Judul: Study of Economic Value and Sustainability of Mangrove Ecosystem Management in Angke Kapuk Nature Tourism Park
Abstrak: Konversi lahan mangrove menjadi peruntukkan lain kerap kali terjadi di Indonesia, tidak terkecuali di Provinsi DKI Jakarta. Salah satu lahan mangrove yang berhasil dipertahankan sebagai lokasi ekowisata oleh Pemerintah Provinsi DKI Jakarta adalah Taman Wisata Alam (TWA) Angke Kapuk. Selain mempertahankan fungsi ekosistem mangrove sebagai penyedia jasa lingkungan, keberadaan TWA Angke Kapuk juga memiliki banyak kegunaan baik secara langsung maupun tidak langsung bagi wisatawan dan masyarakat sekitar. Penelitian ini bertujuan untuk (1) mengkaji kondisi ekosistem mangrove di TWA Angke Kapuk, (2) mengestimasi nilai ekonomi total dari ekosistem mangrove di TWA Angke Kapuk, (3) menganalisis status keberlanjutan ekosistem mangrove di TWA Angke Kapuk. Metode penelitian yang digunakan adalah studi kasus, sedangkan metode analisis yang digunakan adalah analisis deskriptif kuantitatif, valuasi ekonomi, Travel Cost Method (TCM), dan Rapid Appraisal of Mangrove Forest (Rap_Mforest). Hasil penelitian menunjukkan kondisi ekosistem mangrove TWA Angke Kapuk lebih baik setelah adanya rehabilitasi dilihat dari pertambahan luas tutupan vegetasi, jenis, kerapatan, serta perubahan pemanfaatan ekosistem mangrove. Hasil estimasi nilai ekonomi total ekosistem mangrove TWA Angke Kapuk yaitu sebesar Rp17.943.600.572/tahun atau Rp179.759.573/ha/tahun. Status keberlanjutan ekosistem mangrove TWA Angke Kapuk memiliki status kurang berkelanjutan untuk dimensi ekologi (50,23), sedangkan untuk dimensi ekonomi (64,83), dimensi sosial (56,95), dan dimensi kelembagaan (53,75) memiliki status cukup berkelanjutan. Pengelolaan TWA Angke Kapuk perlu ditingkatkan agar ekosistem mangrove dapat mencapai status keberlanjutan baik., Conversion of mangrove land into other uses often occurs in Indonesia, including in Special Capital Region of Jakarta. One of the mangrove lands that has been successfully preserved as an ecotourism area by the Jakarta Provincial Government is the Angke Kapuk Nature Tourism Park (NTP). Besides to maintain its function as an environmental service providers, the existence of Angke Kapuk NTP is also directly and indirectly useful for tourists and the surrounding community. This research aims to (1) examine the condition of mangrove ecosystem in Angke Kapuk NTP, (2) estimate the total economic value of mangrove ecosystem in Angke Kapuk NTP, and (3) analyze the sustainability status of mangrove ecosystem in Angke Kapuk NTP. The research method used in this research is case study, while the analytical methods used are quantitative descriptive analysis, economic valuation, Travel Cost Method (TCM), and Rapid Appraisal of Mangrove Forest (Rap_Mforest). The results of the research showed that the condition of mangrove ecosystem after rehabilitation is in a better condition, which can be seen from the improvement in the area of vegetation cover, type, density, and appropriate utilization of mangrove ecosystem in Angke Kapuk NTP. The total economic value of mangrove ecosystem in Angke Kapuk NTP is Rp17.943.600.572 per year or Rp179.759.573 per hectare per year. The sustainability analysis of mangrove ecosystem in Angke Kapuk NTP are classified as less sustainable for the ecological dimension (50,23), while for other dimensions which consist of the economic dimension (64,83), the social dimension (56,95), and the institutional dimension (53,75) are classified as quite sustainable. Therefore, the management of Angke Kapuk NTP needs to be improved in order to obtain a good sustainability status of the mangrove ecosystem.
