UPV Theses and Dissertations
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Item Filtration rate of the marine clam, Kaltelysia sp. at different light intensities and fed with microalgae Isochrysis galbana and Chaetoceros calcitransBravo, Agnes Therese A. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2005-04)Filtration rate of the marine clam, Katelysia with body lengths ranging from 5-6 cm and body weight from 45-65 g were determined by using the indirect method of suspension depletion and monitored by direct algal cell count. The effects of light intensity and algal species on the feeding behavior of the clam were determined. The first treatment involves total darkness where the basins containing the clams were covered with black plastic bag. In the second treatment, the basins with the clams were placed under ordinary light condition (12h light; 12h dark) and in the third treatment, the basins with the clams were positioned under a 20-watt bulb with continuous illumination (24h light). Results showed significant differences in the filtration rates of clams in different light intensities. It showed higher filtration rate in the total darkness treatment (F=0.132555907) followed by the 12h light: 12h dark treatment and lowest at the treatment provided with 24 h illumination. Apparently, illumination affected valve opening and siphon extension of the clam which also affected the filtration rate of Katelysia. Under total darkness treatment, the clams opened their valves and extended their siphons. Hence, there was highest ingestion of algae or filtration in total darkness which showed to be the optimum condition to stimulate or promote feeding. In the algal species preference experiment, the food used were either Isochrysis galbana, Chaetoceros calcitrans , or a mixture of both. Results showed that I. galbana had the highest number of cells ingested by the clams and removed from suspension. This is considered to be the preferred algal species (F=0.119713) followed by a mixture of both, and lowest on the treatment where C. calcitrans was used as food. The preference of the clam on Isochrysis galbana over Chaetoceros calcitrans could be its smaller size based on dry weight.Item Preliminary assessment of forest canopy and seedling condions of mangroves in oil affected areas in Taklong Island National Marine Reserve, GuimarasBenitez, Zaina Lei Licaniel (2007-04)Mangroves are important ecologically and economically in coastal areas in tropica] and sub-tropical areas in the world. However, they continue to be under threat from various human activities either directly or indirectly. The recent oil spill off the coast of southern Guimaras has brought numerous damages to these critical habitats including the mangroves in Taklong Island National Marine Reserve. This study is part of the over all Oil Spill Assessment program conducted by University of the Philippines in the Visayas following the sinking of M.T. Solar 1. This study aimed to determine the effect of oil spill on shoot development as an indicator of health conditions of trees and seedlings of selected mangroves such as Aegiceras floridum, Avicenia marina, Rhizophora apiculata Rhizophora , Rhizophora stylosa, and Sonneratia alba, in Taklong Island National Marine Reserve. Specifically, it aims to determine 1) standing leaves, 2) new leaves, 3) leaf scars of trees and seedlings. Results showed that shoot development among trees were not significantly different between oiled and unoiled sites but closer examination of species response revealed significant differences on standing leaves and new leaves only. Seedling shoot development showed a consistent significant difference among species and between sites. Aegiceras floridum and Sonneratia alba were least affected as shown by the higher number of standing leaves and least number of leaf scar while the Rhizophora spp. and Avicennia marina had the greatest number of leaf scars and least number of standing leaves. Results of this study showed that seedlings are clearly under stress and are more sensitive to oiling than trees although species response also varied individually. While tree species such as the Rhizophora spp. (e.g. R. apiculata, R. stylosa and R. mucronata) appear to be the most sensitive compared with Aegiceras floridum, Avicennia marina and Sonneratia alba. Results of this study will be useful in providing new knowledge on the evaluation of impacts of oil spills on mangroves.Item Abundance, composition and distribution of phytoplankton in Mindoro StraitBayona, Riena Rose M. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2008-04)Phytoplankton in Mindoro Strait, north of Palawan, were investigated from the samples taken last April-May 2007. Twenty stations were selected from over 40 stations surveyed. Samples were collected by filtering 50L of surface waters through 20 micrometer mesh plankton net using a 10L bucket. Phytoplankton assemblage was grouped into four major taxa. Diatoms dominated the area. It recorded the highest mean density of 314.9indivL-1. It was followed by blue green algae that noted a mean density of 165.69indivL-1. The next most abundant was dinoflagellates that recorded a mean density of 51.59indivL-1 and then the group of silicoflagellates. It recoded 35.69indivL-1 mean density. The top three species were Trichodesmium, Thalasiothrix and Isthmia. Protoperidinium represented the dinoflagellates among the top genera while Eutintinnus recorded the highest silicoflagellate. Higher concentrations were found in the midst of the oceanic region where water currents mainly pass. Overall abundance is lower than other nearby waters. This is maybe due to the effect of water currents.Item Survival and growth of the sea cucumber Holothuria scabra (Jaeger) juveniles reared at different dietsBaylon, Basil C. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2009-03)Sea cucumbers are economically important species, with high demand in local and international markets. Overharvesting due to this high demand causes depletion of wild populations of sea cucumbers. Stock enhancement has been resorted to improve the status of natural populations. This will need the development of rearing technology which includes studies on the effects of different diets on sea cucumber juveniles. In this study, the effects of five diets on growth and survival of sea cucumber Holothuria scabra juveniles were compared. The five treatments used were benthic diatoms (Navicula sp.) alone, combination of benthic diatoms and seaweed (Sargassum sp.) extract, seagrass extract alone, combination of benthic diatoms and seagrass (Thalassia sp.) extract, and commercial shrimp feed. Three replicates were used for each treatment. For every replicate. 10 juveniles with body length 1-2 mm were reared in a 3-L culture container with seawater and no sand substrate. Salinity ranged from 32-35 ppt and the temperature from 26-29°C. It was observed that there was a trend of increasing body weight, body length, and body width of juveniles as weeks of culture progressed. After 7 weeks of culture, best weight gain, increase in body length and body width was achieved in juveniles fed with either benthic diatoms alone or combination diet of benthic diatoms and seaweed extract. There was high survival in all feeding treatments except in H. scabra juveniles fed with commercial shrimp feed. The lowest body weight, length and width and lowest survival were consistently obtained from juveniles given commercial shrimp feed.Item Abundance, composition and distribution of phytoplankton in West Central Sulu SeaBria, Jed B. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2008-11)A total of 28 stations were sampled for abundance, composition and distribution of phytoplankton in the West Central Sulu Sea. The samples were taken from 15-30 April 2007. Samples were collected by filtering 50L of surface water through a 20 pm mesh plankton net. A total of 96 phytoplankton genera were identified and were grouped into four major taxa. The overall mean density was 444.6 cells/L. Diatoms were the most abundant, with the mean density of 213.5 cells/L. The most abundant diatom genus was Chaetoceros. Blue-green algae showed the second-highest mean density of 127.6 cells/L. Trichodesmium was the most abundant genus among the two blue-green algae identified. Trichodesmium was also the most abundant genus, comprising 28.1% of all phytoplankton identified. Dinoflagellates and silicoflagellates were ranked third and fourth among the four major taxa with 77.5 cells/L and 28 cells/L, respectively. Protoperidinium was the most abundant dinoflagellate, while Amphorella was the most abundant silicoflagellate. They made up 6.2% and 1.2 % of all phytoplankton identified, respectively. The stations located along the coast of Palawan and near the Tubattaha Reef Marine National Park showed the highest phytoplankton concentrations.Item Floristic composition and diversity of mangroves in selected sites in the province of Antique, Panay Island, Philippines.Balinas, Lucelle V. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2006-03)Mangroves in the Philippines are in constant danger due to innumerable disturbances in the environment. The study endeavored to assess the floristic composition and diversity of the mangroves in the province of Antique through transect and ocular survey in the randomly selected sites throughout the province. Diversity in the region is high with the presence of 3 1 true mangrove species represented by 16 families and 14 genera. The species include Acanthus ebracteatus, A. ilicifolius, and A. volubilis from Family Acanthaceae, Avicennia alba, A. marina. A. officinalis, and A. rhumphiana from Family Avicenniaceae, Camptostemon philippinensis from Family Bombaceae, Lumnitzera littorea and Lumnitzera racemosa from Family Combretaceae, Excoecaria agallocha from Family Euphorbiaceae, Pemphis acidula from Family Lythraceae, Xylocarpus granatum and Xylocarpus moluccensis from Family Meliaceae, Aegiceras corniculatum and Aegiceras floridum from Family Myrsinaceae, Osbornia octodonta of Family Myrtaceae, Nypa fruticans of Family Palmae, Bruguieria cvlindrica. B. gymnorrhiza, and B. sexangula, Ceriops decandra, C. tagal, Rhizophora apiculata. R. mucronata and R. stylosa from Family Rhizophoraceae, Scyphiphora hydrophvllaceae from Family Rubiaceae, Sonneratia alba, S. caseolaris and S. ovata from Family Sonneratiaceae, and Heritiera littoralis from Family Sterculiaceae . The Shannon Index of Diversity used to determine the measure of diversity in the area is correlated with Pielou's Equitability Index for Evenness. The measures of indices showed that diversity and evenness of the mangal area in the province are directly related, with values of 0.73232 and 0.51163, respectively. Caluya showed the highest diversity index of 1.0132, which consisted of 28 species from 13 families and 15 genera, while Bugasong has a relatively low diversity of 0.0486, denoted by 6 species from 4 families and 4 genera. In general, the high variations in the geomorphology of coastal areas in Antique provided a wide range of substrata for colonization of mangroves that contributed to the high species diversity.Item A study on spawning induction of Imbaw Anodontia edentula (Linne, 1758)Bacaro, Teressa Mae D. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2008-03)The mud clam, Anodontia edentula, was induced to spawn using extract from ripe and developing gonads. Clams responded to the spawning stimulus by extension of the foot, swelling and extension of the mantle, swirling of the whole body, rapid opening and closing of the valves, ejecting of white material from the excurrent siphon, and subsequent contraction of the adductor muscles. Successful spawning of all individuals occurred with the use of gonad extract. Developing homogenized extract was not as effective in inducing the broodstock to spawn. Gametes were released through the excurrent siphon located at the posterior end.Item Assessment of heavy metal traces (Copper and lead) in the soft tissue of Oysters Crassostrea virginicaBalboa, Dexter G. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2010-04-05)The bivalve mollusk Crassostrea virginica is abundant in Brgy. Calaparan, Arevalo and Brgy. Bacong, Dumangas; and are widely consumed by the residence as food. Bioaccumulation of Copper and Lead in the soft tissues of C. virginica from Brgy. Calaparan, Arevalo and Brgy. Bacong, Dumangas were measured and checked if they are still within the permissible levels of Copper and Lead in food based on Median International Standards for metals compiled by the Food and Agricultural Organization of the United Nations. Metal concentrations (μg/g) were determined using Flame Atomic Absorption Spectrophotometer. Mean concentrations of the heavy metals in C. virginica from Calaparan, Arevalo- Cu 27.829, Pb 1.2133; Bacong, Dumangas- Cu 57.834, Pb 0.1338. These levels of Copper and Lead in oyster tissue from both sites are within the the range of Median International Standards for metals and are safe for human consumption. Statistical analysis through one- way ANOVA (F > Fcrit, showed significant difference between sites (Fcrit = 18.51282) for Copper (F value, 215.06569) but not for Lead (F value, 2.25151). The study also provided further solid evidence that bivalve like Crassostrea virginica can recover and concentrate environmentally derived and anthropogenic traces of heavy metals.Item Fungal pathogen associated with Rhizophora stylosa: A comparative study between oiled and unoiled sites within Taklong Island National Marine Reserve (TINMAR), Nueva Valencia, GuimarasBalanga-an, Kristoffer (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2009-03)Mangroves, refer to an assemblage of trees and shrubs that inhabit the coastal intertidal zone in tropical and subtropical regions. They help in the soil formation, protection, and stabilization of our coastal environment as well as serve as shelter and breeding grounds for some of our marine organisms. A mangrove habitat represents the borderline between land and sea and is considered as one of the principal places where spilled oil and associated impacts converge. Oil spill threaten mangroves by predisposing the plants to fungal attacks thereby reducing their resistance to stress and diseases. Studies also show that certain fungi species are able to utilize oil in contaminated mangrove species. This study generally aims to compare the fungal population found on the diseased leaves of Rhizophora stylosa between oiled and unoiled sites in the Taklong Island National Marine Reserve (TINMAR). It also aims to isolate, characterize and identify fungi present in diseased leaves of Rhizophora stylosa using potato dextrose agar (PDA) culture media and determine their frequency of occurrence. Leaf samples were collected from two sites in TINMAR, one of which was contaminated by oil and the other one was not. Three trees were selected to represent each of the two sampling sites (oiled and unoiled), and to each of the selected trees, three diseased leaves were collected. The results of this study showed the dominance of some species of fungi namely, Aspergillus (40%), Penicillium (20%), Cladosporium (13.33%), Monilia (6.67%), Mycelia (6.67%), Humicola (6.67%), and Pestalotiopsis (6.67%). Five out of these seven genera were isolated from the unoiled site while six of these were isolated from the oiled site. Generally, the fungal population was observed to be greater in the oiled site than in the unoiled. This preliminary data indicate that R. stylosa might still be undergoing stress due to the remaining components of the spilled oil in the area. However, this can only be resolved by further monitoring.Item Fungal pathogens associated with Sonneratia alba: A comparative study between oiled and unoiled sites within Taklong Island National Marine Reserve (TINMAR), Nueva Valencia, GuimarasAlbacete, May Therese F. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2009-03)Majority of researches on impacts of oil spills on mangroves focused on the immediate post-spill acute effects. However, the persistence of oil in sediments at oil spill sites has been reported in a number of published works. As such, this remaining oil could serve as source of stress to mangroves resulting into the expression of sub-lethal effects such as changes in foliage and canopy, abnormalities in reproductive structures among others. Furthermore, oil in mangroves also has the potential of increasing fungal attacks due to their impairment of natural defense mechanisms such as salt removal from leaves and trunks. Thus, this study was conducted to determine if there was a difference in fungal species composition and frequency of occurrence of fungal population of mangrove leaves collected in oiled and unoiled areas within Taklong Island National Marine Reserve, Nueva Valencia, Guimaras following the spill that occurred in August I1,2006. Fungi from diseased leaves of Sonneratia alba were isolated and characterized using Acidified Potato Dextrose Agar (APDA) for samples collected in January 2009 only. A total of 7 and 6 species were identified from among the isolates in oiled and unoiled sites. Although there is a little difference in species composition, almost all the isolated species was frequently occurring in both oiled and uncoiled sites. Gliomastix morurom (5.8%) in the unoiled site was only frequently occurring. The results may imply that difference in frequency of occurrence of certain species might be an indicator for sub-lethal effects of oil but needs further investigations to consider environmental factors among other factors.