Challenge 06: Increase community resilience to ocean hazards
Permanent URI for this collectionhttps://repository.unesco.gov.ph/handle/123456789/25
Ocean Decade
Challenge 06:
Increase community resilience to ocean hazards
Enhance multi-hazard early warning services for all geophysical, ecological, biological, weather, climate and anthropogenic related ocean and coastal hazards, and mainstream community preparedness and resilience.
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- Elevated seawater temperatures affect embryonic and larval development in the giant clam Tridacna gigas (Cardiidae: Tridacninae)Enricuso, Odette B.; Conaco, Cecilia; Sayco, Sherry Lyn G.; Neo, Mei Lin; Cabaitan, Patrick (Oxford Academic, 2018-11-17)Giant clams are the largest bivalve molluscs and play a key role in coral reef ecosystems. Almost all species are considered endangered or vulnerable to extinction, thus requiring intervention through culturing and restocking. Although successful culture techniques have been developed, the responses of giant clam embryos and larvae to environmental factors, such as seawater temperature, are not yet fully understood. In this study, fertilization, development and survival of Tridacna gigas larvae were observed at low (28 °C), medium (30 °C) and high (33 °C) seawater temperatures. Fertilization success was not significantly different between the water temperatures tested. At 28 °C, ciliated gastrulae appeared first at 12 h postfertilization (hpf) and trochophore larvae at 24 hpf. In contrast, more rapid development was observed at 30 °C and 33 °C, with ciliated gastrulae first appearing at 9 hpf and trochophore larvae at 18 hpf. Veliger larvae were observed after 48 h at 28 °C and 30 °C. No veligers were observed at 33 °C, but a greater proportion of embryos and larvae exhibited developmental abnormalities at this temperature compared with the other treatments. Larval survival was lowest at 33 °C at the 12 and 24 h timepoints, although there was no longer a significant difference across treatments after 48 h. Furthermore, post-settlement survival of juveniles subjected to different seawater temperatures for 22 d starting at 8 d postfertilization (dpf) was lowest at 33 °C. These findings reveal that higher water temperatures promote rapid progression through early development, but result in lower overall survival as a consequence of abnormal development and reduced post-settlement survival.The authors acknowledge Julio Curiano and the staff of the Bolinao Marine Laboratory for assistance with experiments. This work was supported in part by the University of the Philippines Marine Science Institute; a grant from the National Geographic Society (ASIA-08-15) to PCC; a grant from the Department of Science and Technology Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (QMSR-MRRD-MEC-295-1449) to PCC and CC; and a Department of Science and Technology Science Education Institute graduate scholarship to OBE. MLN acknowledges the support of the National Research Foundation Singapore for research at the St John’s Island National Marine Laboratory.
- The Philippine shipbuilding and ship repair industry situation report 1997Maritime Industry Authority (Philippine Council for Aquatic and Marine Research and Development, 2002)This report presents a comprehensive overview of the Philippine shipbuilding and ship repair (SBSR) industry as of 1997, prepared by the Maritime Industry Authority (MARINA). As an archipelagic nation dependent on maritime transport for 95% of its cargo and passenger movement, the Philippines requires a strong SBSR sector to support its domestic and international fleet. The report details the industry’s profile, including 253 licensed enterprises with facilities concentrated in Luzon, Visayas, and Mindanao, and a workforce of nearly 35,000 skilled and technical personnel. It highlights the dominance of foreign-assisted large shipyards, the rise of ship construction for both domestic use and export, and the central role of ship repair activities due to regulatory requirements and regional demand. Issues such as low local demand for newbuildings, reliance on imported secondhand ships, inadequate ancillary industries, outdated facilities, and manpower challenges are discussed. Government policies, investment incentives, and private sector initiatives are outlined to address these constraints. Finally, the report emphasizes growth prospects in shipbuilding, repair, and shipbreaking, underscoring the industry’s potential to achieve international competitiveness through modernization, foreign partnerships, and research and development.
