scholarly journals STATUS OF CORAL REEFS IN THE LEMBEH STRAITS AND ADJACENT WATER, NORTH SULAWESI

2015 ◽  
Vol 37 (2) ◽  
pp. 57-61
Author(s):  
Suharsono

Lembeh reefs and its water surrounding are among the richest and most diverse in marine biota in Indonesia. The biota and reefs in this area have an important contribution to the province’s economy in the form of tourisms and fishery activities. An inventory using line intercept transect and free collection on the coral diversity has been conducted in four different locations showed that live coral cover ranging from 12.2–60.7% while sand rubble ranged from 4.67 to 78.67%. Among the life form categories, sponge dominated other biota with 0.47–21.97% coverage. Macro algae and turf algae cover were low at all sites, with average less than 2.07%. A total of 193 corals species belonging to 68 genera were recognized from this area. The differences among sites may be consequences of water quality, habitat variability and condition of the land base activities. Water turbidity in the coastal area of Kema was high due to the effects of water discharge from river mouth. Further, poor land management, development of port and human settlement leading to sedimentation, water pollution and poor water quality, remain the primary causes of reefs declines. Busy harbor and local sea transportation will be the major cause of coral reef degradation in the near future. There is a need to increase awareness of local people about the important of coral reefs and to develop management and conservation efforts involving scientists, academe and tourist operators. In addition, it is a need to strengthen the capabilities and capacities of institutions that concern reef management and enforce legislation. 

2020 ◽  
Vol 9 (2) ◽  
pp. 123-130
Author(s):  
Renanda Nur Erviana ◽  
Pujiono Wahyu Purnomo ◽  
Supriharyono Supriharyono

ABSTRAKKemujan dan Sintok merupakan pulau yang termasuk ke dalam zona pemanfaatan sebagai wisata bahari dan memiliki keanekaragaman bentuk pertumbuhan karang yang tinggi. Bentuk pertumbuhan karang dibedakan menjadi karang acropora dan non-acopora dengan perbedaan morfologi seperti tipe branching, massive, encruisting, foliose, dan digitae. Analisis morfologi karang sebagai pendukung status penutupan karang dapat mengetahui kondisi terumbu karang sesuai class conservation. Tujuan penelitian ini mengetahui kualitas perairan, struktur terumbu karang, morfologi karang berdasarkan class conservation dan pengaruh kedalaman terhadap struktur serta morfologi karang di Pulau Kemujan dan Sintok. Pengambilan data dilaksanakan pada bulan November 2019.  Metode penelitian yang digunakan adalah metode Underwater Photo Transect (UPT) dengan menggunakan transek sepanjang 30 meter. Data yang diambil adalah parameter kualitas perairan dan foto underwater karang. Data hasil penelitian diolah menggunakan aplikasi CPCe (Coral Point Count with Excel extensions) dan uji non parametrik dengan SPSS serta dianalisis menggunakan diagram r-K-S. Hasil penelitian menunjukkan bahwa kualitas perairan pada lokasi penelitian masih dalam keadaan normal. Persentase kelimpahan karang hidup termasuk dalam kategori sedang sampai dengan sangat baik yaitu  berkisar 25,56 -76,22%. Persentase morfologi karang berdasarkan Class conservation secara umum memiliki dominasi kelompok kompetitors (K) atau CC=2 yang berkisar 48,72 – 76,5%,  hal ini menunjukkan bahwa pada lokasi penelitian didominasi karang bentuk branching maupun foliose serta tidak ada pengaruh signifikan kedalaman air terhadap morfologi karang. ABSTRACTKemujan and Sintok are islands in the utilization zone as marine tourism and have high diversity of coral growth forms. The coral’s life form can be grouped into acropora and non-acopora corals with morphological differences such as branching, massive, encruisting, foliose, and digitae types. Morphological analysis of corals as supporting the status of coral cover can determine the condition of coral reefs according to class conservation. The purpose of this study are to determine the quality of the waters, the structure of coral reefs, coral morphology based on class conservation and the influence of depth on the structure and morphology of corals in Kemujan and Sintok Islands. Data collection was carried out in November 2019. The research method used was the Underwater Photo Transect (UPT) method using a 30 meter transect. The data collected the parameters of water quality and underwater coral photos. The research data were processed using the CPCe (Coral Point Count with Excel extensions) application and non-parametric tests with SPSS and analyzed using the r-K-S diagram. The results showed that the water quality at the study area was still in a normal condition. However, there was no significant effect of water depth on coral morphology. The percentage of live coral abundance was included in the moderate to very good category, ranging from 25.56 to 76.22%. Percentage of coral morphology based on Class conservation generally has a predominance of competitor groups (K) or CC = 2 ranging from 48.72 - 76.5%. Moreover, the results show that based on the coral growth forms at the study sites were dominated by branching and foliose corals and there was no significant effect of water depth on coral morphology.  


