scholarly journals Assessing the Potential of Remotely-Sensed Drone Spectroscopy to Determine Live Coral Cover on Heron Reef

Drones ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 29
Author(s):  
Valerie J. Cornet ◽  
Karen E. Joyce
Keyword(s):  
Coral Cover ◽  
Economic Value ◽  
Spectral Unmixing ◽  
Future Research ◽  
Live Coral ◽  
Complex Environments ◽  
Spectral Signatures ◽  
Reef Health ◽  
Categorical Classification ◽  
Spectral Mixture

Coral reefs, as biologically diverse ecosystems, hold significant ecological and economic value. With increased threats imposed on them, it is increasingly important to monitor reef health by developing accessible methods to quantify coral cover. Discriminating between substrate types has previously been achieved with in situ spectroscopy but has not been tested using drones. In this study, we test the ability of using point-based drone spectroscopy to determine substrate cover through spectral unmixing on a portion of Heron Reef, Australia. A spectral mixture analysis was conducted to separate the components contributing to spectral signatures obtained across the reef. The pure spectra used to unmix measured data include live coral, algae, sand, and rock, obtained from a public spectral library. These were able to account for over 82% of the spectral mixing captured in each spectroscopy measurement, highlighting the benefits of using a public database. The unmixing results were then compared to a categorical classification on an overlapping mosaicked drone image but yielded inconclusive results due to challenges in co-registration. This study uniquely showcases the potential of using commercial-grade drones and point spectroscopy in mapping complex environments. This can pave the way for future research, by increasing access to repeatable, effective, and affordable technology.

scholarly journals Status of Coral Reefs in the Water of Spermonde, Makassar, South Sulawesi

2021 ◽  
Vol 324 ◽  
pp. 03007
Author(s):  
Ni Wayan Purnama Sari ◽  
Rikoh Manogar Siringoringo ◽  
Muhammad Abrar ◽  
Risandi Dwirama Putra ◽  
Raden Sutiadi ◽  
...  
Keyword(s):  
Coral Reef ◽  
Coral Reefs ◽  
Coral Cover ◽  
Public Awareness ◽  
Live Coral ◽  
Health Index ◽  
Point Count ◽  
Live Coral Cover ◽  
Reef Health ◽  
Index Value

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.

scholarly journals Simbiosis Zooxanthellae dan Karang Sebagai Indikator Kualitas Ekosistem Terumbu Karang

2012 ◽  
Vol 1 (1) ◽  
pp. 37 ◽  
Author(s):  
Unstain N W J Rembet
Keyword(s):  
Coral Reef ◽  
Quality Evaluation ◽  
Coral Cover ◽  
Evolutionary Process ◽  
Live Coral ◽  
Symbiotic Relationship ◽  
Health Status Measure ◽  
Environmental Pressures ◽  
Status Measure ◽  
Reef Health

TINJAUAN TEORITIS SIMBIOSIS ZOOXANTHELLAE DAN KARANG SEBAGAI INDIKATOR KUALITAS EKOSISTEM TERUMBU KARANG   Unstain NWJ Rembet1   ABSTRACT   A symbiotic process between zooxanthellae and corals can support the adaptative factors in terms of natural vulnerability criteria. The proposed consideration are 1) the symbiosis between zooxanthellae and corals provides phenomenal contributions to coral evolutionary process and 2) the criteria used by Gomez and Yap have been merely based on live coral cover that is still becoming key tools for the evaluation of coral reef health status measure. These criteria have been weaker and weaker due to neglecting the feature of intra- and interspesific relationship in coral biota itself. Therefore, the use of zooxanthellae and coral symbiotic relationship is thought of being able to complete the coral reef quality evaluation since its information could address this relationship feature beside on the basis of response to environmental pressures.     Keywords : symbiotic, zooxanthellae, coral.   ABSTRAK Proses simbiosis antara zooxanthellae dengan karang dapat memberikan suatu support terhadap faktor penyesuai dalam hal ini dari segi kriteria kerentanan alami. Pertimbangan yang diajukan adalah (1) simbiosis antara karang dengan zooxanthellae memberikan konstribusi fenomenal dalam proses evolusi karang dan (2) kriteria yang dipergunakan saat ini dari analisis Gomez dan Yap hanya didasarkan atas tutupan karang hidup yang sampai sekarang menjadi acuan bagi evaluasi tingkat status kesehatan terumbu. Kriteria tersebut dipandang mengalami kelemahan karena mengabaikan sifat hubungan intra dan ekstraspesifik dari biota karang itu sendiri. Atas dasar hal tersebut, maka penggunaan hubungan simbiosis zoxanthellae dan karang dipandang dapat melengkapi evaluasi kualitas terumbu karang karena informasinya dapat menjelaskan sifat hubungan intra dan ekstra spesifik, disamping atas dasar respon terhadap tekanan lingkungan.     Kata kunci : simbiosis, zooxanthellae, karang.       1 Laboratorium Pengelolaan Wilayah Pesisir Terpadu, FPIK UNSRAT