- The mapping of storm surge-prone areas and characterizing surge-producing cyclones in Leyte Gulf, PhilippinesRodrigo, Soccoro Margarita T.; Villanoy, Cesar L.; Briones, Jeric C.; Bilgera, Princess Hope T.; Cabrera, Olivia C.; Narisma, Gemma Teresa T. (Springer Nature Link, 2018-03-15)Historically, Leyte Gulf in central eastern Philippines has received catastrophic damage due to storm surges, the most recent of which was during Typhoon Haiyan in 2013. A city-level risk assessment was performed on Leyte Gulf through synthetic storm generation, high-resolution ocean modeling, and decision tree analyses. Cyclones were generated through a combination of a Poisson point process and Monte Carlo simulations. Wind and pressure fields generated from the cyclones were used in a storm surge model of Leyte Gulf developed on Delft3D. The output of these simulations was a synthetic record of extreme sea level events, which were used to estimate maximum surge heights for different return periods and to characterize surge-producing storm characteristics using decision tree analyses. The results showed that the area most prone to surges is the Tacloban–Basey area with a 2.8 ± 0.3 m surge occurring at a frequency of every 50 years. Nearby Palo area will likely receive a surge of 1.9 ± 0.4 m every 50 years while Giporlos–Salcedo area a surge of 1.0 ± 0.1 m. The decision tree analysis performed for each of these areas showed that for surges of 3–4 m, high-velocity winds (> 30 m/s) are consistently the main determining factor. For the areas, Tacloban, Basey, and Giporlos–Salcedo, wind speed was also the main determining factor for surge > 4 m.Funding was provided by the Philippine Council for Agriculture, Aquatic, and Natural Resources Research and Development, Department of Science and Technology (DOST-PCAARRD). We thank the reviewers for their helpful comments and suggestions.
- Sponge-microbe partnerships are stable under eutrophication pressure from maricultureBaquiran, Jake Ivan P; Conaco, Cecilia (Elsevier, 2018-11)Sponges harbor a great diversity of symbiotic microorganisms. However, environmental stresses can affect this partnership and influence the health and abundance of the host sponges. In Bolinao, Pangasinan, Philippines, chronic input of organic materials from mariculture activities contributes to a eutrophic coastal environment. To understand how these conditions might affect sponge-microbial partnerships, transplantation experiments were conducted with the marine sponge Gelliodes obtusa. High-throughput sequencing of 16S rRNA revealed that the associated microbial community of the sponges did not exhibit significant shifts after six weeks of transplantation at a eutrophic fish farm site compared to sponges grown at a coral reef or a seagrass area. However, sponges at the fish farm revealed higher abundance of the amoA gene, suggesting that microbiome members are responsive to increased ammonium levels at the site. The stable association between G. obtusa and its microbiome indicates that the sponge holobiont can withstand eutrophication pressure from mariculture.
- Fisheries Administrative Order No. 156: Series of 1986. Guidelines and Procedures in the Effective Implementation of LOI No. 1328.(Department of Agriculture, 1986-07-03)
- Endosymbiotic dinoflagellates pump iron: differences in iron and other trace metal needs among the SymbiodiniaceaeReich, Hannah G.; Rodriguez, Irene B.; LaJeunesse, Todd C.; Ho, Tung-Yuan (Springer, 2020-03-06)Iron (Fe) is essential to the physiology and growth of marine phytoplankton. It remains unclear how important iron is to the functional ecology of symbiotic dinoflagellates in the family Symbiodiniaceae, and whether limitations in iron ultimately affect the health and productivity of coral hosts, especially during episodes of ocean warming. Five Symbiodiniaceae species (spanning three genera) were used to investigate the effects of reduced iron availability on cell growth and the acquisition of other trace metals. When grown under iron replete conditions, intracellular iron quotas (content) reflected a large biochemical demand and ranged from 7.8 to 23.1 mmol Fe mol Phosphorus−1. Symbiodinium necroappetens was the only species that acclimated and maintained high growth rates while subjected to the lowest iron treatment (250 pM Fe′). Cultures surviving under low iron concentrations experienced changes in cellular concentrations (and presumably their use as cofactors) of other trace metals (e.g., zinc, copper, cobalt, manganese, nickel, molybdenum, vanadium), in ways that were species-specific, and possibly related to the natural ecology of each species. These changes in trace metal contents may have cascading effects on vital biochemical functions such as metalloenzyme activities, photosynthetic performance, and macronutrient assimilation. Furthermore, these species-specific responses to iron limitation provide a basis for investigations on how iron availability effects cellular processes among species and genera of Symbiodiniaceae, and ultimately how metal shortages modulate the response of coral–algal mutualisms to physiological stressors.The authors thank Jie-Cheng Chang, Wan-Yen Cheng, and Wan-Chen Tu for technical support. This work was funded by NSF-EAPSI and MOST #1713926 (to HGR), NASA PA Space Grant Fellowship (to HGR), NSF-BIO-OCE #1636022 (to TCL), MOST 106-2611-M-001-003 (to TYH), MOST 107-2611-M-001-001 (to TYH), and Academia Sinica Career Development Award (to TYH). We are grateful to the two anonymous reviewers whose comments improved the quality of the paper.