2020 ◽  
Vol 3 (1) ◽  
pp. 20-28
Author(s):  
Almaarif ◽  
Joko Samiaji ◽  
Thamrin Thamrin

Coral reefs are one of the ecosystems that have ecological functions for marine life, one of which is reef fish. Coral fish are marine biota that live in association with coral reefs. This study aims to determine the abundance of reef fish, the condition of coral reefs and the relationship between abundance of reef fish and coral reefs. This research was conducted in June 2019 in the waters of Tikus Island, Bengkulu City. The method used is a survey method. Data collection on reef fish was carried out using the Underwater Visual Census (UVC) method and coral reefs condition data colletion is done using the Line Intercept Transect (LIT) method. The abundance of reef fish found at the study site averages in the abundant category. At station I, an abundance of reef fish was 2,18 ind/m2, at station II it was 4,18 ind/m2, and at station III it was 1,27 ind/m2. While the average condition of coral reefs at the study site is include in the medium category. At station I, the percentage of live coral cover was 39,30% or include in the medium category. At station II, the percentage of live coral cover was 50,94% or include in the good category. And at station III, the percentage of live coral cover was 46,32% or include in the medium category. Coral fish and coral reefs have a fairly close relationship. Reef fish use coral reefs as a place to find food, shelter and spawn or breed.


2019 ◽  
Vol 6 (2) ◽  
pp. 45
Author(s):  
Ivone F Pakasi ◽  
Lawrence J.L Lumingas ◽  
Rene Ch Kepel ◽  
Arie B Rondonuwu

Title (Bahasa Indonesia): Tutupan karang hidup dan keanekaragaman genera karang Scleractinia di Pantai Timur Kabupaten Minahasa, Sulawesi Utara The coastal waters east of Minahasa Regency of North Sulawesi Province is one of the areas of water that have the potential to be used as Marine Protected Areas. This study provides information on the condition of coral reefs on the eastern coast of Minahasa Regency, especially in Kamenti and in Toloun. Sampling withSCUBA was conducted using lifeform categories and transects in the form of a 50 m measuring tape with 'Line Intercept Transect' techniqueat thedepthsof 5 m, 10 m and 15 m. The condition of coral reefs in the eastern coastal waters of Minahasa Regency is generally 'good'. The percentage of coral cover in Kamenti was categorized'good', while in the waters Toloun are in a state of 'average'. Genera richness on both sites can be quite high, intotal there are44 genera with 35 genera in Kamenti and 38 genera in Toloun. Kamenti station with the depth of 15 m hasthe highest conservation value because in addition to having the highest number of genera (32 genera), it has also the highest Shannon index (3.35), the highest genera richness index (8.29), the highest genera evenness index (0, 97) and the lowest dominance index (0.12). There is no apparent correlation between the percentage of live coral cover with the number of genera or the Shannon index. But the high percentage of live coral cover is not always identical with the high genera richness; the maximum genera richness is at the intermediatecover level.Perairan pantai sebelah timur Kabupaten Minahasa Provinsi Sulawesi Utara merupakan salah satu kawasan perairan yang berpotensi untuk dijadikan Kawasan Konservasi Perairan. Penelitian ini memberikan informasi tentang kondisi terumbu karang di pantai timur Kabupaten Minahasa khususnya di Kamenti dan di Toloun. Sampling dengan menggunakan SCUBA dilakukan dengan metode kategori lifeformdan menggunakan transek berupa pita meteran sepanjang 50 m dengan teknik ‘Line Intercept Transect‘  pada kedalaman 5 m, 10 m dan 15 m. Kondisi terumbu karang di perairan pantai timur Kabupaten Minahasa umumnya ‘baik’. Persentase tutupan karang batu di Kamenti berada pada kategori ‘baik’ sedangkan di perairan Toloun berada pada kondisi ‘sedang’. Kekayaan genera pada kedua lokasi penelitian dapat dikatakan cukup tinggi yakni secara total terdapat 44 genera dengan masing-masing 35 genera di Kamenti dan 38 genera di Toloun. Stasiun Kamenti kedalaman 15 m adalah yang paling tinggi nilai konservasinya karena selain memiliki jumlah genera terbanyak (32 genera), juga memiliki indeks Shannon tertinggi (3,35), indeks kekayaan genera tertinggi (8,29), indeks kemerataan genera tertinggi (0,97) dan indeks dominasi terendah (0,12). Tidak terdapat hubungan yang nyata antara persentase tutupan karang hidup dengan jumlah genera atau indeks Shannon. Tetapi persentase tutupan karang hidup yang tinggi tidak selalu indentik dengan tingginya kekayaan genera; kekayaan genera maksimun berada pada tingkat tutupan menengah.


