BAKTERI ASOSIASI PADA KARANG SCLERACTINIA KAITANNYA DENGAN FENOMENA LA-NINA DI PULAU BUNAKEN

Penelitian tentang karang keras (Scleractinian coral) yang terkontaminasi bakteri relatif masih kurang dilakukan khususnya di perairan Indonesia. Untuk itu dilakukan kegiatan penelitian di Taman Nasional Bunaken pada dua periode yakni Mei 2010 (musim peralihan I)  dan Agustus 2011 (Monsoon II). Penelitian ini difokuskan pada kontaminasi bakteri gram positif (+) dan gram negatif (-). Metode yang dilakukan untuk pengambilan sampel di lapangan adalah time swim dimana menyelam  pada kedalaman 5-10 meter selama kurang lebih 30 menit dan mengambil sampel mucus karang secara acak/random dengan menggunakan siring atau mengambil sampel secara langsung pada karang (fraksi cabang) pada lokasi yang sama. Sampel dianalisis dengan proses isolasi bakteri di laboratorium. Hasil penelitian menunjukkan bahwa pada  Mei 2010 bakteri gram positif lebih mendominasi dari gram negatif, sebaliknya Agustus 2011 bakteri gram negatif yang lebih dominan dari gram positif.  Indikasi faktor penyebab terjadinya bakteri gram positif yang lebih dominan khususnya di tahun 2010  ialah fenomena La-Nina yang terjadi selama periode tersebut. Perubahan suhu rata-rata yang terjadi pada kedua musim tersebut menjadi salah satu faktor yang merangsang pertumbuhan kedua kelompok bakteri ini.  Perlu dilakukan penelitian lebih lanjut khususnya dalam menentukan jenis bakterinya dan pengambilan sampel pada setiap musim

PEMETAAN HABITAT BENTIK PADA EKOSISTEM TERUMBU KARANG DI PERAIRAN PULAU MENJANGAN

Ekosistem pesisir yang meliputi tiga bagian penting yakni mangrove, padang lamun dan terumbu karang merupakan bagian yang tidak terpisahkan dalam proses pemetaan habitat. Penelitian ini bertujuan untuk melakukan pemetaan habitat secara geomorfologi di Pulau Menjangan, Taman Nasional Bali Barat, Bali. Pengumpulan data lapangan dilakukan pada bulan Februari, April dan Agustus 2017.  Total 104 titik sampling telah dikumpulkan, dan dilakukan analisis perbedaan tekstur menggunakan program ENVI v4.7 dari data citra satelit  Worldview 2 dengan resolusi spasial 2 m, tanggal 14 Oktober 2016. Hasil penelitian menunjukkan bahwa secara geomorfologi, kawasan pesisir Pulau Menjangan terbagi dalam 6 tipe habitat yakni mangrove, terumbu depan, lereng terumbu, rataan terumbu, pecahan karang (rubble), pasir dan teras. Berdasarkan hasil foto transek habitat dengan pendekatan skala medium (Medium Scale Approach) khususnya pada daerah rataan terumbu dan terumbu depan (fore reef/crest) dapat diklasifikasikan dalam 12 jenis habitat dengan komposisi bentik dominan karang  adalah 30% yang meliputi beberapa jenis karang keras (Scleractinia) yakni Acropora sp, Montipora sp, Porites lutea dan Porites cylindrica; Rubble & Alga (dari divisi Chlorophyta dan Phaeophyta) masing-masing sebesar 16 %; Pasir  12%; Lamun (diantaranya Syringodium sp, Cymodocea sp dan Thalasia sp) 11% dan sisanya adalah asosiasi karang Heliopora coerulea (non Scleractinia), karang mati dan teras. Daerah rataan terumbu memiliki kategori rugosity berada pada level 1 - 2, sedangkan  terumbu depan dengan rugosity level 3 - 4

Characterization of the resilience of reef benthic communities by analysis of high resolution multi-source images : the case of Bunaken National Park, Indonesia

