Judul: Study of the Effectiveness of Boron Application in Peat Soil on Ginger Growth and Production
Abstrak: Kebakaran hutan dan lahan sering terjadi di Indonesia. Salah satu komitmen mitigasi bencana kebakaran lahan gambut adalah kolaborasi perusahaan dengan masyarakat melalui pengelolaan area greenbelt. Salah satu tanaman yang mempunyai potensi ekonomi yang baik dan berpeluang untuk dikembangkan pada greenbelt adalah jahe. Kondisi lahan gambut yang miskin unsur hara, khususnya unsur mikro, menjadi tantangan dalam budidaya jahe. Penelitian ini menguji pengaruh boron terhadap pertumbuhan jahe di tanah gambut. Percobaan menggunakan rancangan acak lengkap (RAL) faktor tunggal yang dilakukan dengan pemberian B pada lima taraf konsentrasi (0, 0.4, 0.6, 0.8, dan 1 ppm). Respon tanaman dilihat dari beberapa parameter seperti tinggi tanaman, jumlah dan total daun, jumlah anakan, bobot basah dan kering tanaman serta bobot rimpang. Pemberian B sebesar 0.4 ppm pada tanah gambut berpengaruh nyata terhadap pertumbuhan tinggi batang jahe. Pemberian B sebesar 0.4-0.6 ppm berpotensi meingkatkan hasil produksi rimpang, bobot basah dan bobot kering tanaman., Forests and land fires often occur in Indonesia. One commitment to mitigating peatland fire disasters is the collaboration of companies with the community through greenbelt-area management. One plant with good economic potential that can be developed in the greenbelt is ginger. However, the poor nutrient conditions in peatlands, especially microelements, present a challenge for ginger cultivation. Therefore, this study aimed to test the effect of boron on the growth of ginger in peat soil. The researcher used a single-factor completely randomized design (CRD) to administer B at five concentration levels (0, 0.4, 0.6, 0.8, and 1 ppm) to assess plant response. Plant height, number and total of leaves, number of tillers, wet and dry plant weights, and rhizome weight, were used to measure plant responses. Providing B at 0.4 ppm in peat soil was proven to be effective in increasing the height of ginger stems. Providing B at 0.4-0.6 ppm has the potential to increase rhizome production, wet weight and dry weight of plant.
Keyword: Fertilization, Nutrient imbalance, Soil nutrient

Judul: Application of PGPR (Plant Growth Promoting Rhizobacteria) and Membrane Bionanomaterials on Rice Germination as Agroforestry Opportunities in Peatlands
Abstrak: Laju degradasi lahan gambut di Indonesia yang semakin tinggi mengakibatkan produktivitas lahan semakin menurun. Hal tersebut berdampak pada pentingnya upaya optimalisasi lahan, salah satunya melalui pengembangan sistem agroforestri, serta pemilihan jenis tanaman adaptif. Padi Dendang merupakan salah satu varietas padi adaptif di lahan gambut. Penelitian ini bertujuan menganalisis sifat tanah gambut yang dimanfaatkan untuk agroforestri, dan pengaruhnya terhadap perkecambahan padi Dendang dengan aplikasi PGPR serta membran bionanomaterials melalui uji in vitro dan in vivo. Analisis data yang digunakan adalah RAL faktorial dua faktor, yakni satu dosis PGPR, dan bionanomaterials (BNMs) yaitu tandan kosong kelapa sawit aktivasi (TA) dan non-aktivasi (TN), serta batang kelapa sawit non-aktivasi (BN) dan lignoselulosa (BL) dengan masing-masing 3 konsentrasi (1%, 3%, dan 5%). Hasil penelitian menunjukkan bahwa pH tanah gambut sangat masam (3,60). Aplikasi PGPR dan BNMs mampu meningkatkan pH, N, P, K, Na, Ca, Mg, dan menurunkan kandungan Al. Pada uji in vitro, aplikasi PGPR berpengaruh nyata terhadap persen hidup, sedangkan BNMs berpengaruh sangat nyata pada kecambah normal dan abnormal, persen hidup, serta tinggi kecambah. Pada uji in vivo PGPR berpengaruh sangat nyata terhadap persen hidup benih dan tinggi kecambah, sedangkan BNMs berpengaruh sangat nyata terhadap daya kecambah dan potensi tumbuh maksimum., The rate of peatland degradation in Indonesia is getting higher, resulting in lower land productivity. This has an impact on the importance of land optimization efforts, one of which is through the development of agroforestry systems, as well as the selection of adaptive plant species. Dendang rice is one of the adaptive rice varieties in peatlands. This study aims to analyze the properties of peat soil used for agroforestry, and its effect on the germination of Dendang rice with the application of PGPR and membrane bionanomaterials in vitro and in vivo tests. The data analysis used was two-factor factorial RAL, namely one dose of PGPR, and bionanomaterials (BNMs) of namely activated (TA) and non-activated (TN) oil palm empty bunches, and non-activated oil palm trunks (BN). and lignocellulose (BL) with 3 concentrations (1%, 3%, and 5%), respectively. The results showed that the pH of the peat soil was very acidic (3.60). The application of PGPR and BNMs was able to increase pH, N, P, K, Na, Ca, Mg, and decrease Al content. In the in vitro test, PGPR application had a significant effect on the survival rate, while BNMs had a very significant effect on normal and abnormal sprouts, percent survival, and sprout height. In the in vivo test, PGPR had a very significant effect on the percentage of seed survival and germination height, while BNMs had a very significant effect on germination and maximum growth potential.
Keyword: membrane bionanomaterials, peat soil, paddy Dendang, PGPR, germination

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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