scholarly journals Quantification of The Effects of Coral Reef Degradation On Butterflyfish Populations in The Southern Great Barrier Reef

2021 ◽  
Vol 4 (1) ◽  
Keyword(s):  
Coral Reef ◽  
Coral Cover ◽  
Fish Abundance ◽  
Live Coral ◽  
Reef Degradation ◽  
Significant Difference ◽  
Reef Health ◽  
Coral Reef Degradation ◽  
Abundance And Diversity ◽  
A Minor

Because of their wide abundance on coral reefs, butterflyfishes’ presence or absence can function as an indicator for overall reef health. A survey of both healthy and degraded coral reef flats off Heron Island in Queensland, Australia was conducted to determine the effects of decreasing coral cover on corallivorous fishes. During a four-day period at the end of October, 2013, four species of butterflyfish – two obligate and two facultative corallivorous butterflyfish species – were tallied along two transects in the reef flats. From a total of 291 individuals, there was a significant difference in habitat composition choice between healthy and degraded habitats seen by a p= 2.234e-10. Additionally, means extracted from log-transformed data suggest that the twelve percent decrease in live coral between transects of the healthy habitat caused a disproportionate decrease in fish abundance. This suggests that a minor loss of coral cover can result in a dramatic loss of fish abundance and diversity and may point towards a threshold where living coral can no longer sustain original population abundances of coral reef communities.

SHALLOW WATER HABITAT MAPPING AND REEF FISH STOCK ESTIMATION USING HIGH RESOLUTION SATELLITE DATA

2013 ◽  
Vol 5 (2) ◽  
Author(s):  
Vincentius P. Siregar ◽  
Sam Wouthuyzen ◽  
Andriani Sunuddin ◽  
Ari Anggoro ◽  
Ade Ayu Mustika
Keyword(s):  
High Resolution ◽  
Reef Fish ◽  
Satellite Imagery ◽  
Field Survey ◽  
Coral Cover ◽  
Fish Density ◽  
Fish Stock ◽  
Benthic Habitat ◽  
Live Coral ◽  
Stock Estimation

Shallow marine waters comprise diverse benthic types forming habitats for reef fish community, which important for the livelihood of coastal and small island inhabitants. Satellite imagery provide synoptic map of benthic habitat and further utilized to estimate reef fish stock. The objective of this research was to estimate reef fish stock in complex coral reef of Pulau Pari, by utilizing high resolution satellite imagery of the WorldView-2 in combination with field data such as visual census of reef fish. Field survey was conducted between May-August 2013 with 160 sampling points representing four sites (north, south, west, and east). The image was analy-zed and grouped into five classes of benthic habitats i.e., live coral (LC), dead coral (DC), sand (Sa), seagrass (Sg), and mix (Mx) (combination seagrass+coral and seagrass+sand). The overall accuracy of benthic habitat map was 78%. Field survey revealed that the highest live coral cover (58%) was found at the north site with fish density 3.69 and 1.50 ind/m2at 3 and 10 m depth, respectively. Meanwhile, the lowest live coral cover (18%) was found at the south site with fish density 2.79 and 2.18  ind/m2 at 3 and 10 m depth, respectively. Interpolation on fish density data in each habitat class resulted in standing stock reef fish estimation:  LC (5,340,698 ind), DC (56,254,356 ind), Sa (13,370,154 ind), Sg (1,776,195 ind) and Mx (14,557,680 ind). Keywords: mapping, satellite imagery, benthic habitat, reef fish, stock estimation