2019 ◽  
Vol 7 (1) ◽  
pp. 186
Author(s):  
Billy N. Ompi ◽  
Unstain N.W.J. Rembet ◽  
Ari B. Rondonuwu

This research objective was to determine the condition of Coral Reef ecosystems in Dakokayu and Hogow Islands, Southeast Minahasa Regency. The method that has been used in this studies that is Line Intercept Transect (LIT) by diving activities at 5 meter and 10 meters depth with 50 meters transect length. Each biota passed by the line transect recorded according based on shape of growth.Coral Reefs conditon in Hogow Island in 5 meters and 10 meters depth were categorized as a “Good” where the percentage of live coral cover in 5 meters depth is 70.12% and in 10 meters depth  is 55.78%. The condition of Coral Reefs on Dokokayu Island at a depth of 5 meters is categorized “Good” with the percentage of live coral cover is 56.32% while in the 10 meters depth it is categorized as “Medium” with the percentage of live coral cover is 48.10%. Water quality parameters such as temperature, salinity, brightness, pH, and dissolved oxygen (DO) are within the range of tolerance for Coral Reefs to survive.Keywords: Condition, Coral Reef, Hogow, DokokayuABSTRAKTujuan penelitian untuk mengetahui kondisi ekosistem terumbu karang di Pulau Dakokayu dan Pulau Hogow, Kabupaten Minahasa Tenggara.  Metode yang telah digunakan dalam penelitian ini yaitu Line Intercept Transek (LIT) dengan melakukan penyelaman pada kedalaman 5 dan 10 meter dengan panjang transek 50 meter.  Setiap biota yang dilewati transek akan dicatat menurut bentuk pertumbuhannya. Secara umum, kondisi terumbu karang di Pulau Hogow pada kedalaman 5 meter dan 10 meter, dikategorikan Baik dimana persentasi tutupan karang hidup pada kedalaman 5 meter sebesar 70,12% dan pada kedalaman 10 meter sebesar 55,78%.  Kondisi terumbu karang di Pulau Dokokayu pada kedalaman 5 meter dikategorikan Baik  dengan persentase tutupan karang hidup 56,32% sedangkan di kedalaman 10 meter dikategorikan  Sedang  dengan persentase tutupan karang hidup 48,10 %. Parameter kualitas perairan seperti suhu, salinitas, kecerahan, pH, dan oksigen terlarut (DO) berada dalam kisaran toleransi bagi terumbu karang untuk dapat bertahan hidup.Kata Kunci : Kondisi, Terumbu Karang, Hogow, Dokokayu


