Judul: Estimasi Stok dan Emisi Karbon Mangrove di Pulau Pari, Kabupaten Kepulauan Seribu, DKI Jakarta
Abstrak: Strategi mitigasi perubahan iklim global dapat dilakukan salah satunya melalui pemanfaatan ekosistem blue carbon. Ekosistem mangrove menjadi salah satu ekosistem pesisir yang memiliki potensi menyerap dan menyimpan karbon. Pulau Pari, Kepulauan Seribu merupakan salah satu kawasan pesisir dengan potensi ekosistem mangrove tinggi. Penelitian ini dilakukan untuk menghitung estimasi stok dan serapan karbon mangrove alami di Pulau Pari. Penelitian dilakukan di pada lima stasiun di utara, timur, dan barat Pulau Pari selama periode Oktober 2023 hingga Mei 2024. Stok dan serapan karbon dihitung pada carbon pool biomassa dan sedimen mangrove. Berdasarkan hasil penelitian, diketahui mangrove di Pulau Pari berada pada kondisi baik dengan kerapatan mencapai 1363 ind/ha. Mangrove Pulau Pari memiliki stok karbon total sebesar 28.791,1143 ton C dan serapan karbon dioksida total sebesar 105.567,5291 ton CO2 e. Stasiun satu memiliki nilai stok dan serapan karbon tertinggi yang didukung kelimpahan, biomassa, dan jenis substrat. Kerapatan memiliki hubungan yang kuat dengan biomassa, stok karbon, dan serapan karbon dioksida pada ekosistem mangrove., One of the strategies to mitigate global climate change is through the use of blue carbon ecosystems. The mangrove ecosystem is one of the coastal ecosystems that has the potential to absorb and store carbon. Pulau Pari, Kepulauan Seribu is a coastal area with high potential for mangrove ecosystems. This research was conducted to calculate estimates of natural mangrove carbon stock and uptake on Pulau Pari. The research was conducted at five stations in the north, east and west of Pari Island during the period October 2023 to May 2024. Carbon stocks and uptake were calculated from the carbon pool of biomass and mangrove sediment. Based on research results, it is known that the mangroves on Pulau Pari are in good condition with a density of 1363 ind/ha. Pari Island mangroves have a total carbon stock of 28.791,1143 tons C and a total carbon dioxide uptake of 105.567,5291 tons CO2 e. Station one has the highest carbon stock and uptake values supported by abundance, biomass and substrate type. Density has a strong relationship with biomass, carbon stock and carbon dioxide uptake in mangrove ecosystems.
Keyword: mangrove, blue carbon, Pari Island

Judul: Biomass and Carbon Stock Mangrove and Pandan Laut Ecosystems (Pandanus tectorius) on North Pari Island, Seribu Islands, DKI Jakarta
Abstrak: Kenaikan suhu atmosfer saat ini telah menjadi isu hangat bagi seluruh dunia yang di sebabkan karena peningkatan konsentrasi karbon dioksida (CO2) dan berdampak pada perubahan iklim. Analisis nilai biomassa stok karbon yang tersimpan dilaksanakan pada 20 November – 26 November 2023 di Utara Pulau Pari, Kepulauan Seribu DKI Jakarta dari 5 titik pengamatan yang berbeda, yaitu 3 pengamatan di ekosistem mangrove dan 2 pengamtan di ekositem pandan laut. Pengambilan sampel dilakukan dengan menggunakan metode plot lingkaran. Pengukuran stok karbon dan biomassanya hanya didasarkan atas diameter batang. Nilai biomassa yang di dapat dibandingkan untuk menentukan lebih banyak manakah CO2 yang diserap untuk mengurangi emisi CO2 di kedua ekosistem pesisir. Ekosistem mangrove memiliki serapan karbon CO2 lebih besar daripada ekosistem pandan laut yaitu sebesar 1407 ton CO2/ha dan 10 ton CO2/ha, dikarenakan jumlah diameter dan jenis spesies yang ditemukan saat dilokasi lebih banyak dan mendominasi ekosistem mangrove daripada pandan laut yaitu sebesar 163 ind dan 26 ind., The rise in atmospheric temperature has now become a hot issue for the whole world caused by an increase in carbon dioxide (CO2) concentrations and an impact on climate change. Analysis of the value of stored carbon stock biomass will be carried out on November 20 – November 26, 2023 in the North of Pari Island, Seribu Islands DKI Jakarta from 5 different observation points, namely 3 observations in mangrove ecosystems and 2 observations in pandan laut ecosystems. Sampling is carried out using the circular square transect method. The measurement of carbon stocks and biomass is based only on the diameter of the rod. Biomass values can be compared to determine where more CO2 is absorbed to reduce CO2 emissions in both coastal ecosystems. Mangrove ecosystems have greater carbon CO2 absorption than pandan laut ecosystems, which are 1407 tons CO2/ha and 10 tons CO2/ha, because the number of diameters and types of species found when located is more and dominates mangrove ecosystems than sea pandanus, which is 163 ind and 26 ind.
Keyword: biomassa, mangrove, stok karbon, pandan laut, Pulau Pari

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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