National Committee on Marine Sciences (NCMS)
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- Comparison of photosynthetic responses of healthy and ‘diseased’ Kappaphycus alvarezii (Doty) Doty using P vs I curveGanzon-Fortes, E. T.; Azanza-Corrales, R.; Aliaza, T. (Walter de Gruyter GmbH, 1993)Healthy and 'diseased' thalli of Kappaphycus alvarezii were collected from two different sites in Bolinao, Pangasinan, northern Philippines. Their photosynthetic responses to varying photon fluence levels we reassessed. The healthy branches had higher photosynthetic rates (expressed in mgO2 gdw"1 h'1) at all light levels and did not show photoinhibition at photon fluence levels of up to 800 μπιοί photons m~2s~!. The 'diseased' branches showed a significant decrease in their photosynthetic performance as manifested by their lower Pmax, increased Ic, and lower alpha, and a photoinhibition above 600 μιηοΐ photons m~2 s"1. Examination of the concentration of pigments — chlorophyll a, r-phycoerythrin and r-phycocyanin, revealed a significant drop in the 'diseased' plants, suggesting the major role played by these pigments in the observed differences in their photosynthetic responses.
- Feeding ecology and trophic role of sea urchins in a tropical seagrass communityKlumpp, David W.; Salita-Espinosa, J. T.; Fortes, M. D. (Elsevier BV, 1993-04)The grazing impact of urchins on seagrass and algal resources, and the relative importance of this to the lower-level trophic flux of a tropical seagrass community were investigated. Thalassia hemprichii (Ehrenb.) Aschers. accounted for 80–93% of seagrass frond biomass at Bolinao in the Philippines. Growth rate of seagrass was 6.6 mm per shoot day−1, or 2.3 mg AFDW per shoot day−1. Production of seagrass fronds per unit area of seagrass bed varied with location from 870 to 1850 mg AFDW m−2 day−1. Urchin density ranged from 0.9 to 4.2 m−2, with Tripneustes gratilla (L.) and Salmacis sphaeroides (L.) being the most common species. Tripneustes gratilla fed mostly on attached seagrass fronds (77–89% of diet), especially Thalassia hemprichii, whereas S. sphaeroides was a generalist, consuming Thalassia hemprichii fronds (13–65%), detached seagrass debris (5–39%), the red alga Amphiroa fragilissima (L.) Lamour. (0–30%), algal-coated sediment and rubble (0–51%) in proportions that varied with the availability of preferred food types. Live Thalassia hemprichii fronds were clearly preferred over macroalgae or dead seagrass fronds by Tripneustes gratilla, but S. sphaeroides consumed all three food types without preference. Both urchins avoided the common brown alga, Sargassum crassifolium J. Agardh. Urchins absorbed 73–76% of organic matter in seagrass fronds with epiphytes (75% of DW), and 55% of that in epiphyte-free fronds. Seagrass debris and the macroalgae A. fragilissima were of lower food quality as they were lower in organic matter, and this matter was absorbed less efficiently by urchins. Rates of ingestion (IR in g WW per urchin day−1) were proportional to body weight (W in g WW) according to the functions: IR = 0.56W0.34 (T. gratilla) and IR = 0.17W0.53 (Salmacis sphaeroides). Predicted grazing impact of urchins on seagrass resources varied spatially and temporally. Estimated annual grazing rate at the main study site was 158 g AFDW m−2, equivalent to 24% of annual seagrass production, but owing to large changes in urchin population structure and density, grazing impact is expected to vary from < 5% to > 100% at different times of year. A synthesis of knowledge on the lower-level trophic pathways in this system indicates that seagrass-urchin and periphyton-epifauna grazing interactions are both important in their contribution to overall trophic flux.
- Wound healing in cultured Eucheuma alvareziivar. tambalang DotyAzanza-Corrales, R.; Dawes, C. J. (Walter de Gruyter GmbH, 1989)Wound healing in segments of Eucheuma alvarezii var. tambalang grown in enriched media in the laboratory can be divided into four stages based on histological and cytological changes. During the first stage, approximately 2—4 days after wounding, proteinaceous and phenolic substances concentrate on pit plugs of cells adjacent to the wounded surface. In the second stage, about the sixth day, cellular extensions are produced from the pits of medullary and cortical cells of sub-wound layer. During the third stage, about the 8th day, the cellular extensions divide several times and elongate towards the surface. A new cortical or wound tissue is formed during the fourth stage beginning on the 12th day. The wound tissue is continuous with the old cortex within 3 weeks.
- Seasonality of standing crop of a Sargassum (Fucales, Phaeophyta) bed in Bolinao, Pangasinan, PhilippinesTrono, Gavino C.; Lluisma, Arturo O. (Springer, 1990-09)The seasonality of standing crop of a Sargassum bed was investigated by conducting monthly sampling from February 1988 to July 1989. Environmental parameters of water movement, salinity, number of daytime minus tides, and water temperature were also measured. An intra-annual pattern of variation in standing crop of Sargassum crassifolium, S. cristaefolium, S. oligocystum, and S. polycystum was observed. Standing crop was generally lowest in February, March, April, or May, and highest in November through January. Sargassum accounted for about 35 to 85% of the monthly algal standing crop of the bed, and the observed variation in overall standing crop of the bed generally reflected the standing crop of Sargassum. The seasonality of the standing crops of the associated algal divisions also followed an annual cycle, but their maximum and minimum standing crops did not coincide with those of Sargassum. Individually, as well as collectively, the standing crops of the Sargassum spp. were poorly correlated with the environmental factors observed.
- La Union board declares calamity state to deal with oil spillSotelo, Yolanda (Philippine Daily Inquirer, Inc., 2013-03-01)The provincial board of La Union has declared the province under a state of calamity to enable towns affected by the oil spill supposedly from a sunken vessel or another ship to tap their calamity funds for cleanup operations. La Union Gov. Manuel Ortega said communities, various agencies and nongovernment organizations have been collaborating to remove chunks of hardened oil that have been spotted on La Union beaches. Many believe the oil sludge came from the Myanmar vessel MV Harita Bauxite, which sank off Bolinao town in Pangasinan last week. Others suspect it came from an unidentified cargo vessel, which docked near Bangar town in La Union, on Sunday.