Coral Aquaculture Research Articles

Oceanographic‐informed coral out‐planting density for coral reef restoration activities

Out‐planting corals onto coral reefs as a mechanism to increase coral cover on degraded reef systems is an increasing global activity. Current practices typically focus on asexual out‐planting of coral fragments (coral gardening). Newer sexual reproductive approaches are being developed to out‐plant younger corals produced in aquaculture facilities or sea‐based rearing pools to enable assisted evolution or assisted gene flow conservation genetics approaches. Designing out‐planting deployment operations requires decisions to be made on planting density and location in order to maximize future recruitment on both the out‐planted reefs, and on nearby reefs that are connected through oceanographic transport processes. The thinking presented here seeks to unpack how out‐planting density may be influenced, especially by local oceanographic conditions, in order to guide practitioners undertaking restoration projects.

Testing the feasibility of coral nurseries in an upwelling area in the North Pacific of Costa Rica

The decline of coral reefs has increased interest in ecological restoration. Due to the scarcity of coral gardening projects in the Eastern Tropical Pacific, improving our understanding of such techniques is key. We report the results of coral gardening using the branching Pocillopora spp. and massive coral species (Pavona gigantea, Pavona clavus and Porites lobata) in an upwelling area in Costa Rica. We examined whether nursery type influenced Pocillopora spp. survival and growth, and how environmental conditions shaped restoration. We monitored the survival and growth of Pocillopora spp. fragments (n = 334) and microfragments of massive species (P. gigantea [n = 148], P. clavus [n = 37], P. lobata [n = 66]) over 11 months. Survival at the end of the gardening period was 51% for Pocillopora spp., 59% for P. clavus, 55% for P. gigantea, and 17% for P. lobata, with a decline after a cease in maintenance caused by the COVID-19 lockdown. Pocillopora spp. fragments in the floating nurseries exhibited higher growth (7.52 ± 1.98 and 6.64 ± 2.91 cm yr-1) than in the A-frame (4.16 ± 2.35 cm yr-1), which suggests the benefits of suspending fragments. For massive microfragments coral growth was 1.92-4.66 cm2 yr-1 and were affected by pigmentation loss, causing partial tissue loss and mortality. Our results point towards acclimation to local conditions, and show the need to develop site-specific cost-efficient gardening techniques for massive species, allowing for a multi-species approach to ensure long-term ecosystem recovery.

Northern coral triangle coral ciliates diseases and disease prevention: A first record

This study is the first to report ciliate infection on soft corals in the Northern Coral Triangle. Infected Briareum violacea will undergo tissue ulceration and death within a short period of time. This ciliate was identified as Scuticociliatia sp. through 18S rRNA gene identification. In this study, the body length of the ciliate was approximately 80–85 μm before parasitizing the B. violacea. After being parasitizing, the body length was approximately 200–250 μm, and the body width was 50 μm. Body size increased three times after parasitism. According to observations, ciliates will first parasitize the coral endoderm in the early stage of infection, and no ciliates were found in the ectoderm. Preliminary judgment suggests that it may invade the coral endoderm through the mouth for parasitism. After parasitism, the ciliate eats the coral tissue and zooxanthellae. The antioxidant enzymes SOD, CAT, and MDA of infected corals were significantly increased, which also means that the corals are in a stress response. Ciliates will eat the zooxanthellae in the coral body, resulting in a significant reduction in the number of zooxanthellae and chlorophyll a. To effectively prevent and treat this disease, Combretum indicum extract was used in this study. It is a tropical plant commonly used medicinally to treat roundworms, pinworms and parasitic diseases. The results showed that at a concentration of 1500–2500 ppm, Combretum indicum extract can be used to treat ciliates and can applied via medicinal bath therapy for long periods without causing coral stress reactions. The results of this study regarding coral disease prevention are in line with SDG 14 and promote the practical application of coral reef ecological sustainability and large-scale coral aquaculture.

From Sea to Science: Coral Aquaculture for Sustainable Anticancer Drug Development.

