Judul: Potential Combination of Miko-seedcookies and Biological Agents on Merbau Seeds (Intsia bijuga) in Post-mining Land
Abstrak: Penggunaan teknologi direct seeding dengan media tanam Miko-seedcookies (MSC) masih terbatas sehingga perlu ditingkatkan lagi melalui kombinasi dengan agens hayati agar dapat memberikan keberhasilan bagi pertumbuhan tanaman di lahan terdegradasi seperti lahan pascatambang. Penelitian ini bertujuan menganalisis pengaruh aplikasi Miko-seedcookies (MSC), mengetahui dosis agen hayati yang efektif serta mengetahui tingkat serangan hama dan penyakit benih Merbau. Bahan dari penelitian ini terdiri dari agen hayati Gliocladium sp. (Gli) dan Trichoderma hamatum (Tri). Penelitian ini menggunakan rancangan acak kelompok (RAK) dengan satu faktor yaitu dosis agen hayati dengan 3 ulangan dan 4 perlakuan yang terdiri dari MSC, MSC + GliTri 1%, MSC + GliTri 2% dan MSC + GliTri 5%. Hasil penelitian menunjukkan perkecambahan dan daya hidup tidak dipengaruhi oleh media tanam MSC dan dosis agen hayati namun berpengaruh pada tinggi, diameter, jumlah daun serta tingkat serangan hama dan penyakit pada Merbau (Intsia bijuga). Hama dan penyakit yang ditemukan pada tanaman Merbau berupa kutu, hawar daun, bercak daun, dan daun mengkerut dengan intensitas serangan tergolong ringan. Dosis agen hayati 1% dan 2% menunjukkan pengaruh yang paling baik terhadap pertumbuhan tanaman. Persen kolonisasi mikoriza berada pada rentang 16,32%-30% yaitu kelas rendah – sedang., Direct seeding technology with Miko-seedcookies (MSC) planting media is still limited and needs further enhancement by combining biological agents to provide successful plant growth.This study aims to analyze the effect of Miko-seedcookies (MSC) application, determine the effective dosage of biological agents, and assess the level of pest and disease attacks on Merbau seeds. The materials for this study consist of the biological agents Gliocladium sp. (Gli) and Trichoderma hamatum (Tri). This research used a randomized block design (RBD) with one factor,the dosage of biological agents with three replications and four treatments. The results showed that germination and viability were not affected by the MSC planting media and dosage of biological agents. However, they influenced the height, diameter, number of leaves, and the level of pest and disease attacks on Merbau (Intsia bijuga). Pests and diseases found on Merbau plants include aphids, leaf blight, leaf spots, and leaf curling. The 1% and 2% dosages of biological agents showed the best influence on plant growth. The percentage of mycorrhizal colonization ranged from 16.32% to 30%, which is a moderate level.
Keyword: Direct seeding, Glioclaldium sp., Lahan terdegradasi, Mikoriza, Trichoderma hamatum

Judul: Direct Seeding of Jackfruit Seeds (Artocarpus heterophyllus Lamk) with Miko-seedcookies in The Former Limestone Mining Land
Abstrak: Upaya untuk meningkatkan kegiatan reklamasi lahan bekas tambang telah banyak mendapat terobosan seperti dengan direct seeding, hydroseeding, seedball, dan dengan aplikasi mikoriza. Miko-seedcookies (MSC) merupakan salah satu media tanam alternative yang dapat digunakan pada teknik direct seeding. Tujuan penelitian ini adalah untuk menganalisis pengaruh penggunaan MSC pada pertumbuhan benih nangka serta untuk menentukan ukuran optimal MSC yang dapat meningkatkan keberhasilan tumbuh benih nangka (Artocarpus heterophyllus Lamk). Penelitian menggunakan Rancangan Acak Lengkap (RAL). Penggunaan MSC berukuran 7 cm berpengaruh nyata terhadap daya kecambah mencapai 100%, daya hidup mencapai 96,33%, dan persen kolonisasi mikoriza mencapai 35,78%. Penggunaan MSC berukuran 7 cm menunjukkan pengaruh yang paling baik terhadap pertumbuhan benih nangka, Many advancements in the reclamation of ex-mining ground have occurred, including direct seeding, hydroseeding, seedballs, and mycorrhiza application. Miko-seedcookies (MSC) are a planting media alternative that may be utilized in the direct seeding technique. The aims of this research are to analyze the effect of using MSC on jackfruit growth and to determine the optimal size of MSC that can increase the success of jackfruit (Artocarpus heterophyllus Lamk) growth. The research used a Completely Randomized Design (CRD). MSC measuring 7 cm had a substantial influence on seeds germination reaching 100%, survival rate reaching 96,33%, and mychorrizal colonization reaching 35,78%. The aplication of MSC (7 cm) had the greatest influence on jackfruit growth
Keyword: Direct seeding, ex-limestone mining land, jackfruit, miko-seedcookies

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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