Keyword: konversi lahan mangrove, Rap_Mforest, status keberlanjutan, TCM, valuasi ekonomi

Judul: Analysis of Mangrove Damage and Rehabilitation Steps in the Angke Kapuk Protected Forest, North Jakarta
Abstrak: Ekosistem mangrove merupakan salah satu habitat alami pada kawasan pesisir yang sangat rentan terhadap ancaman alam baik dari darat maupun laut. Selain disebabkan oleh alam, ancaman terhadap ekosistem mangrove juga dapat disebabkan oleh kegiatan manusia. Penelitian ini bertujuan untuk menganalisis tingkat kerusakan mangrove dan potensi rehabilitasi mangrove di Hutan Lindung Angke Kapuk, Jakarta Utara. Penelitian ini dilaksanakan pada bulan Desember 2021 hingga Januari 2022 dengan lokasi penelitian terdiri dari tiga stasiun yang meliputi tiga tipe yaitu teluk, muara sungai, dan pantai reklamasi. Kerapatan dan penutupan mangrove di Angke Kapuk tergolong dalam kriteria rendah, kecuali stasiun 1 yang memiliki kerapatan sangat tinggi dan penutupan mangrove dalam kriteria rendah. Kondisi ini mengakibatkan nilai indeks kesehatan mangrove menjadi sedang pada stasiun 1, sedangkan stasiun 2 dan 3 tergolong kategori rendah. Indeks kualitas lingkungan pada ketiga stasiun tergolong kedalam kategori tinggi. Berdasarkan nilai kedua indeks tersebut, tingkat kerusakan pertumbuhan mangrove tergolong tinggi dan kerusakan lingkungan mangrove tergolong rendah dan diketahui matriks rehabilitasi mangrove dengan strategi replantasi. Strategi replantasi tersebut mempertimbangkan zonasi dalam penentuan jenis mangrove yang ditanam., Mangrove , one of the natural ecosystems in coastal areas is very vulnerable to n threats both from land and sea. Besides being caused by nature, threats to mangrove ecosystems can also be caused by human activities. This study aims to analyze the level of damage to mangroves and the potential for mangrove rehabilitation in the Angke Kapuk Protection Forest, North Jakarta. This research was carried out from December 2021 to January 2022 with research locations consisted of three stations covering three types, namely bays, river mouths, and reclamation beaches. The density and cover of mangroves in Angke Kapuk are classified as low criteria, except for station 1 which has a very high density and mangrove cover is in the low criteria. This condition causes the mangrove health index value to be moderate at station 1, while stations 2 and 3 are in the low category. The environmental quality index at the three stations belongs to the high category. Based on the values of these two indices, the level of damage to mangrove growth is classified as high and environmental damage to mangroves is classified as low and it is known that the mangrove rehabilitation matrix with a replantation strategy. The replantation strategy considers zoning in determining the type of mangrove to be planted
Keyword: kesehatan mangrove, kualitas lingkungan, mangrove, rehabilitasi, environmental quality, mangrove health, rehabilitation, mangroves

Judul: Construction of Strongly Optimal Binary Linear Code with Minimum Distance 9 and 11
Abstrak: A binary linear code of length n over q F is a subspace of n q F . A code has three parameters that attached to it, namely length, dimension, and minimum distance. A code with length n, dimension k and minimum distance d is often called [n, k, d ]-code. Usually, when two parameters are given, then we want to find a code that has the best value for the last parameter. Based on Gilbert- Varshamov bound, if a [n, k, d ]-code exists and can not be expanded, we call it a strongly optimal code. In this paper, we construct strongly optimal code with minimum distance 9 and 11. In constructing the code, we created a theorem and algorithm based on Gilbert-Varshamov bound before we implement the algorithm to MAPLE programming language. Because of computational limitations, the program can only construct up to k = 10 for d = 9 and k = 12 for d = 11.
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