Marine natural products offer immense potential for drug development, but the limited supply of marine organisms poses a significant challenge. Establishing aquaculture presents a sustainable solution for this challenge by facilitating the mass production of active ingredients while reducing our reliance on wild populations and harm to local environments. To fully utilize aquaculture as a source of biologically active products, a cell-free system was established to target molecular components with protein-modulating activity, including topoisomerase II, HDAC, and tubulin polymerization, using extracts from aquaculture corals. Subsequent in vitro studies were performed, including MTT assays, flow cytometry, confocal microscopy, and Western blotting, along with in vivo xenograft models, to verify the efficacy of the active extracts and further elucidate their cytotoxic mechanisms. Regulatory proteins were clarified using NGS and gene modification techniques. Molecular docking and SwissADME assays were performed to evaluate the drug-likeness and pharmacokinetic and medicinal chemistry-related properties of the small molecules. The extract from Lobophytum crassum (LCE) demonstrated potent broad-spectrum activity, exhibiting significant inhibition of tubulin polymerization, and showed low IC50 values against prostate cancer cells. Flow cytometry and Western blotting assays revealed that LCE induced apoptosis, as evidenced by the increased expression of apoptotic protein-cleaved caspase-3 and the populations of early and late apoptotic cells. In the xenograft tumor experiments, LCE significantly suppressed tumor growth and reduced the tumor volume (PC3: 43.9%; Du145: 49.2%) and weight (PC3: 48.8%; Du145: 7.8%). Additionally, LCE inhibited prostate cancer cell migration, and invasion upregulated the epithelial marker E-cadherin and suppressed EMT-related proteins. Furthermore, LCE effectively attenuated TGF-β-induced EMT in PC3 and Du145 cells. Bioactivity-guided fractionation and SwissADME validation confirmed that LCE's main component, 13-acetoxysarcocrassolide (13-AC), holds greater potential for the development of anticancer drugs.

Priority sites for coral aquaculture in Kume Island based on numerical simulation

Global and local stresses such as increased water temperature and terrestrial sediment runoff significantly affect coral reef ecosystems. Over the past three decades, the increase in the intensity and frequency of coral bleaching has been a significant problem in tropical and subtropical coastal seas, and maintaining healthy coral reef ecosystems has long been a challenge. Coral cover in Shimajiri Bay on Kume Island, located in the Nansei Islands (Okinawa Prefecture, southern Japan), has declined due to exposure to high water temperatures, an outbreak of coral predators, and sediment (red soil) inflow from the land. From such a background, coral aquaculture has been implemented at a few stations in the bay. Therefore, it is essential to conduct aquaculture in suitable locations for coral growth and survival. This study aimed to select suitable locations for coral culture with high spatial resolution in an enclosed bay that was greatly affected by red soil runoff, mainly from a sugarcane field. A freshwater and red soil runoff model for the watershed was merged with a coastal hydrodynamic, red soil dispersal, and accumulation model at a spatial resolution of 75 m for Shimajiri Bay. The simulation results were validated using in situ continuous and routine observations. Simulations were conducted over ten years. Locations not subjected to high water temperature in the bay or river loading were selected based on topography, simulated water temperature, salinity, and red soil content of sea sediment. This coupled model enables us to evaluate the growth and survival conditions of cultured corals with high spatiotemporal resolution and quantitatively consider the reduction target of red soil runoff to realize robust coral growth and survival.

Coral mariculture using abandoned abalone farming ponds in northeastern Taiwan

Stony corals are ecologically and economically important marine organisms. Coral aquaculture is essential to provide live coral materials for the marine ornamental trade, reef restoration programs, and environmental education. This study sought to establish coral farms in Taiwan. To culture corals, we adopted an abandoned abalone farming pond built along the northeastern coast of Taiwan, and investigated whether it is possible to propagate corals in this artificial environment. Stainless steel underwater tables were anchored to the pond floor, and fragments of Acropora tumida, Pocillopora damicornis, Stylophora pistillata, Favites pentagona, and Porites lobata were cultured on the tables for one year. Environmental factors in the pond were also monitored. The mean surface temperature was 23.07 °C, ranging from >30 °C in summer to 18 °C in winter. The mean salinity and pH were about 35 ppt and 8.14, respectively. Survivorship of these five species after one year ranged from 100% to 67%, with a 1.37–1.51-fold increase in weight and a 3.22–3.38-fold increase in area, demonstrating that although environmental factors fluctuate depending on the season and weather, long-term and stable asexual propagation of corals is feasible in the pond. For further optimization of culture conditions, the effects of initial fragment size for culture on subsequent survival and growth were investigated. Fragments of 3 sizes (1.5, 3.0, and 4.5 cm) were prepared from parental colonies of A. tumida, P. damicornis, and S. pistillata and cultured for 6 months by hanging them under the table. There were no significant differences in survivorship among these sizes. Differences were observed in biomass (weight) increase. In A. tumida, 3-cm fragments showed significantly more weight gain than other lengths, while 1.5-cm fragments showed a significant weight increase in P. damicornis. In S. pistillata, no significant difference in weight increase was observed among size groups, suggesting the necessity to optimize the initial fragment size for culture for each species before mass culture. Histological analysis showed that mature gametes were formed in some cultured corals, suggesting that sexual propagation may also be possible in the future. The established coral farm, which is culturing >4000 coral fragments now, will be able to support not only basic and applied coral research, but also sustainable reef development and marine ornamental trade.