Author(s):  
Robert Towoliu

In order to know the coral reef conditions at several diving points around Bunaken Island, three dive locations (Ron’s point, Lekuan, and Tawara) were chosen as representative locations receiving pressures from snorkeling and SCUBA diving activities, while  core zone was representative of location for  no diving and fishing activities.  Results showed that location with diving activities had live coral cover  ranging from 16.89% to 45.78% at 3 and 10m depths, with condition range of bad to moderate, while the location for no diving and fishing activities (core zone) had live coral cover of 55.03% at 3m and 58.15% at 10m, respectively,  with good condition category.  The present study indicated that the diving activities have affected the coral reef condition, so that a sustainable integrated management system is needed to use the marine ecotourism potency without degrading the coral reef condition in Bunaken Island. Untuk mengetahui kondisi terumbu karang di beberapa lokasi penyelaman di Pulau Bunaken, tiga lokasi penyelaman(Ron’s point, Lekuan, dan Tawara) dipilih mewakili lokasi dengan tekanan aktivitas penyelaman snorkeling maupun SCUBA, sedangkan satu lokasi lainnya yaitu zona inti dipilih mewakili lokasi tanpa aktivitas penyelaman maupun aktivitas penangkapan ikan.  Hasil penelitian ini memperlihatkan bahwa lokasi dengan tekanan aktivitas penyelaman memiliki prosentase tutupan karang batu/hidup berkisar antara 16,89% - 45,78% pada kedalaman 3 dan 10m, dengan kategori kondisi terumbu karang buruk sampai cukup, sedangkan pada lokasi yang tidak memiliki aktivitas penyelaman memiliki prosentase tutupan karang batu/hidup sebesar 53,03% pada 3m dan 58,15% pada 10m dengan kategori kondisi terumbu karang adalah baik.  Hasil penelitian ini mengindikasikan bahwa aktivitas penyelaman snorkeling maupun SCUBA berdampak pada kondisi terumbu karang di Pulau Bunaken, sehingga sangat diperlukan system pengelolaan yang terpadu dan berkesinambungan dalam memanfaatkan secara maksimal potensi ekowisata bahari tanpa merusak ekosistem terumbu karang di Pulau Bunaken.


2021 ◽  
Vol 324 ◽  
pp. 03007
Author(s):  
Ni Wayan Purnama Sari ◽  
Rikoh Manogar Siringoringo ◽  
Muhammad Abrar ◽  
Risandi Dwirama Putra ◽  
Raden Sutiadi ◽  
...  

Observations of the condition of coral reefs have been carried out in Spermonde waters from 2015 to 2018. The method used in this observation uses Underwater Photo Transect (UPT), and the data obtained is analyzed using CPCe (Coral Point Count with Excel Extensions) software. The results show that the percentage of coral cover has increased from year to year. The percentage of live coral cover in 2015 was 19.64%, 23.60 in 2016, 23.72% in 2017, and 27.83% in 2018. The increase in live coral cover from year to year is thought to occur due to the availability of nutrients. or increasing public awareness, considering this location is one of the most famous tourist attractions in Makassar. Coral reef health index values can be used to classify coral reef health. Through the analysis of the coral reef health index, an index value of 4 was obtained, which means that the condition of the coral reefs is in the “moderate” category.


2021 ◽  
Vol 8 ◽  
Author(s):  
Juan L. Torres-Pérez ◽  
Carlos E. Ramos-Scharrón ◽  
William J. Hernández ◽  
Roy A. Armstrong ◽  
Maritza Barreto-Orta ◽  
...  

Land-based sediment stress represents a threat to many coral reefs in Puerto Rico primarily as a result of unrestricted land cover/land use changes and poor best management practices. The effects of such stresses have been documented along most coasts around the island. However, little attention has been paid to reefs located on the north coast, and very little is known about their composition and current state. Here, we present a study characterizing riverine inputs, water quality conditions, and benthic composition of two previously undescribed coral reefs (Tómbolo and Machuca reefs) located just eastward of the Río Grande de Manatí outlet in north-central Puerto Rico. This study utilizes a time series of remotely sensed ocean color products [diffuse vertical attenuation coefficient at 490 nm (Kd490) and chlorophyll-a concentration (Chl-a) estimated with data from the Visible Infrared Imaging Radiometer Suite (VIIRS)] to characterize water quality in this coastal region. In general, the months with relatively high mean daily river streamflow also coincide with months having the highest proportion of eastward wave direction, which can promote the eastward influence of river waters toward the two coral reefs sites. Kd490 and Chl-a showed a higher riverine influence closer to the watershed outlet. Kd490 and Chl-a monthly peaks also coincide with river streamflow highs, particularly at those pixels closer to shore. Tómbolo Reef, located farther eastward of the river outlet, shows a well-developed primary reef framework mainly composed of threatened reef-building species (Acropora palmata, Pseudodiploria) and high coral cover (19–51%). The benthos of Machuca Reef, located closer to the river outlet, is dominated by macroalgae with a significantly lower coral cover (0.2–2.7%) mainly composed of “weedy” coral species (Porites astreoides and Siderastrea radians). Cover of major benthic components correlates with distance from the river outlet, and with gradients in Kd490 and Chl-a, with higher coral cover and lower macroalgal cover farther from the river outlet. Coral cover at Tómbolo Reef is higher than what has been reported for similar sites around Puerto Rico and other Caribbean islands showing its ecological importance, and as up until now, an unrecognized potential refuge of reef-building threatened coral species.