- Heat stress responses and population genetics of the kelp Laminaria digitata (Phaeophyceae) across latitudes reveal differentiation among North Atlantic populationsLiesner, Daniel; Fouqueau, Louise; Valero, Myriam; Roleda, Michael Y.; Pearson, Gareth A.; Bischof, Kai; Valentin, Klaus; Bartsch, Inka (Wiley, 2020-08-17)To understand the thermal plasticity of a coastal foundation species across its latitudinal distribution, we assess physiological responses to high temperature stress in the kelp Laminaria digitata in combination with population genetic characteristics and relate heat resilience to genetic features and phylogeography. We hypothesize that populations from Arctic and cold-temperate locations are less heat resilient than populations from warm distributional edges. Using meristems of natural L. digitata populations from six locations ranging between Kongsfjorden, Spitsbergen (79°N), and Quiberon, France (47°N), we performed a common-garden heat stress experiment applying 15°C to 23°C over eight days. We assessed growth, photosynthetic quantum yield, carbon and nitrogen storage, and xanthophyll pigment contents as response traits. Population connectivity and genetic diversity were analyzed with microsatellite markers. Results from the heat stress experiment suggest that the upper temperature limit of L. digitata is nearly identical across its distribution range, but subtle differences in growth and stress responses were revealed for three populations from the species’ ecological range margins. Two populations at the species’ warm distribution limit showed higher temperature tolerance compared to other populations in growth at 19°C and recovery from 21°C (Quiberon, France), and photosynthetic quantum yield and xanthophyll pigment responses at 23°C (Helgoland, Germany). In L. digitata from the northernmost population (Spitsbergen, Norway), quantum yield indicated the highest heat sensitivity. Microsatellite genotyping revealed all sampled populations to be genetically distinct, with a strong hierarchical structure between southern and northern clades. Genetic diversity was lowest in the isolated population of the North Sea island of Helgoland and highest in Roscoff in the English Channel. All together, these results support the hypothesis of moderate local differentiation across L. digitata's European distribution, whereas effects are likely too weak to ameliorate the species’ capacity to withstand ocean warming and marine heatwaves at the southern range edge.
- Molecular phylogeny of three unarmored dinoflagellates from Masinloc Bay, Zambales, Central Luzon, with a description of the morphology of Gymnodinium catenatum H.W.GrahamBenico, Garry; Azanza, Rhodora (Science and Technology Information Institute, 2021-10-27)Unambiguous identification of unarmored dinoflagellates is important in distinguishing toxic from non-toxic species occurring in the coastal waters of the Philippines. In this study, molecular phylogeny inferred from rDNA sequences of Gymnodinium catenatum, Gymnodinium impudicum, and Akashiwo sanguinea-collected from Masinloc Bay, Zambales, Central Luzon-is reported for the first time. Morphology of G. catenatum was critically examined using light and confocal laser scanning microscopy. The three unarmored dinoflagellates were identified as G. catenatum, G. impudicum, and A. sanguinea based on their phylogenetic positions inferred from LSU and SSU rDNA. Both G. catenatum and G. impudicum grouped in a well-supported clade of Gymnodinium sensu stricto, which includes other genera of unarmored dinoflagellates, confirming the polyphyly of the clade. Akashiwo sanguinea separated into four subclades, which is similar to previous reports-with our strain grouping with sequences from Malaysia, Singapore, and China. Cellular characteristics of our G. catenatum are congruent with earlier reports particularly its long chain-forming habit (up to 64 cells) and large cell size (44.6-63.3 µm long). Our result is the first verified record of G. impudicum and A. sanguinea in the Philippines, and the first record of G. catenatum as another highly toxic dinoflagellate species occurring in Masinloc Bay.
