Judul: Community Structure of Plankton in Bojonegara Coastal Area, Banten Bay
Abstrak: Perairan pantai Bojonegara mendapat tekanan antopogenik yang tinggi melalui kegiatan industri, pemukiman, dan pembangunan infrastruktur. Tekanan antropogenik tersebut dapat memberikan dampak buruk bagi ekosistem perairan. Penelitian ini bertujuan menganalisis struktur komunitas plankton di wilayah perairan pantai Bojonegara. Penelitian dilakukan pada Bulan Januari, Februari, Agustus, September, dan Oktober 2020 pada 6 stasiun pengambilan data. Analisis data meliputi kelimpahan, indeks keanekaragaman, keseragaman, dominansi, regresi linear, principle component analysis, dan indeks similaritas Bray-Curtis. Parameter perairan yang mendukung kehidupan plankton di Bojonegara adalah salinitas, pH, nitrat, dan fosfat. Hasil penelitian menunjukkan bahwa fitoplankton didominasi oleh Bacillariophyceae dan Cyanophyceae, sedangkan zooplankton didominasi oleh Malacostraca dan Ciliata. Kelimpahan fitoplankton berkisar antara 3,0x10^5 – 8,7x10^5 sel/L, sedangkan zooplankton berkisar antara 2,8x10^4 – 9,9x10^4 ind/L. Plankton memiliki indeks keanekaragaman sedang, indeks keseragaman sedang, dan tidak terjadi dominansi. Struktur komunitas plankton menunjukkan bahwa perairan ini mendapat tekanan ringan dari lingkungan., Bojonegara coastal waters are subject to high anthropogenic pressure through industrial activities, residences, and infrastructure development. This anthropogenic pressure can harm aquatic ecosystems. This study aimed to analyze the plankton community structure at Bojonegara coastal area. This study conducted in January, February, August, September, and October 2020 at six data collecting stations. Data analysis included abundance, diversity, evenness, dominance, linear regression, principle component analysis, and Bray-Curtis similarity index. Water parameters show that salinity, pH, nitrate, and phosphate support plankton life in Bojonegara. Study result showed that phytoplankton are dominanted by Bacillariophyceae and Cyanophyceae, while zooplankton are dominated by Malacostraca and Ciliata. Phytoplankton abundance varied 3,0x10^5 – 8,7x10^5 cells / L, while zooplankton abundance varied 2,8x10^4 - 9,9x10^4 ind / L. Plankton has moderate diversity index, moderate evenness index, and no species dominance. The plankton community structure shows that Bojonegara waters are receiving light pressure from the environment.
Keyword: Bojonegara, community structure, plankton

Judul: Plankton Community Structure in Bojonegara Beach and Surrounding Waters, Banten Bay
Abstrak: Teluk Banten mendapat tekanan dari industri dan penambangan pasir. Salah satu daerah yang banyak dimanfaatkan adalah Kecamatan Bojonegara. Tekanan ini dapat memicu perubahan kualitas perairan. Perubahan parameter fisika dan kimia dapat memengaruhi kehidupan biota akuatik, salah satunya plankton. Penelitian ini bertujuan menganalisis keterkaitan keberadaan plankton dengan parameter fisika dan kimia perairan. Penelitian ini dilakukan selama tiga bulan, mulai dari Oktober hingga Desember 2019 pada enam stasiun. Penelitian menunjukkan bahwa hasil Analisis Komponen Utama (PCA) membentuk dua hingga tiga kelompok kondisi perairan yang dicirikan oleh keberadaan Bacillariophyceae, Cyanophyceae, Dinophyceae, Chrysophyceae, dan Chlorophyceae. Biplot PCA zooplankton membentuk dua kelompok, yaitu protozoa dan rotifera. Berdasarkan struktur komunitas yang terbentuk pada musim hujan terlihat bahwa plankton masih dapat tumbuh dengan baik pada lokasi dan waktu pengamatan. Struktur komunitas fitoplankton dan zooplankton di perairan Bojonegara mencerminkan kondisi yang relatif kurang stabil, yang dipengaruhi oleh kondisi salinitas dan fosfat total., Banten Bay is under pressure from industry and sand mining. One area that is widely used is Bojonegara. This pressure can trigger changes in water quality. Changes in physical and chemical parameters can affect the life of aquatic biota, one of which is plankton. This study aims to analyze the relationship between the presence of plankton with physical and chemical parameters of the waters. This research was conducted for three months, from October to December 2019 at six stations. The research shows that the results of PCA form two to three groups of water conditions characterized by the presence of Bacillariophyceae, Cyanophyceae, Dinophyceae, Chrysophyceae, and Chlorophyceae. Biplot PCA zooplankton form two groups, namely protozoa and rotifers. Based on the community structure formed during the rainy season, it shows that plankton still grow well at the location and time of observation. The community structure of phytoplankton and zooplankton in Bojonegara waters reflects a relatively unstable condition, which is influenced by conditions of total salinity and phosphate.
Keyword: Bojonegara, Plankton, Struktur komunitas, Teluk Banten

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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