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"Telah dilakukan penelitian mengenai struktur komunitas dan sebaran spasial Bivalvia serta hubungannya dengan karakteristik lingkungan di Teluk Katania, Seram Barat, Maluku Tengah. Ada 5 stasiun penelitian yaitu : Pelita Jaya 1, Pelita Jaya 2, Pulau Buntal, Pulau Tatumbu, dan Pulau Burung. Anadara maculafa merupakan jenis Bivalvia yang kepadatannya tertinggi (2,5 individu/m2). Nilai H' (indeks keanekaragaman) Bivalvia tertinggi ada di Pulau Burung (H' = 0,958) dan terendah di Pulau Buntal (H' = 0,624). Indeks kemerataan J' tertinggi (J' = 0,843) terdapat di Pelita Jaya 1. indeks kesamaan Morisita C tertinggi adalah antara Pelita Jaya 2 dan Pulau Buntal (C = 0,92). Kondisi substrat di Pelita Jaya 2 dan Pulau Buntal mempunyai persentase Lumpur yang tinggi. Dengan analisis cluster, 5 stasiun penelitian terbagi menjadi 2 kelompok. Kelompok I terdiri atas stasiun Pelita Jaya 2 dan Pulau Buntal kemudian kelompok II terdiri atas Pelita Jayal, Pulau Tatumbu, dan Pulau Burung. Analisis diskriminan dengan faktor lingkungan substrat pasir halus dan lumpur juga membagi kelima stasiun menjadi dua kelompok yang sama seperti pada analisis cluster. Substrat lumpur mempunyai kontribusi yang tinggi (96,3 %). Tellina sp merupakan jenis yang penyebarannya luas sebab selalu hadir di setiap stasiun penelitian. Hasil analisis faktorial koresponden membentuk enam kelompok. Penyebaran spasial jenis jenis Bivalvia di 5 stasiun dari hasil analisis tersebut berdasarkan pada kepadatan tertinggi dari jenis jenis tertentu (lima kelompok) dan berdasarkan jenis-jenis yang selalu hadir di setiap stasiun (satu kelompok).

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Bivalvia, also known as Pelecypoda, is the second largest class in phylum Mollusca. This group has 28.000 species (Barth & Broshear, 1982) and about 1000 species of Bivalvia live in Indonesian waters (Nontji, 1987). Information about Bivalvia in Kotania Bay has not been known well. Based on those fact, a research on the community structure and spatial distribution of Bivalve in the waters of Kotania Bay was conducted in February 1996. The aim of study was to find out the relationship between Bivalvia community structure with environmental factors in the waters of Kotania Bay. The spatial distribution of Bivalvia in several small islands in Kotania Bay was also studied. Hopefully, the results can be used as basic information for father research.

The research was conducted in five stations, i.e. Pelita Jaya 1, Pelita Jaya 2, Buntal Island, Tatumbu Island, and Burung Island. The sampling method used in the study was belt transact. The water conditions measured were water temperature, salinity, and pH. The substrates were characterized by the sediment fractions. Temperatures in the research stations ranged between 29.5°C and 31 °C, the range of pH is between 7 and 8.4. Water salinities in the research stations varied between 22 % and 30 %. Substrates in the research stations mostly contained sand with the very high percentage of very coarse sand. Silt was the smallest fraction found in the substrate.

In five research stations, 32 species of Bivalvia belonging to 15 families were collected. Anadara maculata had the highest density (2.5 individulm2) of all Bivalvia species found. The highest H' value (diversity index) of Bivalvia was in Burung Island (H' = 0.958) and the lowest was in Buntal Island (H' = 0.624). The highest evenness index J' = 0.843 was found in Pelita Jaya 1. The highest similarity index was shown by Pelita Jaya 2 and Buntal Island. Substrates in Pelita Jaya 2 and Buntal Island were dominated by silt.

Cluster analysis at five research stations divided the stations into two groups. Group I, defined by Pelita Jaya 2 and Buntal Island. Group ii, defined by Pelita Jaya 1, Tatumbu Island, and Burung Island. Discriminant analysis based on two environmental factors, i.e. very fine sand and silts, also divided the stations into two similar groups as cluster analysis did. The silt factor had high contribution (96.3%) in separating the stations.

Factorial correspondence analysis classified the species of Bivalvia into six groups. Based on the highest density of the certain species (five groups) and on the common species found in all stations (one group). Among the species collected Tellina sp was the common species found in the five stations. Spondylus squamosus, Trachydarium subrugosum, and Vulsella vulsella were found only in Pelita Jaya 2. Pitar subpellucidus, Septifer hi/ocular-is, Fimbria fmbriata and Chama pacifica were found only in Burung island. The species of Bivalvia only found in Pelita Jaya 1 were Atrina vexillum, Tellina staurella, Chama ruderalis, Limaria fragilis, and Clycymeris pectunculus."

"Telah dilakukan penelitian tentang sebaran spasial fitoplankton di lokasi budidaya kerang hijau (Perna viridis) Kamal Muara, Jakarta Utara. Penelitian bertujuan mengetahui kelimpahan dan sebaran spasial fitoplankton, serta parameter lingkungan yang memengaruhi. Berdasarkan peta sebaran, kelimpahan Bacillariophyceae dan Dinophyceae lebih tinggi pada stasiun-stasiun yang dekat dengan daratan (Stasiun 1 dan Stasiun 2), sedangkan kelimpahan Cyanophyceae ditemukan lebih tinggi pada stasiun-stasiun yang jauh dari daratan (Stasiun 5 dan Stasiun 9). Analisis Regresi Multivariat menunjukkan bahwa seluruh parameter lingkungan terukur berpengaruh terhadap kelimpahan fitoplankton. Nilai korelasi Spearman menunjukkan bahwa kelimpahan Bacillariophyceae paling dipengaruhi oleh pH, kelimpahan Dinophyceae paling dipengaruhi oleh salinitas, sedangkan kelimpahan Cyanophyceae paling dipengaruhi oleh fosfat.