Coral reef condition in several dive points around Bunaken Island, North Sulawesi

2014 ◽  
pp. 44
Author(s):  
Robert Towoliu
Keyword(s):  
Coral Reef ◽  
Coral Cover ◽  
Integrated Management ◽  
Good Condition ◽  
Live Coral ◽  
Core Zone ◽  
Integrated Management System ◽  
North Sulawesi ◽  
Live Coral Cover ◽  
Reef Condition

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.

scholarly journals Economic value of protected areas via visitor mental health

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Ralf Buckley ◽  
Paula Brough ◽  
Leah Hague ◽  
Alienor Chauvenet ◽  
Chris Fleming ◽  
...  
Keyword(s):  
Mental Health ◽  
Protected Areas ◽  
Protected Area ◽  
Economic Value ◽  
Future Research ◽  
Global Estimate ◽  
Conservation Policies ◽  
Life Years ◽  
Order Of Magnitude ◽  
Individual Scale

Abstract We evaluate methods to calculate the economic value of protected areas derived from the improved mental health of visitors. A conservative global estimate using quality-adjusted life years, a standard measure in health economics, is US$6 trillion p.a. This is an order of magnitude greater than the global value of protected area tourism, and two to three orders greater than global aggregate protected area management agency budgets. Future research should: refine this estimate using more precise methods; consider interactions between health and conservation policies and budgets at national scales; and examine links between personalities and protected area experiences at individual scale.

Algoritmo de Descomposición Ciega Basado en el Modelo de Mezcla Multi-Lineal

2021 ◽  
Author(s):  
◽  
J. N. Mendoza Chavarría
Keyword(s):  
State Of The Art ◽  
Hyperspectral Data ◽  
Spectral Unmixing ◽  
Mixing Models ◽  
Nonlinear Interactions ◽  
Estimation Errors ◽  
Spectral Signatures ◽  
Scattering Effects ◽  
Linear Unmixing ◽  
Multiple Light Scattering

Spectral unmixing has proven to be a great tool for the analysis of hyperspectral data, with linear mixing models (LMMs) being the most used in the literature. Nevertheless, due to the limitations of the LMMs to accurately describe the multiple light scattering effects in multi and hyperspectral imaging, new mixing models have emerged to describe nonlinear interactions. In this paper, we propose a new nonlinear unmixing algorithm based on a multilinear mixture model called Non-linear Extended Blind Endmember and Abundance Extraction (NEBEAE), which is based on a linear unmixing method established in the literature. The results of this study show that proposed method decreases the estimation errors of the spectral signatures and abundance maps, as well as the execution time with respect the state of the art methods.

scholarly journals Apparent stability of a low-density Diadema antillarum regime for Puerto Rican coral reefs

2018 ◽  
Vol 75 (6) ◽  
pp. 2193-2201 ◽  
Author(s):  
Ruber Rodríguez-Barreras ◽  
Alfredo Montañez-Acuña ◽  
Abimarie Otaño-Cruz ◽  
Scott D Ling
Keyword(s):  
Puerto Rico ◽  
Sea Urchin ◽  
Coral Cover ◽  
Live Coral ◽  
Low Density ◽  
Limited Evidence ◽  
Diadema Antillarum ◽  
Benthic Habitats ◽  
Stable Regime ◽  
Apparent Stability

