-leaved weeds in older plants. The examination of weed community homogeneity using the community coefficient showed changes with increasing crop years, potentially due to environmental impacts and agricultural practices. The greatest potential
Keyword: Agroecosystem management, Biodiversity dynamics, Seed ecology, Vegetation diversity

Judul: Weed Management of Oil Palm (Elaeis guineensis Jacq.) in Surya Adi Estate, PT Binasawit Makmur, South Sumatra
Abstrak: The productivity of Indonesian palm oil has not reached its maximum potential. One of the reasons for this lack of productivity is the presence of weeds. Weeds have the potential to reduce yields of Fresh Fruit Bunches (FFB), so it is necessary to control them. The presence of weeds can diminish the yield of FFB; therefore, weed control is essential. Proper weed control can enhance FFB productivity. In weed control, appropriate steps are required, starting from planning, organizing, applying, and monitoring. The internship was conducted at Surya Adi Estate and Mesuji Estate, Sampoerna Agro, South Sumatra, where I served as KHL, a foreman's assistant, and an assistant supervisor. The KHL handled all technical aspects in the field, the foreman's assistant assisted the foreman in both technical and managerial tasks, and the assistant supervisor aided the assistant in managerial aspects. Primary data observation involved analyzing weed vegetation at various growth stages. The internship results indicated the application of manual and chemical weed control in accordance with company standards. The observations revealed that broadleaf weeds, such as Mucuna bracteata DC and Mikania micrantha Kunth, dominated at the TBM growth stage. Clidemia hirta D. Don, Ageratum conyzoides L., and Asystasia gangetica (L.) were prevalent at the young, adolescent, and mature stages of oil palm growth (TM). Among grassy weeds, Panicum sarmentosum Roxb was the dominant species at the TBM stage, while Cyperus rotundus L. was the most common sedge weed at the TBM growth stage, Produktivitas minyak kelapa sawit Indonesia belum maksimal. Salah satu penyebab kurangnya produktivitas yaitu gulma. Keberadaan gulma dapat menghilangkan hasil pada TBS sehingga gulma perlu dikendalikan. Pengendalian gulma yang tepat dapat meningkatkan produktivitas TBS. Dalam pengendalian gulma perlu langkah yang tepat mulai dari perencanaan, pengorganisasian, pengaplikasian, dan pengawasan. Magang bertujuan meningkatkan kemampuan teknis dan manajerial dalam budidaya di perkebunan kelapa sawit terutama dalam melakukan manajemen pengendalian gulma. Magang dilakukan di Kebun Surya Adi dan Kebun Mesuji, Sampoerna Agro Sumatera Selatan dengan menjadi KHL, pendamping mandor, dan pendamping asisten. KHL melakukan semua aspek teknis di lapangan, pendamping mandor membantu tugas mandor dalam aspek teknis dan manajerial, pendamping asisten membantu tugas asisten dalam aspek manajerial. Pengamatan data primer dengan melakukan analisis vegetasi gulma pada berbagai umur. Hasil magang menunjukkan aplikasi pengendalian gulma manual dan kimia sesuai dengan standar perusahaan. Hasil pengamatan menunjukkan jenis gulma yang ditemukan didominasi oleh daun lebar, seperti Mucuna bracteata DC, Mikania micrantha Kunth. pada umur tanam TBM. Clidemia hirta D. Don, Ageratum conyzoides L., dan Asystasia gangetica (L.) pada umur tanam TM muda, TM remaja, dan TM tua. Untuk jenis gulma rumput, yang mendominasi di umur tanam TBM yaitu Panicum sarmentosum Roxb. Jenis gulma teki paling banyak di umur tanam TBM yaitu spesies Cyperus rotundus L
Keyword: application, dominance, organization, planning, supervision

Judul: Synthesis of Molybdenum Trioxide (MoO3) by Electrochemical Method for Electrochromics Application
Abstrak: Molybdenum trioxide (MoO3) thin films have been deposited on glass substrates by electrochemical method using ammonium heptamolybdate tetrahydrate ((NH4)6Mo7O244H2O). The films were deposited onto glass substrates as the control temperature at 25○C and annealing treatment at 350○C for 30 mins. The MoO3 thin films were investigated by UV-Vis, X-ray diffraction techniques (XRD), Scanning Electron Microscopy (SEM). The JCPDS card show that orthorhombic MoO3 (α- phase) has been formed. Molybdenum trioxide MoO3 formation was also confirmed by JCPDS card no. 35-0609. The SEM photographs revealed that the spherical and rod-like morphology and their grains size increased with increasing of heating temperatures. The measurement results show that the MoO3 thin film prepared at 350°C transmited about 80% of the visible spectrum. The effect of different heat treatments on surface morphology, thickness and optical properties of the films are discussed in this thesis.
Keyword: Institut Pertanian Bogor, Bogor Agricultural University, IPB, Electrophoretics, electrodeposide, electrochromics, electrochromic materials, electrochromic mechanism