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Research on the spatial distribution of phytoplankton has been held in the green mussel aquaculture area (Perna viridis) Kamal Muara, North Jakarta. The research aim to determine the abundance and spatial distribution of phytoplankton and environmental parameters influenced. Based on distribution maps, the abundance of Bacillariophyceae and Dinophyceae were highest at stations near mainland (Station 1 and Station 2), whereas Cyanophyceae was at farther stations (Station 5 and Station 9).

Regression Multivariate analysis showed that all measured environmental parameters were influencing the abundance of phytoplankton. Spearman correlation values indicate that the abundance of Bacillariophyceae were most influenced by pH, Dinophyceae by salinity, whereas Cyanophyceae by phosphate."

"Pola sebaran dan perilaku bintang laut intertidal di Teluk Gilimanuk dan Pantai Cekik diteliti dari September 2012 hingga Januari 2013. Pola sebaran dipetakan dengan menggunakan GPS, dan dikuantifikasikan dengan menggunakan kuadrat 1 m2, yang diletakkan pada total 12 transek untuk masing-masing lokasi. Perilaku diamati dengan menandakan 10 individu Protoreaster nodosus secara manual dan mengukur titik perpindahan selama tiga hari. Pemetaan dan analisis nilai dispersi dengan menggunakan Indeks dispersi Morisita terstandarisasi menghasilkan pola sebaran mengelompok untuk Protoreaster nodosus dan Archaster typicus, dan pola sebaran acak untuk Echinaster luzonicus, Linckia laevigata dan Linckia multifora. Sebaran mengelompok tersebut dapat disebabkan oleh batasan habitat, sebaran makanan dan atraksi intraspesifik, sedangkan sebaran acak menandakan sifat acak atau seragam pada pakan dan karakter habitat. Studi perilaku memperlihatkan bahwa P. nodosus bergerak secara direksional, dan dapat berpengaruh pada pola sebarannya di lokasi.

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Distribution pattern and behavior of intertidal asteroids in Gilimanuk Bay and Cekik Beach were investigated from September 2012 to January 2013. Distribution patterns for most species were mapped by using GPS, and quantified by using 1 m2 quadrats, which were deployed on total 12 transects in the intertidal zone at each location. Behavior was observed by using manual tagging on ten individuals of Protoreaster nodosus and measuring points of diplacement throughout a period of three days. Mapping and dispersion analysis using Morisita‟s standardized index of dispersion yielded clumped dispersion for Protoreaster nodosus and Archaster typicus, and random dispersion for Echinaster luzonicus, Linckia laevigata and Linckia multifora. Clumped dispersion in some species might be influenced by habitat boundaries, food dispersion or intraspecific attraction, while random dispersion suggests randomness or uniformity in food distribution and habitat character. Behavioral studies showed that P. nodosus moves in a highly directional manner, and might carry further implications to its clumped dispersion at location. "

"Teripang telah diketahui banyak memiliki manfaat biologis, seperti antikanker, antifungal, antivirus, dan antioksidan. Penelitian dilakukan untuk mengetahui aktivitas antioksidan dan mendeteksi keberadaan senyawa saponin pada ekstrak kasar Holothuria atra (Echinodermata) dan fraksi-fraksinya. Senyawa radikal bebas DPPH digunakan untuk pengujian aktivitas antioksidan sedangkan uji busa digunakan untuk mendeteksi keberadaan senyawa saponin. Hasil penelitian menunjukkan bahwa ekstrak kasar H. atra mengandung saponin dan memiliki aktivitas antioksidan yang lebih rendah dari pembandingnya, Acanthaster sp. (Echinodermata) dengan nilai IC50 masing-masing sebesar 739,194 μg/ml dan 102,946 μg/ml. Fraksi n-heksan, fraksi etil asetat, dan fraksi air memiliki aktivitas antioksidan yang kurang kuat dengan nilai IC50 secara berurutan 511,35 μg/ml, 373,776 μg/ml, dan 491,8 μg/ml. Uji saponin terdeteksi positif pada semua fraksi kecuali fraksi etil asetat.

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Sea cucumber had been known for having many biological uses, such as anticancer, antifungal, antivirus, and antioxidant. This study was conducted to test the antioxidant activity and to detect the presence of saponin compounds in Holorhuria atra (Echinodermata) crude extract and its fractions. Free radical compound, DPPH, was used to test the antioxidant activity and foam test was used to detect the presence of saponin compounds. The result showed that crude extract of H. atra contains saponins and has weaker antioxidant activity than Acanthaster sp. (echinoderm). The IC50 values are 739,194 μg/ml and 102,946 μg/ml, respectively. N-hexane fraction, ethyl acetate fraction, and water fraction have weak antioxidant activities with IC50 values 511,35 μg/ml, 373,776 μg/ml, and 491,8 μg/ml, respectively. Saponin test showed that all of the crude extract fractions showed positive results, except in ethyl acetate fraction."