Abstract Caribbean reefs have suffered decline in coral cover in recent decades due to recurrent anthropogenic and natural stressors. The regional collapse of the sea urchin Diadema antillarum, combined with overfishing, has contributed to a phase-shift of coral reef communities towards fleshy macroalgal dominance. Here, we examine the population dynamics of D. antillarum at five sites in Puerto Rico from 2011 to 2016 and determine trends between the sea urchin and local benthic habitats. The sea urchin population exhibited low but stable densities (with slight, but non-significant trend of increase), yet showed variability between sites. Large urchins (>60 mm test diam.) were the most abundant across sites and through time, followed by medium urchins (41–60 mm test diam.), whereas small individuals (<40 mm) were rare, indicating recruitment-limitation. Spatial and temporal differences in benthic habitats were not related to local D. antillarum abundances. Macroalgae cover declined at all sites over the 6 years, ranging 5–86%, whereas live coral cover also decreased across all sites (ranging 4–38%). Diadema antillarum populations in Puerto Rico appear stable with limited evidence for recovery trends back to pre-mass mortality densities. Full population recovery may take longer than expected; however, evidence indicates that the contemporary low-density D. antillarum population represents a novel stable regime.

scholarly journals Towards an integrated network of coral immune mechanisms

2012 ◽  
Vol 279 (1745) ◽  
pp. 4106-4114 ◽  
Author(s):  
C. V. Palmer ◽  
N. Traylor-Knowles
Keyword(s):  
Coral Disease ◽  
Rapid Development ◽  
Economic Value ◽  
Mechanistic Explanation ◽  
Future Research ◽  
Integrated Network ◽  
Immune Mechanisms ◽  
Invertebrate Immunology ◽  
Ecological Scale ◽  
Stress Susceptibility

Reef-building corals form bio-diverse marine ecosystems of high societal and economic value, but are in significant decline globally due, in part, to rapid climatic changes. As immunity is a predictor of coral disease and thermal stress susceptibility, a comprehensive understanding of this new field will likely provide a mechanistic explanation for ecological-scale trends in reef declines. Recently, several strides within coral immunology document defence mechanisms that are consistent with those of both invertebrates and vertebrates, and which span the recognition, signalling and effector response phases of innate immunity. However, many of these studies remain discrete and unincorporated into the wider fields of invertebrate immunology or coral biology. To encourage the rapid development of coral immunology, we comprehensively synthesize the current understanding of the field in the context of general invertebrate immunology, and highlight fundamental gaps in our knowledge. We propose a framework for future research that we hope will stimulate directional studies in this emerging field and lead to the elucidation of an integrated network of coral immune mechanisms. Once established, we are optimistic that coral immunology can be effectively applied to pertinent ecological questions, improve current prediction tools and aid conservation efforts.

scholarly journals CONDITION OF CORAL AND REEF FISH IN THE LOCATION OF FISH CATCHING USING DYNAMITE FISHING IN KAPOPOSANG WATER PARK AND THE SURROUNDING SEA

2020 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Mahmudin Mahmudin ◽  
Chair Rani ◽  
Hamzah Hamzah
Keyword(s):  
Coral Reef ◽  
Reef Fish ◽  
Coral Cover ◽  
Low Cost ◽  
Fish Abundance ◽  
Live Coral ◽  
Coral Reef Ecosystem ◽  
Control Location ◽  
Target Fish ◽  
Reef Ecosystem

Dynamite fishing is one of the causes of damage to the coral reef ecosystem in Indonesia. Fishing activities using explosives (dynamite fishing) occur because of the desire of fishermen to get a lot of catch with low cost in a short time. Kapoposang Water Park (WP) is a region rich in marine biological resources. However, dynamite fishing activities which are still found within the area have caused the coral reef ecosystem to be severely damaged. The results showed a lower difference in the percentage of live coral cover at dynamite fishing locations (DF1, DF2) compared to control locations (K1, K2). In addition, the highest average values of coral fish abundance were found at locations K1, DF1, and DF2. Conversely, the results of the analysis found the lowest fish abundance at the K2 location. Different from the average number of reef fish species that were higher at the control location (K1, K2) compared to dynamite fishing locations (DF1, DF2). For the target fish biomass there is no real difference between the control location and dynamite fishing.

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