scholarly journals Spatial analysis of coral reefs and its degradation patterns in Bunaken National Park

2019 ◽  
Vol 76 ◽  
pp. 01001
Author(s):  
Nafil Rabbani Attamimi ◽  
Ratna Saraswati
Keyword(s):  
Coral Reefs ◽  
Spatial Pattern ◽  
Shallow Water ◽  
National Park ◽  
Sea Water ◽  
Satellite Image ◽  
Landsat 8 ◽  
Marine Habitats ◽  
Observation Process ◽  
Healthy Coral

This article will analyze the spatial pattern as well as the degradation pattern of the coral reefs in the Bunaken National Park. Bunaken National Park is a marine national park located in the Province of North Sulawesi; the park was built as means of conservation as well as providing a region for tourism. The national park contains a different type of marine and land ecosystem, one of the many types of the ecosystem that are in the national park is coral reefs. Coral reefs in Bunaken National Park provides different kinds of function and benefits whether for the marine habitats that live around the ecosystem, as well as for the local people who live in the islands of the national park. Remote sensing could be used as a tool to identify the spatial pattern and the type of ecosystem that habits inside shallow sea water. The main issue with this method is that the research cannot be conduct directly to identify which type of ecosystem specifically (such as coral reefs, seagrass, etc.), as well as its condition. Therefore, data collecting is necessary to observe and identify the ecosystem and its condition specifically. This study uses satellite image from Landsat 8 OLI as the main secondary data to be processed. The satellite image will be processed by using an algorithm of shallow water analysis that was introduced by Lyzenga in 1981. Since data verification and data observation is needed for this study, the research observes the pattern of the different type of ecosystem and its condition that spreads around Bunaken National Park. The verification and observation process was done by GPS, there were 250 different samples from the data that were collected around the Bunaken National Park. The sample that was collected in the study area will be used to classify the satellite image that has been processed by shallow water algorithm, on which could identify: seagrass, bleached coral reefs, deceased coral reefs, and healthy coral reefs around the national park. The results of this study show the spatial pattern of the coral reefs is located usually around the islands in the Bunaken National Park. The results show that the coral reefs are mostly located around the islands in the National Park. The map results show that the healthy coral reefs are usually located in the outermost layer around the shallow water ecosystem. The bleached reefs are usually located in the middle section of the shallow water, between the healthy coral and the islands itself. Most of the reefs that died and bleached are in the southwest of Bunaken Island, and the northwest of Nain Island.

scholarly journals Coral Reef and Shallow Water Benthic Identification Using Landsat 7 ETM+ Satellite Data in Nusa Penida District

2018 ◽  
Vol 2 (1) ◽  
pp. 17
Author(s):  
Arief Reza Fahlevi ◽  
Takahiro Osawa ◽  
I Wayan Arthana
Keyword(s):  
Coral Reefs ◽  
Shallow Water ◽  
Health Monitoring ◽  
Confusion Matrix ◽  
Satellite Image ◽  
Kappa Coefficient ◽  
Landsat 7 ◽  
Triangle Center ◽  
Reef Health

This study aims to investigate the feasibility of Landsat 7 ETM+ to identify coral reefs and shallow water benthic at Nusa Penida district in 2009 and 2012, comparison with the Reef Health Monitoring (RHM) results conducted by the Coral Triangle Center (CTC)  using the Point Intercept Transect (PIT) method in the same periods. This study also aims to determine the changes of coral reefs and shallow water benthic cover during this period and the distribution at Nusa Penida districk. Shallow water benthic classification refers to English et al. (1997), with a modified by the addition of vegetation classes (seagrass and seaweed). The classification result using confusion matrix between the Reef Health Monitoring (RHM) with the classification of satellite image in 2009 obtained an accuracy rate of 65.85% with a kappa coefficient value of 0.525, while in 2012 the accuracy value obtained of 74.81% with kappa coefficient value of 0.650, which shows the results of that classification of satellite images of Landsat 7 ETM+ with the results of in-situ research is in a moderate level.

scholarly journals STATUS AND TRENDS OF CHANGE IN DISTRIBUTION OF MARINE HABITATS IN NHA TRANG BAY

