Judul: Comparative of Pine Resin (Pinus merkusii) Productivity in Agroforestry and Non agroforestry Patterns in KPH Malang, East Java.
Abstrak: Agroforestri merupakan suatu sistem pengelolaan tanaman hutan yang dikombinasikan dengan pertanian untuk mengoptimalkan lahan yang ada, namun dalam suatu pengelolaan tidak semua menggunakan pola tanam agroforestri, ada yang hanya menggunakan pola tanam murni maupun campur. Penelitian ini bertujuan untuk mengetahui perbandingan jumlah getah pinus yang menggunakan pola tanam agroforestri dan non agroforestri, serta mengetahui faktor yang mempengaruhi perbandingan hasil panenan getah pinus pada pola tanam agroforestri dan non agroforestri. Hasil penelitian menunjukkan produktivitas getah pinus di KU IV, V, VI pada agroforestri lebih banyak dibandingkan non agroforestri yakni sebesar 35,52 gram/pohon/hari, 48,17 gram/pohon/hari, dan 76,48 gram/pohon/hari untuk agroforestri serta 31,93 gram/pohon/hari, 36,24 gram/pohon/hari, dan 61,19 gram/pohon/hari untuk pola non agroforestri. Perbedaan pada selisih hasil produktivitas getah pinus hanya sedikit sehingga hasil uji menunjukkan pola agroforestri dan non agroforestri tidak memberikan pengaruh yang signifikan terhadap produktivitas. Produktivitas getah pinus dipengaruhi oleh ketinggian tempat tumbuh, unsur hara, sifat genetis dari pohon, dan tenaga penyadap. Kata kunci : agroforestri, getah, non agroforestri, pinus, produktivitas, Agroforestry is a forest management system that combine between agriculture and forestry to optimize the existing land. However, the agroforestry is actually not only consisted of pure planting pattern, but also non agroforestry. This study aims to compare the pine resin production using agroforestry and non agroforestry planting patterns, and finally to determine some variation factors that influence pine resin results in both planting patterns. The results of this study shows that the productivity of pine resin of KU IV, V, VI in agroforestry is higher than non agroforestry, namely 35,52 grams/tree/day, 48,17 grams/tree/day, and 76,48 grams/tree/day for agroforestry and 31,93 grams/tree/day, 36,24 grams/tree/day, and 61,19 grams/tree/day for non agroforestry, respectively. The difference in pine resin productivity is only slight, so the test results show that agroforestry and non agroforestry patterns have no significant effect on productivity. Pine resin productivity is influenced by the altitude of the growing place, nutrients, genetic properties of the stand, and tapper labor. Keywords: agroforestry, non agroforestry, pine, productivity, resin
Keyword: agroforestry, non agroforestry, pine, productivity, resin

Judul: Post-recovery Pine Tapping Productivity at KPH Bogor Regional Division of West Java and Banten Perum Perhutani
Abstrak: Permintaan produksi getah pinus terus meningkat, namun produksi getah pinus menurun. Salah satu penyebabnya yaitu karena tegakan pinus mengalami jenuh sadap (belum saatnya untuk ditebang namun bidang sadap sudah habis). Produktivitas getah pinus pascapemulihan yaitu sadapan pinus yang dilakukan pada bidang sadap yang telah mengalami penutupan luka belum diketahui. Penelitian ini bertujuan untuk mengukur persentase pemulihan bidang sadapan pinus metode quarre dan menganalisis produktivitas sadapan pinus pascapemulihan pada kedua kelas umur pohon. Rancangan percobaan yang digunakan adalah rancangan acak kelompok terdiri dari dua perlakuan yaitu sadapan pascapemulihan dan kontrol sedangkan kelompok yaitu tegakan pinus kelas umur (KU) IV dan IX. Hasil penelitian menunjukkan rata-rata pemulihan bidang sadapan pinus KU IX lebih tinggi dibandingkan KU IV. Rata-rata produktivitas getah pinus (g/pohon/hari) perlakuan pascapemulihan lebih rendah dibandingkan kontrol pada kedua kelas umur yaitu KU IV dan KU IX perlakuan pascapemulihan berturut-turut 8,11 g/pohon/hari dan 9,15 g/pohon/hari sedangkan perlakuan kontrol berturut-turut 11,42 g/pohon/hari dan 10,59 g/pohon/hari. Perlakuan (pascapemulihan dan kontrol) sadapan getah pinus menghasilkan produktivitas yang berbeda sedangkan kelas umur menghasilkan produktivitas yang sama., The demand for pine resin continues to increase along with the declining of pine resin production. One of the reasons is because the pine trees have become saturated with tapping (it is not proper yet to cut down, but the tapping fields have run out). Post-recovery pine resin productivity, namely pine tapping in a tapping area that had undergone closure of the tapping wound not yet known. This study aimed to measure the percentage of pine tapping field recovery using the quarre method and to analyze the productivity of post-recovery pine resin in both age classes of trees. The experimental design used a randomized block design consisting of two treatments, namely post-recovery and control, while the group consisted of pine stands of age class IV and IX. The results showed that the average recovery of the pine tapping field in age class IX was higher than age class IV. The average productivity of pine resin (g/tree/day) in post-recovery treatment was lower than the control in both age classes, namely age class IV and IX in post-recovery treatment, respectively 8.11 g/tree/day and 9.15 g/tree/day while the control treatments were 11.42 g/tree/day and 10.59 g/tree/day, respectively. Treatments (post-recovery and control) on tapped pine resin had a different productivity, while the groups (age class) had the same productivity.
Keyword: post-recovery, pine resin, productivity, tapping field recovery

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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