Impact of the COVID-19 Pandemic on the Management of Coral Aquaculture

This research aims to determine the impact of the COVID-19 pandemic on coral aquaculture businesses and management strategies in dealing with the pandemic. This research was a quantitative descriptive research. This research used the triangulation method (questionnaire, interview, and observation). This research was conducted at three coral aquaculture companies and a cultured coral transplantation site owned by a private company in Bali. The results showed that the COVID-19 pandemic had a more favorable impact on the coral aquaculture industry, such as the ability to become a source of income for the locals during the pandemic. The difficulties in conducting export activities and restricted mobility were some of the challenges encountered by coral aquaculture businesses during the pandemic. Additionally, the results showed that in order for coral aquaculture businesses to survive the pandemic, management strategies and adaptations are needed.

Sponge-derived matter is assimilated by coral holobionts

Coral reef biodiversity is maintained by a complex network of nutrient recycling among organisms. Sponges assimilate nutrients produced by other organisms like coral and algae, releasing them as particulate and dissolved matter, but to date, only a single trophic link between sponge-derived dissolved matter and a macroalgae has been identified. We sought to determine if sponge-coral nutrient exchange is reciprocal using a stable isotope ‘pulse-chase’ experiment to trace the uptake of 13C and 15N sponge-derived matter by the coral holobiont for three coral species (Acropora cervicornis, Orbicella faveolata, and Eunicea flexuosa). Coral holobionts incorporated 2.3–26.8x more 15N than 13C from sponge-derived matter and A. cervicornis incorporated more of both C and N than the other corals. Differential isotopic incorporation among coral species aligns with their ecophysiological characteristics (e.g., morphology, Symbiodiniaceae density). Our results elucidate a recycling pathway on coral reefs that has implications for improving coral aquaculture and management approaches.

Propagating the stony coral Echinopora horrida: evaluating the effects of rearing environment and transplant orientation

The “coral gardening” approach has been effective in facilitating the recovery of degraded reefs but methodological variations can influence survivorship and growth of the coral material. In addition, the disproportionate use of certain corals, such as acroporids and pocilloporids, has contributed to a general lack of information on growth patterns and restoration strategies for species that are less common. To investigate how the yield of other species may be increased to support reef restoration efforts in Singapore, we assessed the effects of (1) environment (nursery, reef, and seawall) and (2) transplant orientation (horizontal and vertical) on the performance of Echinopora horrida (Dana, 1846) fragments. Fragments secured in the coral nursery grew significantly faster and survived better than those transplanted on the reef and seawall, highlighting the importance of a nursery‐rearing phase in optimizing the yield of this species. Additionally, survivorship and growth rates were not significantly different between vertically and horizontally transplanted corals, suggesting that modifying transplant orientation was less crucial toward enhancing coral yield. Our findings highlighted the need to optimize the propagation techniques of a wider range of understudied coral species in order to preserve their genetic diversity in the face of anthropogenic and climatic impacts.

Disease assessment in ‘coral gardening’ nurseries in the Maldives and implications for coral restoration success

Disease assessment in ‘coral gardening’ nurseries in the Maldives and implications for coral restoration success

Size matters: Microherbivores make a big impact in coral aquaculture

Reef restoration activities and the ornamental trade are increasing the demand for sexually propagated corals. One challenge faced in scaling up the aquaculture production of corals is high mortality as a result of fouling organisms overgrowing coral spat, with manual removal of algae and other fouling organisms being costly and time consuming. Here we test the use of microherbivore grazers as a potential biocontrol method for fouling in coral aquaculture and compare their effectiveness to manual cleaning by an aquarist. Recruits of six coral species (Acropora millepora, Acropora kenti, Goniastrea retiformis, Porites lobata, Dipsastraea speciosa and Lobophyllia corymbosa) were reared for 112 days with aquarist cleaning, or co-cultured with gastropods (Calthalotia strigata or Turbo haynesi), sea urchins (Tripneustes gratilla or Echinomentra mathaei), the hermit crab Clibanarius cf. taeniatus or under a control treatment with no grazers. Corals grown in the aquarist cleaning treatment displayed high survival and growth, though similar responses were observed for most coral species grown with C. strigata or T. gratilla, likely due to minimal damage via overgrazing and the promotion of relatively short turf algal communities in these treatments. However, effort required, measured as average cleaning time, was 2–3 times greater in the aquarist treatment compared to C. strigata or T. gratilla treatments. Survival of coral recruits housed with C. cf. taeniatus, E. mathaei or T. haynesi were variable, likely due to the dominance of long, filamentous turf algae in tanks with E. mathaei, and physical disturbance to recruits by C. cf. taeniatus and T. haynesi. Our results demonstrate microherbivores have potential for application in aquaculture to promote production, while also reducing labour costs.