2018 ◽  
Vol 17 (4) ◽  
pp. 469-479
Author(s):  
Nguyen Van Long ◽  
Tong Phuoc Hoang Son
Keyword(s):  
Remote Sensing ◽  
Coral Reefs ◽  
Aerial Images ◽  
Landsat 8 ◽  
Seagrass Beds ◽  
Marine Habitats ◽  
Status And Trends ◽  
Nha Trang Bay ◽  
Key Sites ◽  
Ground Truthing

Assessments of status and temporal changes in distribution of marine habitats in Nha Trang bay were conducted by using interpretation of remote sensing (Orbview 3, SPOT5, ALOS-AVNIR2 and Landsat 8-LCM) and aerial images in combination with ground truthing at 50 key sites representing coral reefs (25 sites), seagrass beds (10 sites), mangroves (5 sites), rocks (5 sites) and sand (5 sites) in 2015. A total of 812 ha of key marine habitats was recorded in 2015 including 754.1 ha of coral reefs, 52.4 ha of seagrass beds and 5.4 ha of mangroves. There was a notable decline in areas of the above marine habitats in the period of 2002 - 2015, in which 64 ha of seagrass beds (equivalent to 45%; mainly at Bai Tien, Phu Quy, Mui Nam and Vung Me, Đam Gia, Song Lo) and 117.4 ha of coral reefs (equivalent to 13.5%; mainly at Dam Gia, Duong De, Song Lo, Bai Tien and Eo Co) have been lost with an exception of increase of 3.1 ha of mangroves by new transplantation project conducted by Nha Trang MPA authority in Dam Bay during the last few years. The decline in the areas of coral reefs and seagrass beds has been caused by expansion and reclaimation of infrastructure for community and tourism development in recent years.

scholarly journals Research Bathymetry Mapping of Shallow Water Areas around Islands in the Truong Sa Archipelago by Deep - Remote sensing technology

2017 ◽  
Vol 33 (4) ◽  
Author(s):  
Phan Quoc Yen ◽  
Dao Khanh Hoai ◽  
Dinh Thi Bao Hoa
Keyword(s):  
Remote Sensing ◽  
Shallow Water ◽  
Satellite Image ◽  
Image Data ◽  
Landsat 8 ◽  
Military Operations ◽  
Sensing Technology ◽  
Remote Sensing Techniques ◽  
Map Data ◽  
The Military

Satellite image data is being researched and applied effectively in the survey and establishment of bathymetry mapping in shallow water areas in both time and human terms. Remote sensing techniques contribute to rapid updating of topography, timely assurance of civil and military operations such as maritime safety, environmental security and rescue, Warfare in the military, especially the ability to remotely monitor disputed areas. The article experiment with the Stumpf et al algorithm to estimate the shallow water depths on the Spratly Island by Landsat 8 image. The correlation coefficient of the model R2 is 0.924; RMSE is 0.99m. In addition, the results are compared with the map data of C-map and use 12 actual test points scores to evaluate the accuracy of the model.

scholarly journals Abordagem radiométrica/espectral na identificação de recifes de corais por meio de sensor orbital

2018 ◽  
Vol 40 ◽  
pp. 29
Author(s):  
Vagner Figueiredo dos Santos ◽  
Pablo Santana Santos ◽  
Ruy Kenji Papa de Kikuchi ◽  
Danilo Heitor Caires Tinoco Bisneto Melo
Keyword(s):  
Coral Reefs ◽  
Near Infrared ◽  
Sea Water ◽  
Visible Region ◽  
Infrared Region ◽  
P Value ◽  
Landsat 8 ◽  
Significance Level ◽  
Spectral Bands ◽  
Significant Difference

In Brazil, the coral reefs are distributed for practically the whole tropical coast. The urbanization of coastal regions and changes of the climate in global scale can occasion negative impacts on this ecosystem, where the identification of the coral reefs from remote sensing is an important initiative to facilitate the management of these areas.  This paper proposes a radiometric/spectral evaluation of three banks in the Complex Coral Reefs of the Abrolhos-BA (Viçosa, Coroa Vermelha and Sebastião Gomes), through graphic sensitivity and Optimum Index Factor (OIF), in satellite images OLI/Landsat-8. The sensitivity of the three banks in coral reefs was similar. The spectral bands B1, B2, B3, B4 showed sensitivity to enhance the coral reef, the sea water, and from the near-infrared region (≥B5) there was no any sensitivity, even for some emerged coral reefs, as demonstrated statistical Test-t (Student), where there was no difference statistics between the digital values of coral reefs and sea water, since the p-Value was greater than the significance level (alpha = 0.05). Of the four spectral bands in the visible region (B1, B2, B3 and B4), only the B1 presented no significant difference. According to OIF the best color composition for visual differentiation of sea water of coral reefs was 1R 2G 4B (5403.3).

