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.
Browse
Search Results
- 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.
- Biochemical mapping of Pyrodinium bahamense unveils molecular underpinnings behind organismal processesSubong, Bryan John J.; Malto, Zabrina Bernice L.; Lluisma, Arturo O.; Azanza, Rhodora V.; Salvador-Reyes, Lilibeth A. (MDPI, 2021-12-11)Proteins, lipids, and carbohydrates from the harmful algal bloom (HAB)-causing organism Pyrodinium bahamense were characterized to obtain insights into the biochemical processes in this environmentally relevant dinoflagellate. Shotgun proteomics using label-free quantitation followed by proteome mapping using the P. bahamense transcriptome and translated protein databases of Marinovum algicola, Alexandrium sp., Cylindrospermopsis raciborskii, and Symbiodinium kawagutii for annotation enabled the characterization of the proteins in P. bahamense. The highest number of annotated hits were obtained from M. algicola and highlighted the contribution of microorganisms associated with P. bahamense. Proteins involved in dimethylsulfoniopropionate (DMSP) degradation such as propionyl CoA synthethase and acryloyl-CoA reductase were identified, suggesting the DMSP cleavage pathway as the preferred route in this dinoflagellate. Most of the annotated proteins were involved in amino acid biosynthesis and carbohydrate degradation and metabolism, indicating the active roles of these molecules in the vegetative stage of P. bahamense. This characterization provides baseline information on the cellular machinery and the molecular basis of the ecophysiology of P. bahamense.
- 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.
- Precipitation stable isotopic signatures of tropical cyclones in Metropolitan Manila, Philippines, show significant negative isotopic excursionsJackisch, Dominik; Yeo, Bi Xuan; Switzer, Adam D.; He, Shaoneng; Cantarero, Danica Linda M.; Siringan, Fernando P.; Goodkin, Nathalie F. (Copernicus GmbH, 2022-01-28)Tropical cyclones have devastating impacts on the environment, economies, and societies and may intensify in the coming decades due to climate change. Stable water isotopes serve as tracers of the hydrological cycle, as isotope fractionation processes leave distinct precipitation isotopic signatures. Here we present a record of daily precipitation isotope measurements from March 2014 to October 2015 for Metropolitan Manila, a first-of-a-kind dataset for the Philippines and Southeast Asia. We show that precipitation isotopic variation at our study site is closely related to tropical cyclones. The most negative shift in δ18O values (−13.84 ‰) leading to a clear isotopic signal was caused by Typhoon Rammasun, which directly hit Metropolitan Manila. The average δ18O value of precipitation associated with tropical cyclones is −10.24 ‰, whereas the mean isotopic value for rainfall associated with non-cyclone events is −5.29 ‰. Further, the closer the storm track is to the sampling site, the more negative the isotopic values are, indicating that in situ isotope measurements can provide a direct linkage between isotopes and typhoon activities in the Philippines.This research was supported by the Earth Observatory of Singapore (EOS) via its funding from the National Research Foundation Singapore and the Ministry of Education of Singapore under the Research Centres of Excellence initiative. This work comprises EOS contribution no. 422. This study is also the part of the IAEA Coordinated Research Project (CRP code: F31004) on “Stable Isotopes in Precipitation and Paleoclimatic Archives in Tropical Areas to Improve Regional Hydrological and Climatic Impact Models” (IAEA Research Agreement no. 17980).
- Summer heatwave impacts on the European kelp Saccharina latissima across its latitudinal distribution gradientDiehl, Nora; Roleda, Michael Y.; Bartsch, Inka; Karsten, Ulf; Bischof, Kai (Frontiers Media SA, 2021-10-11)Kelps are important foundation species in coastal ecosystems currently experiencing pronounced shifts in their distribution patterns caused by ocean warming. While some populations found at species’ warm distribution edges have been recently observed to decline, expansions of some species have been recorded at their cold distribution edges. Reduced population resilience can contribute to kelp habitat loss, hence, understanding intraspecific variations in physiological responses across a species’ latitudinal distribution is crucial for its conservation. To investigate potential local responses of the broadly distributed kelp Saccharina latissima to marine heatwaves in summer, we collected sporophytes from five locations in Europe (Spitsbergen, Bodø, Bergen, Helgoland, Locmariaquer), including populations exposed to the coldest and warmest local temperature regimes. Meristematic tissue from sporophytes was subjected to increasing temperatures of Δ+2, Δ+4 and Δ+6°C above the respective mean summer temperatures (control, Δ±0°C) characteristic for each site. Survival and corresponding physiological and biochemical traits were analyzed. Vitality (optimum quantum yield, Fv/Fm) and growth were monitored over time and biochemical responses were measured at the end of the experiment. Growth was highest in northern and lowest in southern populations. Overall, northern populations from Spitsbergen, Bodø and Bergen were largely unaffected by increasing summer temperatures up to Δ+6°C. Conversely, sporophytes from Helgoland and Locmariaquer were markedly stressed at Δ+6°C: occurrence of tissue necrosis, reduced Fv/Fm, and a significantly elevated de-epoxidation state of the xanthophyll cycle (DPS). The variations in phlorotannins, mannitol and tissue C and N contents were independent of temperature treatments and latitudinal distribution pattern. Pronounced site-specific variability in response to increasing temperatures implies that exceeding a threshold above the mean summer temperature exclusively affect rear-edge (southernmost) populations.Abiotic temperature data used in this manuscript were produced with the Giovanni online data system, developed and maintained by the NASA GES DISC. Sampling in France was conducted in accordance with the French legislation on the Access to Genetic Resources and Benefit-Sharing. We also acknowledge the MODIS mission scientists and associated NASA personnel for the production of the data used in this research effort. This study has been conducted at the Alfred Wegener Institute for Polar and Marine Research (AWI), Bremerhaven and at the AWIPEV Research Station in Ny-Ålesund, Svalbard. We are grateful to the station staff of AWIPEV for support and logistics and to the scientific diving teams on Spitsbergen and Helgoland for sampling. We thank A. Wagner (AWI) for sampling support on Helgoland and his support in the setting up of the experiments, and also J. Müller (University of Rostock) for running the C:N analyzer. B. Meyer-Schlosser (University of Bremen) supported sampling and pigment analyses.