Citizen science benefits coral reefs and community members alike

The field of coral gardening and active restoration has expanded rapidly over the past 2 decades in response to the rapid, global decline of coral reefs. Even with this expansion, the long-term success of coral restoration and ecosystem recovery will still depend on social action to mitigate the local and global stressors plaguing reefs. Rescue a Reef (RAR), a citizen science program, was designed to engage community members and catalyze action through hands-on, experiential opportunities as coral gardeners and restoration practitioners alongside trained scientists. While community-based coral restoration programs can be a powerful platform for education and increase project success, few programs utilize citizen science and even fewer measure and evaluate the long-term impacts of these activities. Here, we describe the benefits of citizen science for coral conservation identified through a mixed methods longitudinal evaluation of RAR after 8 years of citizen science programming. A survey was distributed to all program participants and responses were compared to historical pre-post survey responses of citizen scientists as well as to a control group. We found that despite the passing of time, citizen scientists largely retained their knowledge levels on coral reef-related topics and were significantly more knowledgeable on the topics than a control group. Additionally, RAR successfully developed a strong sense of community, coral stewardship, and program support among its participants. Most importantly, citizen science has the potential to act as a vehicle for positive social change with the majority of participants reporting changes in perceptions (70.5%) and behavior (60.1%) because of their participation in RAR. Thus, the untapped potential of citizen science as a tool for coral reef conservation, restoration, and stewardship must be realized. Furthermore, citizen science projects must embed evaluation in their activities to gather information and evidence on the effectiveness of their activities as well as potential areas for improvement.

Gardening Pocillopora spp. fragments and their potential for rebuilding reef systems in the southern Mexican Pacific

The degradation of coral reefs during the last decades has turned attention toward management and restoration interventions. This study seeks to operationalize coral gardening of Pocillopora spp. fragments in low profile bottom‐anchored nurseries and to compare survival and growth patterns between sites, time, and fragment size in the southern Mexican Pacific. After 357 days, fragments showed high survival (96.4%), growth rates (4.35 cm/year), and an increase in coral coverage from 3.62 ± 1.3% (mean ± SD) to 17.42 ± 4.8% (approximately 480%). Coral growth rate did not show differences between sites (pseudo‐F[1,635] = 0.21, p = 0.63), but corals grew more significantly during the upwelling season in the Gulf of Tehuantepec. According to linear and local regression analysis, the extension rate in nurseries was significantly higher when corals were smaller (<7 cm in diameter) being of relevance for operationalizing coral gardening from donor colonies; nevertheless, coral shrinkage (13.1%), when corals were smaller (i.e. during the early phases of the coral gardening protocol), calls for precaution and close monitoring. Operationalizing coral gardening of Pocillopora spp. fragments, including successful metrics in upwelling areas, are relevant for reef restoration in the eastern tropical Pacific; nevertheless, lessons regarding shrinkage and differential growth rates related to coral size should also be considered.

Exploring New Frontiers in Coral Nurseries: Leveraging 3D Printing Technology to Benefit Coral Growth and Survival

Coral nurseries and associated techniques are the most common and widespread reef restoration methods worldwide. Due to the rapid decline of coral reefs, coral nurseries need to be eco-friendlier and adapted for effective upscaling to support large restoration projects. We suggest new design and fabrication processes associated with coral gardening and transplantation with 3D printing technology to offer a beneficial solution for growing coral fragments in on-land and underwater nurseries. We describe multiple combinations of building nurseries through the integration of biomimetic substrates and novel solutions for attaching coral fragments. Our methods are supported with supplemental testing of two hybrid substrate designs and coral mounting structures, building upon previous studies in the Gulf of Eilat/Aqaba (GoE/A), Red Sea. We identified and quantified marine invertebrates colonizing the surfaces of our substrates with environmental DNA (eDNA) by targeting the mitochondrial COI gene. We evaluated our coral fragments with and without our mounting structures to obtain an indication of total protein as a proxy for tissue health. We demonstrate the ability to design hybrid nurseries with custom mounting structures using biomimetic substrates, such as large ceramic artificial reefs, or with an interlocking mesh for holding numerous fragments to maximize out-planting efforts. We propose several methods for both land and underwater nurseries catered to various restoration initiatives for cost-effective up-scaling to meet the demands of global reef restoration.