Le projet INDESO (Développement de l'océanographie spatiale en Indonésie) en collaboration entre le gouvernement indonésien (Ministère des affaires maritimes et des pêches - MMAF) et la société française CLS (Collecte Localisation Satellite) promeut l'utilisation des technologies spatiales pour la surveillance des côtes et des mers indonésiennes. Cette thèse fait partie du volet sur la surveillance des récifs coralliens, mené par l'IRD (Institut de Recherche pour le Développement). L'objectif principal était de déterminer si les habitats des récifs coralliens dans l'île de Bunaken dans le nord de Sulawesi sont résilients, en utilisant i) des cartes d'habitat nouvellement conçues, ii) des données in situ et une série chronologique de 15 ans unique d'images satellites de différents capteurs très haute résolution (THR), iii) des données auxiliaires qui pourraient expliquer les changements détectés. Les résultats comprennent des cartes très détaillées de l'habitat des récifs de Bunaken (194 polygones cartographiés et un recensement de 175 habitats). L'influence de la chute du niveau de la mer sur la mortalité des coraux pendant l'événement El Niño de 2015-2016 est présentée en détail, et l'importance de ce processus est également discutée à partir de l'interprétation d'une série chronologique unique de 15 ans d'images THR. La série temporelle met en évidence des trajectoires très différentes des habitats coralliens. Nous avons conclu que le récif de Bunaken démontre une capacité de résilience et sans déphasage, mais qu'un diagnostic définitif de sa résilience reste difficile à déterminer par imagerie. Des trajectoires de l'habitat ne peuvent pas être totalement interprétées sans changer certains paradigmes de surveillance, et sans utiliser une combinaison d'observations de télédétection et de données in situ.The INDESO (Infrastructure Development of Space Oceanography) project, in collaboration with the Indonesian Government (Ministry of Marine Affairs and Fisheries - MMAF) and the French company CLS (Collecte Localisation Satellites), promotes the use of space technologies for monitoring coastlines and Indonesian seas. This thesis is part of coral reef monitoring component, led by the IRD (Institute de Recherche pour le Développement). The main objective was to determine wether coral reef habitats on Bunaken Island in Northern Sulawesi are resilient, using (i) newly desgined habitat maps, (ii) in situ data, and a unique 15-year time series of satellite images of different very high resolution (VHR) sensors, and (iii) ancillary data that could explain the changes detected. The results include highly detailed maps of the Bunaken reefs habitat (194 polygons mapped and a census of 175 habitats). The influence of sea level fall on coral mortality during the El-Nino event of 2015 - 2016 is presented in detail, and the importance of this process is also discussed from the interpretation of a unique time series of 15 years of VHR images. The temporal series reveals very different trajectories of the coral habitats. We conclude that Bunaken reefs demonstrate an ability to resileince and without phase shift, but that a definitive diagnosis of their resilience remains difficult to determine by imagery. Habitat trajectories can not be fully interpreted without changing some monitoring paradigms and without using a combination of remote sensing and in situ data

Caractérisation de la résilience des communautés benthiques récifales par analyse d'images à très haute résolution multi-sources: le cas du Parc National de Bunaken, Indonésie

The INDESO (Infrastructure Development of Space Oceanography) project, in collaboration with the Indonesian Government (Ministry of Marine Affairs and Fisheries – MMAF) and the French company CLS (Collecte Localisation Satellites), promotes the use of space technologies for monitoring coastlines and Indonesian seas. This thesis is part of coral reef monitoring component, led by the IRD (Institute de Recherche pour le Développement). The main objective was to determine wether coral reef habitats on Bunaken Island in Northern Sulawesi are resilient, using (i) newly desgined habitat maps, (ii) in situ data, and a unique 15-year time series of satellite images of different very high resolution (VHR) sensors, and (iii) ancillary data that could explain the changes detected. The results include highly detailed maps of the Bunaken reefs habitat (194 polygons mapped and a census of 175 habitats). The influence of sea level fall on coral mortality during the El-Nino event of 2015 – 2016 is presented in detail, and the importance of this process is also discussed from the interpretation of a unique time series of 15 years of VHR images. The temporal series reveals very different trajectories of the coral habitats. We conclude that Bunaken reefs demonstrate an ability to resileince and without phase shift, but that a definitive diagnosis of their resilience remains difficult to determine by imagery. Habitat trajectories can not be fully interpreted without changing some monitoring paradigms and without using a combination of remote sensing and in situ data.Le projet INDESO (Développement de l’océanographie spatiale en Indonésie) en collaboration entre le gouvernement indonésien (Ministère des affaires maritimes et des pêches - MMAF) et la société française CLS (Collecte Localisation Satellite) promeut l’utilisation des technologies spatiales pour la surveillance des côtes et des mers indonésiennes. Cette thèse fait partie du volet sur la surveillance des récifs coralliens, mené par l’IRD (Institut de Recherche pour le Développement). L’objectif principal était de déterminer si les habitats des récifs coralliens dans l’île de Bunaken dans le nord de Sulawesi sont résilients, en utilisant i) des cartes d’habitat nouvellement conçues, ii) des données in situ et une série chronologique de 15 ans unique d’images satellites de différents capteurs très haute résolution (THR), iii) des données auxiliaires qui pourraient expliquer les changements détectés. Les résultats comprennent des cartes très détaillées de l’habitat des récifs de Bunaken (194 polygones cartographiés et un recensement de 175 habitats). L’influence de la chute du niveau de la mer sur la mortalité des coraux pendant l’événement El Niño de 2015-2016 est présentée en détail, et l’importance de ce processus est également discutée à partir de l’interprétation d’une série chronologique unique de 15 ans d’images THR. La série temporelle met en évidence des trajectoires très différentes des habitats coralliens. Nous avons conclu que le récif de Bunaken démontre une capacité de résilience et sans déphasage, mais qu’un diagnostic définitif de sa résilience reste difficile à déterminer par imagerie. Des trajectoires de l’habitat ne peuvent pas être totalement interprétées sans changer certains paradigmes de surveillance, et sans utiliser une combinaison d’observations de télédétection et de données in situ

