Judul: Kondisi Ekologis dan Pengelolaan Mangrove di SPTN III, Taman Nasional Kepulauan Seribu
Abstrak: Efektivitas pengelolaan mangrove sangat bergantung pengetahuan tentang kondisi mangrove dan lingkungannya, yang dapat diketahui dari indeks kesehatan mangrove dan indeks kualitas lingkungan mangrove. Penelitian ini bertujuan mengkaji kondisi ekologis, kesehatan dan lingkungan mangrove di daerah SPTN III (Pulau Karya, Pulau Panggang, dan Pulau Pramuka) TNKS untuk merumuskan strategi pengelolaannya. Penelitian ini dilaksanakan pada bulan Februari 2020. Analisis ekologi yang dilakukan adalah indeks kesehatan mangrove dan indeks kualitas lingkungan mangrove. Kerapatan mangrove kategori anakan di seluruh pulau termasuk kategori sangat padat, sedangkan kategori pohon dan semai hanya ditemukan di beberapa tempat saja. Secara umum nilai kualitas lingkungan mangrove menunjukkan kualitas lingkungan mangrove yang tinggi (baik). Indeks kesehatan mangrove di ketiga pulau termasuk dalam kategori kesehatan mangrove rendah (buruk), meskipun di beberapa tempat ditemukan mangrove kategori pohon dengan kerapatan yang padat. Berdasarkan hasil tersebut perlu dilakukan rancangan strategi berupa replantasi dan pengelolaan berbasis zonasi di wilayah SPTN III., The effectiveness of mangrove management is highly dependent on the knowledge of the condition of mangrove and their environment, which are represented by the mangrove health index and the mangrove environmental quality index. This study aimed to analyze the ecological condition of mangroves in the SPTN III area (Karya Island, Panggang Island, and Pramuka Island) Seribu Islands National Park area to determine the management strategy. This research was conducted in February 2020. The analysis carried out were mangrove health and mangrove environmental quality. The Mangrove density in the sapling category throughout the island was very dense category, while the tree and seedling growth categories are only found in a few places. The value of the mangrove environmental quality indicate that the environmental quality of the mangroves in the three islands was in high category (good). The mangrove health index in the three islands in other hand was low category (bad), though in some places mangroves showed densed density. Based on these results, mangrove replantation is the strategy mostly recommended for SPTN III.
Keyword: kesehatan mangrove, kualitas lingkungan, replantasi

Judul: Karakteristik dan Dampak Pengelolaan Ekosistem Mangrove Rehabilitasi di Kawasan Konservasi dan Wisata: Studi Kasus Pulau Pramuka dan Pulau Pari
Abstrak: Ekosistem mangrove memiliki manfaat ekologi maupun ekonomi. Namun, rentan terhadap kerusakan dan penurunan biodiversitas. Oleh sebab itu, pemahaman mengenai pengelolaan dan strategi rehabilitasi mangrove penting. Penelitian ini bertujuan menganalisis karakteristik pengelolaan ekosistem mangrove di kawasan konservasi dan wisata di Pulau Pramuka dan Pulau Pari, Kepulauan Seribu, pada November 2023–Februari 2024. Metode yang digunakan, yaitu melakukan wawancara secara purposive sampling, pengambilan data vegetasi mangrove, dan sampel makrozoobentos. Variabel yang dianalisis meliputi karakteristik pengelolaan (tata kelola, aturan lokal, strategi rehabilitasi, dan pengelolaan pasca tanam) dan dampak pengelolaan (cakupan mangrove rehabilitasi, kerapatan mangrove, dan keanekaragaman makrozoobentos). Hasil penelitian menunjukkan dua jenis mangrove di Pulau Pramuka (Rhizophora stylosa dan Rhizophora mucronata) dan empat jenis mangrove di Pulau Pari (Rhizophora stylosa, Rhizophora apiculata, Soneratia alba, dan Bruguiera cylinndrica). Tingkat kerapatan mangrove pada kedua pulau tergolong sangat padat (31.714-128.500 ind/ha). Kepadatan makrozoobentos di Pulau Pramuka dan Pulau Pari masing-masing sebesar 121 ind/m2 dan 189 ind/m2 dengan keanekaragaman sedang. Kerapatan mangrove berkorelasi positif dengan kepadatan makrozoobentos (r>0.9). Terdapat perbedaan pengelolaan mangrove di kedua pulau dari segi tata kelola, aturan lokal, pengawasan dan pemeliharaan pasca tanam., The mangrove ecosystem has both ecological and economic benefits. However, it is vulnerable to damage and biodiversity loss. Therefore, understanding mangrove management and rehabilitation strategies is crucial. This research aims to analyze the characteristics of mangrove ecosystem management in conservation and tourism areas on Pramuka Island and Pari Island, Kepulauan Seribu, from November 2023 to February 2024. The methods used include purposive sampling interviews, mangrove vegetation data collection, and macrozoobenthos sampling. The variables analyzed include management characteristics (governance, local regulations, rehabilitation strategies, and post-planting management) and management impact (rehabilitated mangrove coverage, mangrove density, and macrozoobenthos diversity). The research results show two types of mangroves on Pramuka Island (Rhizophora stylosa and Rhizophora mucronata) and four types on Pari Island (Rhizophora stylosa, Rhizophora apiculata, Soneratia alba, and Bruguiera cylindrica). The mangrove density on both islands is classified as very dense (31,714-128,500 ind/ha). The macrozoobenthos density on Pramuka Island and Pari Island is 121 ind/m2 and 189 ind/m2, respectively, with moderate diversity. Mangrove density positively correlates with macrozoobenthos density (r>0.9). There are differences in mangrove management between the two islands in terms of governance, local regulations, post-planting monitoring, and maintenance.
Keyword: mangroves, macrozoobenthos, management, rehabilitation

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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