- C30 — A simple, rapid, scientifically valid, and low-cost method for citizen-scientists to monitor coral reefsLicuanan, Wilfredo Y.; Mordeno, Princess Zyrlyn B.; Go, Marco V. (Elsevier, 2021-09)The extent and speed of recent changes in reef coral abundances due to ocean warming and human impacts require more widespread capability to map and measure these changes, especially in countries like the Philippines. We present “C30”, a simple, rapid, scientifically valid, and low-cost method for skin divers or freedivers to take random photo-quadrat images within predefined stations on the upper reef slope. C30 yields coral cover data similar to those collected using the more intensive C5 method and can be as powerful in detecting small differences in reef cover. Less time is also needed for training personnel and sampling. However, more photo-quadrat images, better cameras, and closer collaboration with local scientists are required if higher precision data and estimates of coral diversity are needed from C30. C30 is a valuable tool for participatory, community-based citizen science monitoring of coral reefs.We thank the Department of Science and TechnologyPhilippine Council for Agriculture, Aquatic and Natural Resources Research and Development (QMSR-MRRD-COR-0-1209 and PCAARRD-GIA 4478), and the Department of Environment and Natural Resources Coral Reef Visualization and Assessment, The Philippines Project for funding some of the fieldwork. The initial research on citizen-science monitoring was undertaken with funding from Oscar M. Lopez Center for Climate Change Adaptation and Disaster Risk Management Foundation, Inc., The Philippines (Grant number OMLC RG 2017-18). We also thank the DLSU Innovation and Technology Office for the patent application for the C30 monopod in the Intellectual Property Office of the Philippines. The comments and suggestions of the reviewers are acknowledged and are very much appreciated. WY Licuanan is the holder of the Br H Alfred Shields FSC Professorial Chair in Biology and Br Cresentius Richard Duerr FSC Professorial Chair in Biochemistry.
- Characterization of Alexandrium tamutum (Dinophyceae) isolated from Philippine waters, with the rare detection of paralytic shellfish toxinBenico, Garry; Azanza, Rhodora (Association of Systematic Biologists of the Philippines, 2022-04-01)Alexandrium tamutum M.Montressor, A.Beran & U.John is a non-toxic, bloom-forming dinoflagellate species commonly reported in temperate waters. In this study, 8 cultures of A. tamutum established from Bolinao Channel and Manila Bay, Philippines were characterized in terms of their morphology, phylogeny and toxicity. Cells were roundish, measuring 25.5 –29.84 µm long and 26.2–28.45 µm wide. The nucleus is equatorially elongated and located at the center of the cell. The chloroplasts are numerous, golden brown in color and radially arranged. Thecal tabulation is typical of Alexandrium: APC, 4', 6'', 6c, 6s, 5''', 2''''. Shape of the taxonomically informative thecal plates such as sixth precingular plate (6'') and posterior sulcal plate (sp) was similar to A. tamutum, which confirms the species identity. However, the presence of anterior and posterior attachment pores observed in our cultured isolates is the first case in this species. Molecular phylogeny inferred from LSU rDNA and ITS supports our identification by forming a well-supported clade composed of A. tamutum strains from other geographic regions. HPLC analysis showed that A. tamutum is generally non-toxic except for strain ATC9 which has low amount of decarbamoylsaxitoxin (dcSTX), resulting to a toxicity of 0.07 fmole STX eq per cell. The present study reports the first verified occurrence of Philippine A. tamutum with reliable morphological and molecular information, including the first record in Manila Bay and first detection of PST in one strain at a certain culture period.We acknowledge the Department of Science and Technology Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (DOST PCAARRD) and the University of the Philippines-The Marine Science Institute (UP-MSI) for the funding support. We are grateful for the assistance of Joshua Vacarizas, Keith Pinto and Jenelyn Mendoza for the molecular and toxicity analyses of the cultures. We also acknowledge Estrelita Flores, Emelita Eugenio and Jayson Orpeza for their assistance during the fieldwork and other logistical support.