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"Coral reefs are the 'rain forests' of the ocean, containing the highest diversity of marine organisms and facing the greatest threats from humans. As shallow-water coastal habitats, they support a wide range of economically and culturally important activities, from fishing to tourism. Their accessibility makes reefs vulnerable to local threats that include over-fishing, pollution and physical damage. Reefs also face global problems, such as climate change, which may be responsible for recent widespread coral mortality and increased frequency of hurricane damage. This book, first published in 2006, summarises the state of knowledge about the status of reefs, the problems they face, and potential solutions. The topics considered range from concerns about extinction of coral reef species to economic and social issues affecting the well-being of people who depend on reefs. The result is a multi-disciplinary perspective on problems and solutions to the coral reef crisis."

"Penelitian yang bertujuan untuk menguji aktivitas antifeedant fraksi air ekstrak Capillaster sentosus telah dilakukan pada tanggal 16 sampai 22 April 2016 di perairan Pulau Pramuka, Kepulauan Seribu, DKI Jakarta. Sampel Capillaster sentosus diekstrak dengan metanol dan menghasilkan persentase ekstrak kasar sebesar 3,0%. Ekstrak selanjutnya difraksinasi dengan pelarut akuades, n-heksan dan etil asetat untuk mendapatkan fraksi air seberat 25,7 gram dengan konsentrasi fisiologis 25,4 mg/mL. Uji antifeedant dilakukan dengan menggunakan pakan perlakuan yang mengandung fraksi air ekstrak Capillaster sentosus, serta pakan tanpa fraksi air ekstrak Capillaster sentosus sebagai kontrol, dalam bentuk kubus jeli 1 cm3 yang dikaitkan pada tali pancing. Pakan tersebut kemudian diujikan pada ikan di terumbu karang dengan kedalaman 3--4 meter dan dihitung jumlah pakan yang dimakan dan tidak. Hasil uji statistik Chi-kuadrat pada taraf signifikasi (α) 0,01 menunjukkan bahwa terdapat pengaruh pemberian pakan perlakuan pada ketidaksukaan makan ikan. Berdasarkan hal tersebut maka fraksi air ekstrak Capillaster sentosus positif memiliki aktivitas antifeedant terhadap ikan karang.

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To investigate the antifeedant activity of water fraction extract of Capillaster sentosus against reef fishes, a field experiment was conducted on April, 16th to 22nd 2016 at Pramuka Island, Kepulauan Seribu, DKI Jakarta. Capillaster sentosus samples were extracted with methanol to yield crude extract of 3,0%. The extract was further fractionated with aquades, n-hexane and ethyl acetate to obtain 25,7 gram water fraction of which the physiological concentration is 25,4 mg/mL. The antifeedant assay was conducted by using artificial foods that contained the water fraction of Capillaster sentosus’s extract and the control food, of each in 1 cm3 jelly cubes that were tieded to fishing lines. The foods were subjected to coral reefs fishes at depth of 3--4 m and the amount of food eaten and not eaten by reef fishes was recorded. Chi-square analysis (α= 0,01) revealed that there is treatment effect on the feeding preferences of reef fishes. This means that the water fraction of Capillaster sentosus’s extract has an antifeedant activity against reef fishes."

"Penelitian ekperimental untuk menguji aktifitas antifeedant ekstrak metanol Archaster typicus terhadap ikan karang telah dilakukan di Perairan Pulau Pramuka, Kepulauan Seribu, DKI Jakarta. Sampel diekstrak dengan metode maserasi dengan menggunakan pelarut metanol. Uji antifeedant dilakukan dengan mengaitkan pakan buatan yang mengandung ekstrak metanol Archaster typicus pada konsentrasi fisiologis (0,0245 g/ml), jeli, makanan ikan, dan pewarna makanan menggunakan peniti pada tali propilen. Pakan tersebut kemudian diuji di terumbu buatan pada kedalaman 3 m dan diamati jumlah pakan yang dimakan dan tidak oleh ikan karang. Analisis chi kuadrat pada tingkat kepercayaan 0,01 menunjukkan bahwa terdapat korelasi antara dimakan dan tidak dimakannya pakan perlakuan terhadap penambahan ekstrak metanol Archaster typicus. Penelitian menunjukkan ekstrak metanol Archaster typicus positif memiliki aktivitas antifeedant terhadap ikan karang dan hal tersebut diduga disebabkan oleh adanya kandungan saponin pada ekstrak metanol Archaster typicus.