scholarly journals Mapping biomass and carbon stock of forest by remote sensing and GIS technology at Bach Ma National Park, Thua Thien Hue province

2017 ◽  
Vol 8 (2) ◽  
pp. 80-87
Author(s):  
Hoang Khanh Linh Nguyen ◽  
Bich Ngoc Nguyen
Keyword(s):  
National Park ◽  
Carbon Stock ◽  
Satellite Image ◽  
Landsat 8 ◽  
Total Biomass ◽  
Adaptation To Climate Change ◽  
Gis Technology ◽  
Commercial Market ◽  
The Status ◽  
The Rich

The objective of this study is to build biomass and carbon stock map at several type of forest in Bach Ma National Park, Thua Thien Hue province. To accomplish that goal, field survey was accompanied with the interpretation result of remote satellite imagery in the GIS to determine biomass and carbon stock accumulation of forest. Landsat 8 satellite image year 2014 at 15 meters resolution was used for the analysis and classification of forest status. The results showed that the rich forest had the biggest amount biomass reserve in comparison with medium and restoration forest. It indicated that estimated biomass of rich forest was 144.16 tons/ha; meanwhile, biomass of medium and res- toration forest was reached at 43.17 tons/ha and 20.31 tons/ha, respectively. It means that the total biomass of rich forest was approximately three times as the total biomass of medium forest and seven times compared to restoration forest. Based on estimated biomass map, carbon stock map at Bach Ma National Park was calculated. The carbon stock reserve of differential forest types was unequal and considerable disparity between the rich forest and the rest. Carbon stock of rich forest was 264.53 tons/ha, which was higher nearly three times than medium forest and nearly seven times than restoration forest. The determination of biomass and carbon stock map from tree layer not only contributes to understand the status of forest conditions, but also provide a strategy in reducing emissions and adaptation to climate change. In addition, the research results could be the scientific reference for trade sell carbon certificates in the commercial market within the country and globally. Mục tiêu của nghiên cứu này là xây dựng được bản đồ sinh khối và trữ lượng cacbon của tầng cây gỗ tại một số trạng thái rừng thuộc vườn quốc gia Bạch Mã, tỉnh Thừa Thiên Huế. Để thực hiện được mục tiêu đó, nghiên cứu đã phối hợp kết quả phân loại ảnh với số liệu điều tra thực địa trong GIS để xác định sinh khối rừng, trữ lượng carbon tích lũy của tầng cây gỗ ở các trạng thái rừng thuộc vườn quốc gia Bạch Mã, tỉnh Thừa Thiên Huế. Ảnh vệ tinh landsat 8 năm 2014 có độ phân giải 15 mét được sử dụng để phân tích và phân loại hiện trạng rừng. Kết quả nghiên cứu cho thấy, trạng thái rừng giàu có sinh khối lớn hơn nhiều so với 2 trạng thái rừng còn lại, tổng sinh khối ước tính là144,16 tấn/ha. Sinh khối rừng trung bình đạt 43,17 tấn/ha, còn sinh khối rừng của rừng phục hồi là 20,31 tấn/ha. Tổng sinh khối rừng giàu xấp xỉ gấp 3 lần so với rừng trung bình và gấp 7 lần so với rừng phục hồi. Đối với trữ lượng carbon của các trạng thái rừng không đồng đều nhau và có sự chênh lệch khá lớn giữa rừng giàu và các trạng rừng còn lại. Trữ lượng carbon của rừng giàu là 264,53 tấn/ha cao hơn gần gấp 3 so với rừng trung bình và gấp gần 7 lần so với rừng phục hồi. Kết quả việc xác định sinh khối và trữ lượng carbon tầng cây gỗ của các trạng thái rừng cung cấp cơ sở khoa học và tạo điều kiện thuận lợi cho việc buôn bán chứng chỉ carbon trên thị trường thương mại trong phạm vi quốc gia và toàn cầu.