Author(s):  
Wei Khang Heng ◽  
Ming-Jay Ho ◽  
Chao-Yang Kuo ◽  
Ya-Yi Huang ◽  
Chia-Ying Ko ◽  
...  

Outbreak of crown-of-thorns sea stars, Acanthaster cf. solaris, were documented in coral reefs around Taiping Island, Spratlys for the first time. The outbreak might be thereason for the significant decline in live coral cover in 2021. Comprehensive monitoring through regional collaboration is needed.


Author(s):  
Joel G. Becira ◽  
Benjamin J. Gonzales ◽  
Honorio B. Pagliawan

In Palawan, Philippines, Honda Bay is fast becoming a target recreational site for curious domestic and foreign visitors. The general objectives of this resource assessment are to gather information regarding status of the marine resources in Pandan Island, and to provide recommendations for their sustainable use. Assessment was done using line intercept transect (LIT), fish visual census (FVC) and an imaginary transect belt for coral cover, fish, and macro-invertebrates, respectively. Average live coral cover around Pandan Island can be categorized as good (57%), with stations 7 and 1 and 2 categorized as excellent (76-100%) and fair (26-50%) conditions, respectively. Some 178 fish species were recorded in Pandan Island waters of which seven (7) highly target and 29 common commercial fish species were found. The estimated total reef fish biomass around Pandan Island is 588 mt/ km2. A total of eight macro invertebrate (shells, etc.) species belonging to five families was found around Pandan Island. The study concluded that of these eight species, six are commercially important,Tridacnacro cea(taklobo), Tridacnasquamosa (taklobo), Hippopusporcellanus(taklobo), Trochusniloticus(topshell), Pinna nobilis (tarab), and Bohadschiamarmota (sea cucumber). Five of these species the T. crocea, T. squamosa, H. porcellanus, P. nobilis, and T. niloticus are listed as endangered species by International Union for Conservation of Nature.   Keywords - target species, macro-invertebrates, coral cover, coral reefs, reef fish, conservation


2018 ◽  
Vol 66 (1-1) ◽  
pp. 280 ◽  
Author(s):  
Juan José Alvarado ◽  
Andrés Beita-Jiménez ◽  
Sebastián Mena ◽  
Cindy Fernández ◽  
Jorge Cortés ◽  
...  

Abstract: When conservation can keep up with development´s pace: Health status of coral ecosystems in the North Pacific of Costa Rica. Coral reefs are diverse and productive ecosystems, despite this, they are being threatened by human activities that enhance the detrimental impact of the natural phenomenon’s like Harmful Algal Blooms (HAB). The north Pacific of Costa Rica has been characterized as one of the best regions for the coral reefs development in the country. However, many of these ecosystems are being lost as a result of eutrophication, overfishing, invasive species and others impacts that affect the region. In the present study, live coral cover in the north Pacific was 5.0 ± 10.4(s.d.) %, with a domination in the ecosystems by turf algae. Twenty-six invertebrate taxa were registered in the region with the predominance of the sea urchin Diadema mexicanum. Ninety-four species of reef fish were identified. Snappers and some planktivores species were the groups with the highest frequency and abundance. The localities previously studied in the 1990 decade, presented a mean live coral cover between 40-50 %, whereby the actual state of the reef reflect a significant deterioration. This decline in coral cover is due to natural events like the El Niño, as well as the decrease in water quality in the region. In recent years, proliferations of the invasive seaweed Caulerpa sertularioides and high densities of bioerosive sea urchins have been reported, mainly associated with HAB events. Likewise, fish communities have low biomass, especially in the vicinity of fishing villages. The state of the reefs in the North Pacific is worrying and requires actions for its recovery and conservation, for which there must be better planning of the development of projects and activities on the coast. Rev. Biol. Trop. 66(Suppl. 1): S280-S308. Epub 2018 April 01. 


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