Journal Articles - UP - MSI
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- 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.
- Effect of the Intensified Sub‐Thermocline Eddy on strengthening the Mindanao undercurrent in 2019Azminuddin, Fuad; Lee, Jae Hak; Jeon, Dongchull; Shin, Chang‐Woong; Villanoy, Cesar; Lee, Seok; Min, Hong Sik; Kim, Dong Guk (American Geophysical Union, 2022-02)The northward-flowing Mindanao Undercurrent (MUC) was directly measured by acoustic Doppler current profilers from a subsurface mooring at about 8°N, 127°E during 2 years (November 2017–December 2019). Its depth covers a range from 400 m to deeper than 1,000 m with its core appearing at around 900 m. The mean velocity of MUC's core was approximately 5.8 cm s−1 with a maximum speed of about 47.6 cm s−1. The MUC was observed as a quasi-permanent current with strong intraseasonal variability (ISV) with a period of 70–80 days. Further analyses with an eddy-resolving circulation model output suggest that the ISV is closely related to sub-thermocline eddies (SEs). In this study, two types of SEs near the Philippine coast are disclosed: the westward propagating SE (SE-1) and the quasi-stational SE southeast of Mindanao Island (SE-2). The SE-1 has both cyclonic and anticyclonic polarities with the propagation speed of 7–8 cm s−1, while the SE-2 is an anticyclonic eddy that moves erratically within 4–8°N, 127–130°E with the mean translation speed of about 11 cm s−1. Even though the SE-1 plays an important role in modulating the MUC, our results show that the observed strong MUC event (May–July 2019) is evidently induced by the intensified SE-2 that moves northwestward. This study emphasizes that the SE-2 when intensified, receives more energy from the strengthened New Guinea Coastal Undercurrent and loses the energy northward along the Philippine coast by intensifying the MUC.This study was part of the project entitled “study on air–sea interaction and process of rapidly intensifying Typhoon in the northwestern Pacific” (PM61670) funded by the Ministry of Oceans and Fisheries, Rep. of Korea. This study was also partly supported by the project entitled “Influences of the Northwest Pacific circulation and climate variability on the Korean water changes and material cycle I—The role of Jeju warm current and its variability” (PEA0011) funded by Korea Institute of Ocean Science and Technology (KIOST). The mooring data used in this study were provided by KIOST and are available from the KIOST live access server (http://las.kiost.ac.kr/data_adcp/). The model data are freely available from Mercator Ocean (https://resources.marine.copernicus.eu/?option=com_csw&view=details&product_id=GLOBAL_ANALYSIS_FORECAST_PHY_001_024).
- Through the boundaries: Environmental factors affecting reef benthic cover in marine protected areas in the PhilippinesPanga, Fleurdeliz M.; Anticamara, Jonathan A.; Quibilan, Miledel Christine C.; Atrigenio, Michael P.; Aliño, Porfirio M. (Frontiers Media SA, 2021-08-18)Philippine coral reefs have been on the decline since the 1970s, and this degradation has posed a risk to biodiversity, food security, and livelihood in the country. In an effort to arrest this degradation, marine protected areas (MPAs) were established across the country. MPAs are known to improve fish biomass, but their effect on live coral cover and other benthos is not yet well documented and understood. In this study, 28 MPAs across the Philippines were surveyed comparing benthic cover and indices between protected reefs and adjacent unprotected reefs. No consistent differences were found between reefs inside and outside MPAs through all the benthic categories and reef health indices considered that are indicative of protection effects or recovery within MPAs. However, there were notable site-specific differences in benthic cover across the study MPAs-suggesting that factors other than protection play important roles in influencing benthic cover inside and outside of MPAs. Storm frequency and proximity to rivers, as a proxy for siltation, were the strongest negative correlates to live coral cover. Also, high coastal population, a proxy for pollution, and occurrence of blast and poison fishing positively correlated with high dead coral cover. The lack of significant difference in benthic cover between reefs inside and outside MPAs suggests that protection does not necessarily guarantee immediate improvement in benthic condition. Correlations between benthic condition and storm frequency, siltation, and pollution suggest that it is necessary to augment MPAs with other management strategies that will address the multiple stressors that are usually indiscriminate of MPA boundaries. Supplementing long-term and systematic monitoring of benthic cover and biodiversity inside and outside of MPAs with data on other important environmental and human impact variables will help improve understanding of benthic cover and biodiversity dynamics inside and outside of MPA boundaries.We would like to thank RARE Philippines and USAID, in collaboration with the Marine Environment and Resources Foundation (MERF), for research funding, coordination, and support in the execution of this research. We would also like to thank the RARE Conservation Fellows and Local Government Units for logistical support and coordination on all of the MPAs studied. We would also like to thank the Fisheries team of the MSI Community Laboratory for the municipal profile data, and the MSI Physical Oceanography Laboratory for the storm frequency and relative exposure index used in the environmental correlation. We would also like to thank the rest of the MERF-RARE Team/MSI Community Ecology Laboratory who joined and supported the many months of data gathering, encoding, and data analysis.