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To investigate antifeedant activity of methanol extract of Archaster typicus against reef fishes a field experiment was conducted at Pramuka Island Watery, Seribu Island, DKI Jakarta. Archaster typicus samples were extracted using maceration method while taking methanol as the solvent. The antifeedant assay was conducted by attaching the artificial food that contains methanol extract of Archaster typicus at natural concentration (0.0245 g/ml), jelly, fish food, and food dye, using safety pins to propylene ropes. After that, the artificial food was observed at artificial reef in 3 m depth. The amount of artificial food eaten and left by reef fishes was also observed. Chi square analysis for α (p) = 0.01 revealed that there is correlation between eaten and not eaten of treat food to addition of methanol extract of Archaster typicus. That means methanol extract of Archaster typicus has antifeedant activity againts reef fishes. That was beyond saponin content in the extract."

"Terumbu karang memiliki manfaat ekologis, ekonomis, dan sosial budaya yang signifikan sebagai komponen habitat bentik di perairan dangkal. Tujuan dari penelitian ini adalah untuk mengategorikan persebaran habitat bentik secara spasial dan temporal tahun 2017-2023 dan bagaimana hubungan antara perubahan luas karang dengan kualitas perairan di Pulau Satonda pada tahun 2017–2023. Kualitas perairan yang digunakan dalam penelitian ini berupa suhu permukaan laut (SST), klorofil-a, dissolved oxygen (DO), salinitas, dan turbiditas. Citra satelit digunakan karena mampu memantau dalam cakupan luas dan jangka waktu yang panjang. Penelitian dilakukan di Pulau Satonda karena kawasan konservasi laut yang masih minim publikasi ilmiah mengenai habitat bentik/kondisi terumbu karang. Penelitian ini menggunakan data primer dari survei Underwater Photo Transect (UPT) dan data sekunder berupa citra PlanetScope thun 2017-2023, data habitat bentik yang sudah diklasifikasi, dan data kualitas air. Citra PlanetScope diolah menggunakan metode Object-Based Image Analysis (OBIA) dengan algoritma segmentasi Simple Non-Iterative Clustering (SNIC) dan algoritma klasifikasi Random Forest (RF). Sebanyak 1.365 titik habitat bentik dibagi menjadi data training dan validation, serta uji akurasi menggunakan confusion matrix. Analisis spasial dilakukan melalui overlay peta karang dan kualitas air serta analisis temporal menggunakan grafik deret waktu. Model klasifikasi memiliki nilai overall accuracy (OA) sebesar 62,84% (Kappa = 0,50). Mayoritas habitat bentik adalah karang dan pecahan karang. Parameter kualitas air masih dalam nilai ambang batas. Namun, nilai SST sedikit melebihi ambang batas dan salinitas berada di bawah ambang batas. Kondisi ini diduga berhubungan dengan penurunan luas karang.

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Coral reefs have significant ecological, economic, and socio-cultural benefits as benthic habitat components in shallow waters. This study aims to categorize the spatial and temporal distribution of benthic habitat in 2017-2023 and how the relationship between coral area changes and water quality in Satonda Island in 2017-2023. Water quality variables include sea surface temperature (SST), chlorophyll-a, dissolved oxygen (DO), salinity, and turbidity. Satellite imagery was used because it is capable of wide area and long time period monitoring. Satonda Island was chosed because it is a marine conservation area with limited scientific publications on benthic/coral reef condition. The primary data from the Underwater Photo Transect (UPT) survey and secondary data in the form of PlanetScope images from 2017-2023, classified benthic habitat data, and water quality data. PlanetScope images were processed using the Object-Based Image Analysis (OBIA) method with the Simple Non-Iterative Clustering (SNIC) segmentation algorithm and the Random Forest (RF) classification algorithm. A total of 1,365 benthic habitat points were divided into training and validation data, and accuracy was tested using confusion matrix. Spatial analysis was conducted through overlaying coral and water quality maps and temporal analysis using time series graphs. The classification model had an overall accuracy (OA) of 62.84% (Kappa = 0.50). The majority of benthic habitats were corals and rubbles. Water quality parameters are still within the threshold value. However, SST values slightly exceeded the threshold and salinity was below the threshold. This condition is thought to be associated with a decrease in coral area."

"ABSTRACTOceans cover 70 percent of the Earth surface. Coastal and shallow water areas contain the most productive and diverse ecosystem, including coral reefs, mangroves and sea grass beds. Coral reefs, as referred to the tropical rainforest of the ocean, is a marine system whose valued about 30 million USD per year: Coral protects shares and islands from the strong waves and surges. Along with sea grass beds and mangroves, coral reefs acts as the biggest carbon sink from atmosphere in the earth. The tropical coral reefs worldwide cover an area of 284. 000 km2 can absorb carbon as much as 4 milion tons carbondioxide every year: It is five times higher than tropical rain forests can absorb. It is why people called it as blue carbon. On the other hand, some people say that coral reef is also acts as the carbon source."

"Summary:Providing a guide for marine conservation practice, Marine Conservation takes a whole-systems approach, covering major advances in marine ecosystem understanding. Its premise is that conservation must be informed by the natural histories of organisms together with the hierarchy of scale-related linkages and ecosystem processes"