Symbiotic communities associated with nursery-reared and natural corals: are they similar?

Coral aquaculture techniques have been developed for many species based on a well-documented understanding of the factors that affect coral growth and fitness. However, there is limited knowledge about the composition and structure of ectosymbiotic communities associated with cultured coral colonies. To address this gap, we conducted a study ofPocillopora verrucosacolonies reared from fragments in fixed nurseries and exposed for 6 and 12 months, as well as natural colonies in the same location. Our analysis focused on the species composition, species richness, and density of obligate and facultative ectosymbionts associated with the colonies. Obtained results indicate that the community associated with nursery-reared colonies was highly diverse, comprising 25 ectosymbionts, including 9 obligate and 16 facultative species. The prevalence, species richness, and density of the communities associated with natural colonies were significantly higher than those associated with reared ones. We also observed differences in the communities associated with reared colonies of different exposures, but we were able to group them as stages of the same community based on the size and exposure of the colonies. The differences between communities associated with reared and natural colonies may be related to the microhabitat properties of the symbiotic communities, as the former were elevated above the substrate, while the latter were attached to it. The age of natural colonies was also estimated to be more than three times higher than that of reared colonies of the same size, contributing to the differences. Our study clearly demonstrates that coral nurseries not only serve as a means of propagating corals but also offer artificial habitats for the maintenance and conservation of associated fauna. These findings have important implications for the management and conservation of coral reefs.

A Review of Coral Reef Restoration Methods

Due to global warming and human activity, the coral population has decreased by 50% since the 1950s. (Wetzel, 2021). Many policies have been placed on conserving the coral reefs, but more is needed to stop the rapid decline. All around the world, different researchers performed multiple types of restoration methods to try and reverse the damage and destruction the coral reef ecosystem has sustained. This paper reviews the other restoration methods researchers have tried and are currently trying to review their effectiveness in reversing the damage to coral reefs. Restoration methods can be divided into active and passive restoration methods. The methods reviewed are removing invasive algae, coral gardening, substrate manipulation, and stabilization, larval propagation, direct transplantation, substratum enhancement with electricity, and cryopreservation. All in all, all of these methods have their respective strengths and weaknesses. The method that can move forward to be more mass-produced would be direct transplantation, as additions such as nurseries are unnecessary. The restoration method that has shown the most promise has been substratum enhancement with electricity, but since the method is still relatively new, further research is needed. A possible recommendation for future coral reef restoration endeavors is to combine restoration methods to make up for the flaws of each method and incorporate long-term monitoring.

Lessons learned implementing mineral accretion and coral gardening at Agincourt Reef, Great Barrier Reef

SummaryThe health and diversity of coral reefs are critically important to the stability and value of the marine tourism industry. Declines in coral reef health through climate change impacts and cyclones, and associated media coverage, have impacted tourism visitation. In January 2018, a major change in Australian Government policy included a Reef Restoration and Adaptation Program to investigate the best science and technology options for helping the Great Barrier Reef recover and adapt to the changing environment. We report on a trial of two intervention methods, mineral accretion and coral gardening, to improve hard coral recovery at a popular site on the Great Barrier Reef. We installed six artificial reef substrates onto which an equal number of coral fragments of seven species were transplanted over the course of two years. During this time, three of the six treatments were connected to a low‐voltage power source to encourage mineral accretion and enhance coral growth. Electrolysis resulted in substantial mineral accretion on the steel substrate, however, the technology had no positive effect on the survival or growth of transplanted coral colonies. After 13 months, a second round of transplanted coral fragments was undertaken, and the electrolysis was discontinued. Over a four‐year period, mean live coral cover increased significantly in both treatment locations, from 1.7% and 0% to 80.8% and 75.8%, respectively. Control locations increased insignificantly from a mean of 5% to 14.2%. The mineral accretion technology proved technically challenging and did not support the growth or health of transplanted corals, providing no evidence to support the use of mineral accretion technology for this purpose. The technology may, however, have applications in the creation of new, solid substrates and for initial rubble stabilisation efforts. These results demonstrate the effective use of artificial substrates in conjunction with coral gardening techniques for the recovery of hard coral at degraded tourism sites.