- Low coral bleaching prevalence at the Bolinao-Anda Reef Complex, northwestern Philippines during the 2016 thermal stress eventQuimpo, Timothy Joseph R.; Requilme, Jeremiah Noelle C.; Gomez, Elizabeth J.; Sayco, Sherry Lyn G.; Tolentino, Mark Paulo S.; Cabaitan, Patrick C. (Elsevier BV, 2020-11)Here, we examined the coral bleaching responses during the 2016 thermal stress event and post-bleaching changes in coral communities in the heavily disturbed reefs of the Bolinao-Anda Reef Complex (BARC), northwestern Philippines. Less than 25% of colonies bleached, with 77% attributed to five genera (Dipsastrea, Porites, Fungia, Seriatopora, and Montipora). Coral bleaching prevalence was associated with site location, coral composition, and coral abundance, suggesting that small-scale variation (<20 km) in coral communities (taxa and density) influences spatial variation in coral bleaching prevalence. There was no noticeable change in coral composition and cover two years after the bleaching event as exposure to chronic disturbance likely selected for the dominance of stress tolerant coral taxa and communities. Results show that the 2016 thermal stress event caused coral bleaching but with low prevalence at the BARC, which suggests that disturbed reefs may provide spatial refuge to coral communities from thermal stress.We acknowledge M Ponce, F Castrence, R de Guzman, G de Guzman, R Adolfo, and R Uriarte for the field assistance; and boatmen and administration from the Bolinao Marine Laboratory of the UPMSI (University of the Philippines Marine Science Institute) for their valuable assistance in the logistics and field works. We are grateful to R Dizon for kindly reading and providing suggestions that improved the manuscript. This study was funded by the OVCRD (Office of the Vice Chancellor for Research and Development) Outright Research Grant (Project No. 161607 PNSE) and the Marine Science Institue In-house Research Grant of the University of the Philippines; and grants from the Philippine Council for Agriculture, Aquatic, and Natural Resources Research and Development of the Department of Science and Technology (QMSR-MRRD-MEC-295-1449 and QMSR-MRRD-MEC314-1542) of PC Cabaitan.
- Expanding ocean food production under climate changeFree, Christopher M.; Cabral, Reniel B.; Froehlich, Halley E.; Battista, Willow; Ojea, Elena; O’Reilly, Erin; Palardy, James E.; García Molinos, Jorge; Siegel, Katherine J.; Arnason, Ragnar; Juinio–Meñez, Marie Antonette; Fabricius, Katharina; Turley, Carol; Gaines, Steven D. (Springer, 2022-04-27)As the human population and demand for food grow, the ocean will be called on to provide increasing amounts of seafood. Although fisheries reforms and advances in offshore aquaculture (hereafter ‘mariculture’) could increase production, the true future of seafood depends on human responses to climate change. Here we investigated whether coordinated reforms in fisheries and mariculture could increase seafood production per capita under climate change. We find that climate-adaptive fisheries reforms will be necessary but insufficient to maintain global seafood production per capita, even with aggressive reductions in greenhouse-gas emissions. However, the potential for sustainable mariculture to increase seafood per capita is vast and could increase seafood production per capita under all but the most severe emissions scenario. These increases are contingent on fisheries reforms, continued advances in feed technology and the establishment of effective mariculture governance and best practices. Furthermore, dramatically curbing emissions is essential for reducing inequities, increasing reform efficacy and mitigating risks unaccounted for in our analysis. Although climate change will challenge the ocean’s ability to meet growing food demands, the ocean could produce more food than it does currently through swift and ambitious action to reduce emissions, reform capture fisheries and expand sustainable mariculture operations.