scholarly journals Abundancia, tamaño y estructura poblacional del tiburón punta blanca de arrecife, Triaenodon obesus (Carcharhiniformes: Carcharhinidae), en Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica

2017 ◽  
pp. 339-346
Author(s):  
Ilena Zanella ◽  
Andrés López-Garro ◽  
Geiner Golfín-Duarte ◽  
Joel C. Sáenz
Keyword(s):  
Population Structure ◽  
Costa Rica ◽  
Coral Reefs ◽  
Shallow Water ◽  
Relative Abundance ◽  
National Park ◽  
Average Length ◽  
Sphyrna Lewini ◽  
Baseline Information ◽  
Triaenodon Obesus

Abundance, size and population structure of whitetip reef sharks, Triaenodon obesus (Carcharhiniformes: Carcharhinidae), in Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica. Approximately 12 species of shark inhabit at Coco Island National Park (PNIC); some are migratory, such as the hammerhead shark (Sphyrna lewini) and whale shark (Rincodon typus), and others are resident, like the whitetip shark (Triaenodon obesus). The whitetip shark is a species related to coral reefs, it inhabits coastal environments and is nocturnal and, it is very common in tropical waters, but there are few studies worldwide. In fact, only short researches have been done about their behavior at PNIC. Therefore, this study aimed to give data about the abundance, size and population structure of the whitetip shark at Chatham Bay in Coco Island National Park, providing baseline information for monitoring its population which is also very vulnerable to climate change. In order to accomplish this aim, a mark-recapture method was used, as well as underwater visual counts to determine their relative abundance and visual recaptures at Chatham Bay. The most effective hours for tagging were between 18:00 and 22:00 (sunset), when the whitetip sharks were more active probably related to foraging behavior. In addition, the depth was a relevant factor for tagging, sharks were caught in shallow water (10.9±1.9m). This species prefers to feed in shallow water and this behavior is probably related to the distribution and occurrence of rock and coral reefs in Chatham Bay. Based on the results, whitetip shark do not have a defined spatial ontogenic segregation, since in the same sites both juveniles and adults were found. The study confirmed that whitetip shark use specific residence sites: during the tagging trips, different individuals were recaptured; and during the underwater counts, at least 32.76% of tagged sharks were observed. The average length of the tagged sharks was 101.8±12.1cm (130.0cm maximum and 71.0cm minimum). The relative abundance of the whitetip shark in Chatham Bay observed was estimated on 49.5±10.4 sharks/hour. Furthermore, using the recapture data obtained during the night tagging expeditions, a population of 408 (IC = 181-1050) sharks was estimated. Citation: Zanella, I., A. López-Garro, G. Golfín-Duarte & J.C. Sáenz. 2012. Biología del tiburón punta blanca de arrecife, Triaenodon obesus (Carcharhiniformes: Carcharhinidae), en Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica. Rev. Biol. Trop. 60 (Suppl. 3): 339-346. Epub 2012 Dec 01.

scholarly journals Shallow Water Seabed Profile Changes in 2016 - 2018 Based on Landsat 8 Satellite Imagery (Case Study: Semak Daun Island, Karya Island and Gosong Balik Layar)

Omni-Akuatika ◽  
2020 ◽  
Vol 16 (3) ◽  
pp. 26
Author(s):  
Zahra Safira Aulia ◽  
Triguardi Tharik Ahmad ◽  
Ratih Rachma Ayustina ◽  
Fauzi Tri Hastono ◽  
Rizqi Rizaldi Hidayat ◽  
...  
Keyword(s):  
Shallow Water ◽  
Satellite Imagery ◽  
Accuracy Assessment ◽  
Satellite Image ◽  
Benthic Habitat ◽  
Landsat 8 ◽  
Marine Tourism ◽  
Profile Changes ◽  
High Level