Evaluation of Forsythia suspensa extract for drug therapy of ciliate infection in coral (Goniopora columna)

Coral aquaculture is an emerging aquaculture industry. In recent years, ciliate infestation has become a serious hazard to wild and captive corals. Our previous research found that infected corals can fester or die within 72 h, posing a serious threat to large-scale coral aquaculture. Little research has been done on the treatment of coral ciliate disease. Therefore, drugs that seek effective treatment and avoid stress responses to corals will be applied to large-scale coral aquaculture. Forsythia suspensa is a common traditional Chinese medicine with anti-inflammatory, anticancer, antibacterial, antiviral, and insecticidal functions. In this study, the F. suspensa extract at concentrations of 0.5%, 1%, 1.25%, 1.75%, 2.25%, and 2.75% was used to conduct a virulence test on ciliates and evaluate the therapeutic effect on Goniopora columna. The uninfected ciliates are the N-group, and the infected ciliates without drug treatment, the control group, are the C-group. After the experiment, the effects of the F. suspensa extract on the ciliate stress response of corals were evaluated by using the virulence test and calculating damage to histopathology, zooxanthellae, chlorophyll a, and three antioxidant enzymes, namely, superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA). The results showed that the LC50 value of the F. suspensa extract was approximately 1.52%, and when the concentration was increased to 1.75%, the ciliates could be completely killed within 10 min of medicated bathing. The SOD, CAT, and MDA of G. columna under the 1.75% treatment were lower than those of the other treatment groups and higher than only those of the N-group. The zooxanthellae, chlorophyll a, and survival rate were not significantly different from those in the N-group. Upon histological examination, no ciliates or vacuum were found in coral tissue 72 h after treatment. In conclusion, 1.75% Forsythia suspensa extract is effective in the treatment of G. columna ciliate infection without causing a strong stress response in corals. Forsythia suspensa can be effectively applied in the prevention of ciliate diseases in large-scale coral aquaculture.

Research on Underwater Image Restoration Technology Based on Multi-Domain Translation

Underwater images are crucial in various underwater applications, including marine engineering, underwater robotics, and subsea coral farming. However, obtaining paired data for these images is challenging due to factors such as light absorption and scattering, suspended particles in the water, and camera angles. Underwater image recovery algorithms typically use real unpaired dataset or synthetic paired dataset. However, they often encounter image quality issues and noise labeling problems that can affect algorithm performance. To address these challenges and further improve the quality of underwater image restoration, this work proposes a multi-domain translation method based on domain partitioning. Firstly, this paper proposes an improved confidence estimation algorithm, which uses the number of times a sample is correctly predicted in a continuous period as a confidence estimate. The confidence value estimates are sorted and compared with the real probability to continuously optimize the confidence estimation and improve the classification performance of the algorithm. Secondly, a U-net structure is used to construct the underwater image restoration network, which can learn the relationship between the two domains. The discriminator uses full convolution to improve the performance of the discriminator by outputting the true and false images along with the category to which the true image belongs. Finally, the improved confidence estimation algorithm is combined with the discriminator in the image restoration network to invert the labels for images with low confidence values in the clean domain as images in the degraded domain. The next step of image restoration is then performed based on the new dataset that is divided. In this way, the multi-domain conversion of underwater images is achieved, which helps in the recovery of underwater images. Experimental results show that the proposed method effectively improves the quality and quantity of the images.

Optimizing facility location, sizing, and growth time for a cultivated resource: A case study in coral aquaculture.

Production of cultivated resources require additional planning that takes growth time into account. We formulate a mathematical programming model to determine the optimal location and sizing of growth facilities, impacted by resource survival rate as a function of its growth time. Our method informs strategic decisions regarding the number, location, and sizing of facilities, as well as operational decisions of optimal growth time for a cultivated resource in a facility to minimize total costs. We solve this facility location and sizing problem in the context of coral aquaculture for large-scale reef restoration using a two-stage algorithm and a linear mixed-integer solver. We assess growth time in a facility in terms of its impact on survival (post-deployment) considering growth quantity requirements and growth facility production constraints. We explore the sensitivity of optimal facility number, location, and sizing to changes in the geographic distribution of demand and cost parameters computationally. Results show that the relationship between growth time and survival is critical to optimizing operational decisions for grown resources. These results inform the value of data certainty to optimize the logistics of coral aquaculture production.