Seaweed farming collapse and fast changing socio-ecosystems exacerbated by tourism and natural hazards in Indonesia: A view from space and from the households of Nusa Lembongan island.

The culture of seaweed for the food and cosmetics industry is central to many rural households in Indonesia. The activity has vastly expanded in the past three decades, but in some cases, an opposite trend is now emerging. Spaceborne images were used to monitor the recent collapse of seaweed farming around the small island of Nusa Lembongan, Bali, Indonesia. A simple semi-quantitative Seaweed Farming Index highlighted the different dynamics for four different sectors around the island, with abrupt or gradual changes starting in 2012. By 2017, seaweed farming had eventually vanished from the island, after sustaining local livelihoods for more than 30 years and influencing the zoning plan of the local Marine Conservation Area since 2010. Interviews of 50 exfarmers in 2018 identified the reasons of the changes: failed crop, low selling prices, shrinking space to dry algae against coastal development, and easy alternative jobs in tourism, although not necessarily providing better salary incomes. Tourism attracted half of these farmers, while another 25% went into building construction, itself largely driven by tourism development. The vulnerability of a complete shift to tourism was highlighted when tourism temporarily collapsed for several months due to threat of a Bali volcano eruption in late 2017. This prompted ex-farmers to consider returning to farming. This integrated case study based on remote sensing and household surveys highlights the fast-changing dynamics of Indonesia coastal socio-ecosystem due to largely to tourism development and natural hazards. The consequences for local management are discussed

BAKTERI PADA KARANG SCLERACTINIA DI KAWASAN PERAIRAN BUNAKEN, MOROTAI DAN RAJA AMPAT

Research on hard coral (Scleractinian coral) contaminated with bacteria is still not much done, especially in Indonesian waters. This study took samples of coral mucus in 2010 at 3 (three) different locations, namely Bunaken (May); Morotai (September) and Raja Ampat (November), which focused on the analysis of Research on hard coral (Scleractinian coral) contaminated with bacteria is still not much done, especially in Indonesian waters. This study took samples of coral mucus in 2010 at 3 (three) different locations, namely Bunaken (May); Morotai (September) and Raja Ampat (November), which focused on the analysis of gram-positive and gram-negative bacteria. The method used for field sampling is time swim, which is by diving at a depth of 5-10 meters for ± 30 minutes and randomly taking samples of coral mucus using siring or by taking directly on corals (reef branching). Mucus samples were analyzed by bacterial isolation in the laboratory. The result shows that there were differences between gram-positive and gram-negative bacteria in the three research sites and that gram-positive bacteria were higher or dominant. Further research that can identify the bacteria species and explain its relationship to the ecosystem is highly recommended.Keywords: Bacteria, Scleractinian coral, gram-positive and -negative, Bunaken, Morotai, Raja Ampat                                               AbstrakPenelitian tentang karang keras (Scleractinian coral) yang terkontaminasi bakteri masih belum banyak dilakukan, terutama di perairan Indonesia. Penelitian ini mengambil sampel mucus karang pada tahun 2010 di 3 (tiga) lokasi berbeda, yakni Bunaken (Mei); Morotai (September) dan Raja Ampat (November), yang difokuskan pada analisis bakteri gram postif dan gram negatif. Metode yang digunakan untuk pengambilan sampel di lapangan adalah time swim, yaitu dengan penyelaman pada kedalaman 5-10 meter selama ±30 menit dan mengambil sampel mucus karang secara acak menggunakan siring atau dengan mengambil langsung pada karang (fraksi cabang). Sampel mucus dianalisis dengan cara isolasi bakteri di laboratorium. Hasil analisis menunjukkan bahwa ada perbedaan antara bakteri gram positif dan gram negative di tiga lokasi survei dan bakteri gram positif lebih tinggi atau dominan. Penelitian lebih lanjut yang dapat menentukan jenis bakteri serta menjelaskan hubungannya dengan ekosistem sangat disarankan untuk dilakukan.Kata Kunci : Bakteri, Scleractinian coral, gram positif dan negatif, Bunaken, Morotai, Raja Ampa