Seribu Islands is one of the marine tourism destinations in  Jakarta. The high level of tourism in the Seribu Islands can be a threat to shallow water seabed profile habitat. Therefore, monitoring of changes in shallow water seabed profile habitat is needed so the sustainability can be monitored. This study aimed to determine changes in the shallow water seabed profile on Karya Island, Semak Daun Island, and Gosong Balik Layar in 2016 and 2018 based on Landsat 8 Satellite Imagery. Methods of this research used satellite image pre-processing, image classification, field survey, image reclassification, and accuracy assessment.  The results showed that the coral area had decrease trend, while the area of Seagrass mix Seaweed had increased. The result of this classification had an accuracy value of 71.52%. Keywords: remote sensing, multispectral imagery, Lyzenga, benthic habitat, Seribu Island

scholarly journals Distribution of shallow water soft and hard bottom seabeds in the Isla del Coco National Park, Pacific Costa Rica

2017 ◽  
pp. 53-66
Author(s):  
Jeffrey A. Sibaja-Cordero ◽  
Jesús S. Troncoso ◽  
Catalina Benavides-Varela ◽  
Jorge Cortés
Keyword(s):  
Costa Rica ◽  
Shallow Water ◽  
National Park ◽  
Field Data ◽  
Shallow Waters ◽  
Gis Applications ◽  
Marine Habitats ◽  
Clastic Sediments ◽  
Coarse Grains ◽  
Hard Substrates

Geographic Information Systems (GIS) applications used in marine habitats are powerful tools for management and monitoring of marine reserves and resources. Here, we present a series of maps of the soft and hard substrates in the shallow waters (>80 m depth) of Parque Nacional Isla del Coco (PNIC= Isla del Coco National Park). We use bathymetry data and field data as input for a GIS, GAM, and kriging methods to generate a series of maps that describe the bottom characteristics. Eight types of bottom were found in the PNIC by composition and grain size. The shore of the island and islets consisted of rocky formations (mainly basalts), with coral reefs in the subtidal of some areas. Rhodolith beds had a dispersing distribution. The bottom on the southern and southwestern region is hard substrate, while sediments cover the northern and northeastern zones. Slightly gravelly sand dominated the bays, while gravelly sand (with more coarse grains) was frequent offshore. The inner areas of Chatham and Wafer bays have mud and organic matter. The sediments in the area are mostly carbonates, except in Bahía Yglesias where clastic sediments (from the erosion of basalts) are presented. The information generated in this study could be a valuable input for future monitoring in the PNIC. Citation: Sibaja-Cordero, J.A., J.S. Troncoso, C. Benavides-Varela & J. Cortés. 2012. Shallow water soft and hard bottoms of Isla del Coco National Park, Pacific Costa Rica. Rev. Biol. Trop. 60 (Suppl. 3): 53-66. Epub 2012 Dec 01.

scholarly journals SHALLOW-WATER HABITAT CHANGE DETECTION OF KALEDUPA ISLAND, WAKATOBI NATIONAL PARK (WNP) FOR 14 YEARS

2018 ◽  
Vol 10 (2) ◽  
pp. 475-488
Author(s):  
Al Azhar Al Azhar ◽  
Ario Damar ◽  
Dietriech Geoffrey Bengen ◽  
Agus Atmadipoera
Keyword(s):  
Change Detection ◽  
Shallow Water ◽  
National Park ◽  
Habitat Change ◽  
Landsat 8 ◽  
Landsat 8 Oli

Metode penginderaan jauh sangat membantu dalam pemetaan kondisi habitat perairan dangkal secara spasial pada cakupan area yang luas. Penelitian ini bertujuan untuk menganalisis perubahan habitat perairan dangkal Pulau Kaledupa, Taman Nasional Wakatobi (TNW), selama 14 tahun, dari tahun 2002 hingga 2016. Data citra yang digunakan dalam penelitian ini adalah Landsat 8 OLI (2016), Landsat 5TM (2009), dan Landsat 7ETM+ (2002), yang dikombinasikan dengan data in-situ dan TNW. Klasifikasi Mahalanobis dimanfaatkan untuk memproduksi peta habitat perairan dangkal (karang hidup, karang mati, lamun, dan pasir) dan mendeteksi perubahannya. Hasil yang diperoleh bahwa perubahan yang terjadi dari tahun 2002 sampai 2016 adalah tutupan karang hidup menurun dari 2217 ha menjadi 2039 ha, tutupan karang mati juga menurun dari 3327 ha menjadi 2108 ha, luas pasir meningkat dari 1201 ha menjadi 1346 ha, area lamun naik dari 4130 ha menjadi 5294 ha. Metode ini merupakan alat analisis yang baik untuk menilai efektivitas upaya perlindungan ekosistem terumbu karang dan lamun di perairan Pulau Kaledupa, serta dapat diterapkan pada 3 pulau utama lainnya di TNW dan pulau-pulau kecil di Indonesia.

scholarly journals PERUBAHAN TUTUPAN TERUMBU KARANG DITINJAU DARI BANYAKNYA WISATAWAN DI TANJUNG GELAM KEPULAUAN KARIMUNJAWA MENGGUNAKAN CITRA SATELIT LANDSAT 8 OLI

2018 ◽  
Vol 7 (1) ◽  
pp. 18-27
Author(s):  
Moch Farid ◽  
Pujiono Wahyu Purnomo ◽  
Supriharyono Supriharyono
Keyword(s):  
Coral Reef ◽  
Coral Reefs ◽  
Coral Cover ◽  
Satellite Image ◽  
Landsat 8 ◽  
Living Coral ◽  
Ecosystem Sensitivity ◽  
High Productivity ◽  
The People ◽  
And Behavior

Terumbu karang merupakan salah satu sumberdaya pesisir dan lautan yang mempunyai produktifitas dan keanekaragaman hayati yang tinggi. Keberadaan terumbu karang banyak memberikan pengaruh pada masyarakat Karimunjawa, sebagai panorama alam yang menarik untuk kegiatan wisata. Penelitian ini bertujuan untuk mengetahui tingkat perkembangan wisata, tingkat sensitifitas dan kondisi terumbu karang serta perubahan luasanya di kawasan Tanjung Gelam. Penelitian dilaksanakan pada bulan Agustus 2017 bertempat di kawasan pemanfaatan bahari Tanjung Gelam, Kepulauan Karimunjawa Jepara. Metode pengukuran sensitifitas mengacu pada pengukuran kerentanan ekosistem terumbu karang parameter pengamatan yang diambil yaitu kondisi tutupan karang hidup, kerapatan terumbu karang, kelimpahan ikan, tipe pertumbuhan terumbu karang, status perlindungan, spesies yang dilindungi, dan kelandaian. Kuesisoner digunakan untuk mengetahu respon dan prilaku wisatawan pada kawasan tanjung gelam dengan jumlah responden yang diambil yaitu 25 wisatawan, 10 pedagang dan 10 operator wisata. Pengolaan citra satelit menggunakan transformasi Lyzenga. Hasil penelitian menunjukkan perkembangan wisata di Kepulauan karimunjawa dari tahun 2014-2016 mencapai kenaikan sebanyak 39.178 orang, sedangkan tingkat sensitifitas ekosisitem terumbu karang di kawasan tanjung gelam berada pada kategori rendah dengan nilai 2,14, dengan kondisi tutpan karang hidup pada kriteria rusak buruk dengan nilai rata rata 10,28% dan perubahan luasan tutupan terumbukarang di Tanjung Gelam didapatkan perubahan luasan habitat terumbu karang yang berkurang sebesar 4,22 Ha dari tahun 2015-2017. Coral reefs are one of the coastal and ocean resources that have high productivity and biodiversity. The existence of coral reefs give much influence to the people of Karimunjawa, as an interesting natural panorama for tourism activities. This research aims to determine the level of tourism development, the level of sensitivity and condition of coral reefs and changes in the area of Tanjung Gelam. The research was conducted in August 2017 located in Tanjung Gelam marine utilization area, Karimunjawa island of Jepara. Methods of measurement of sensitivity include the measurement of living coral cover conditions, coral reef density, fish abundance, coral growth type, protection status, protected species, and cleverness. Questionnaires are used to find out the responses and behavior of tourists in the region of Tanjung Pinam with the number of respondents taken are 25 tourists, 10 merchants and 10 tour operators. Satellite image managers use the Lyzenga transformation. The results showed that the development of tourism in Karimunjawa Islands from 2014-2016 reached as much as 39,178 people, while the level of coral reef ecosystem sensitivity in the region of Tanjung Pinang was in the low category with a value of 2.14, with the living coral study on badly damaged criteria with value the average of 10.28 and the change of cover area in Tanjung Gelam found a change in coral reef habitat area which decreased by 4.22 Ha from 2015-2017 year.

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