Ecological condition of seagrass meadow in Lembeh Island, Bitung Regency, North Sulawesi, Indonesia

The condition of seagrass meadows is required information for conducting comprehensive management plans in coastal areas. This study provides information on the ecological condition of the seagrass ecosystem in Lembeh Island, based on seagrass species richness and coverage, macroalgal coverage, epiphyte coverage, and water transparency. We collected the data by performing 24 line transects at eight stations across the island. The seagrass ecosystem condition was determined using the Seagrass Ecological Quality Index (SEQI, range 0-1). We recorded eight seagrass species in the study site, with coverage of 48.88 ± 12.35% (mean ± SE). Enhalus acoroides and Thalassia hemprichii were the most common species in the sampling stations. The coverage of macroalgal and epiphyte was substantially low, indicated by values of 1.64 ± 0.41% and 12.64 ± 3.57%, respectively. Our analysis showed that most of the seagrass meadows in Lembeh Island are in poor condition (SEQI mean: 0.48 ± 0.03), especially in the locations inside Lembeh Strait. Moderate conditions were only found outside Lembeh Strait, such as in Pancuran, Limangu, and Pasir Panjang (SEQI values: 0.60, 0.58, and 0.56, respectively). We suggest a long-term seagrass monitoring program to evaluate the trend of condition, a restoration program, and improve water environment quality

Shallow-Water Benthic Identification Using Multispectral Satellite Imagery: Investigation on the Effects of Improving Noise Correction Method and Spectral Cover

Lyzenga’s method is used widely for radiative transfer analysis because of its simplicity of application to cases of shallow-water coral reef ecosystems with limited information of water properties. WorldView-2 imagery has been used previously to study bottom-type identification in shallow-water coral reef habitats. However, this is the first time WorldView-2 imagery has been applied to bottom-type identification using Lyzenga’s method. This research applied both of Lyzenga’s methods: the original from 1981 and the one from 2006 with improved noise correction that uses the near-infrared (NIR) band. The objectives of this study are to examine whether the utilization of NIR bands in the correction of atmospheric and sea-surface scattering improves the accuracy of bottom classification, and whether increasing the number of visible bands also improves accuracy. Firstly, it has been determined that the improved 2006 correction method, which uses NIR bands, is only more accurate than the original 1981 correction method in the case of three visible bands. When applying six bands, the accuracy of the 1981 correction method is better than that of the 2006 correction method. Secondly, the increased number of visible bands, when applied to Lyzenga’s empirical radiative transfer model, improves the accuracy of bottom classification significantly

Sea bunnies as a potential marine ecotourism in sumberkima, Buleleng Regency, Bali

The Sumberkima Village has a vital coral reef ecosystem since the ecosystem has become home to some incredible marine biotas, including sea bunnies, a sea slug or Nudibranch species. The Nudibranch community can indicate the health of the ecosystem from its diversity and structure. This study aims to determine the distribution and value of the Nudibranchia Ecological Index and provide an example informative infographic of sea bunnies to support marine ecotourism at Sumberkima Village, Gerokgak District, Buleleng Regency, Bali Province. The research method applied is observation by visual census with an underwater camera (underwater visual census) and SCUBA diving equipment at a depth range of 5-25 meters. Observation data were collected in April 2021. A total of 15 species were found at ten dive sites.: Chromodoris annae, Chromodoris magnifica, Goniobranchus reticulatus, Hypselodoris apolegma, Hypselodoris bullockii, Nembrotha cristata, Nembrotha kubaryana, Nembrotha sp, Notodoris serenae, Phyllidia elegans, Phyllidia varicosa, Phyllidiopsis pipecki, Phyllidiopsis shireenae. The most dominant species was a member of Phyllidia genus, and an uncommon species is Goniobranchus reticulatus