Undergraduate Special Problem
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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 Short-term impacts of oil spills on fungal population in a mangrove area in Batad, IloiloAlpas, Donna Bella C. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2014-04)Oil spills cause extensive damage on the marine environment, ranging from obliteration of its flora and fauna to biomagnifications of toxic components of petroleum. The location of mangroves at the sea-land interface makes the ecosystem susceptible to disturbances such as oil spills. There is a considerable information on the impacts of oil spills on mangrove while impacts on microbial populations, especially fungi, are limited. This study therefore assessed the effect of oil on the diversity and distribution of fungi of oil-contaminated sites in Batad, Iloilo due to Power Barge oil spill last November 8, 2013. The mangrove surface sediments were collected on January 11, 2014 at oil-contaminated sites in Batad, Iloilo and uncontaminated site in Ajuy, Iloilo. Sample were processed based on Pepper and Gerba (2004). Colony forming units per gram of soil (CFU/g) was used to express yeasts and filamentous fungi. On PDA medium, more fungal isolates were isolated at oil-contaminated site compared with uncontaminated site at 14 and 12 species respectively, there was also a higher Shannon Index of Diversity at 2.4858 and 2.4582, respectively. Among the filamentous fungi, three genera were represented by Aspergillus. Penicillium, and Cladosporium. However, Aspergillus was more diverse with 10 species. Six species were found only at the oil-contaminated sites - Aspergillus sp 2. Aspergillus sp 1, Cladosporium cladosporioides, Penicillium sp 2, Penicillium sp 3 and Yeast sp 2 while four species are found in the unoiled site - Penicillium cf. lapidosum, Aspergillus sp 3, Aspergillus sp 4 Penicillium sp 1. Furthermore, there is a low index of similarity as shown by Jaccards coefficient of similarity (J=0.44) and Sorensen coefficient of similarity ( C=0.61). Fungal load was higher at oil-contaminated soils compared with uncontaminated soils at 1.3 x 10 - CFU/g and 6.0 x IO3 CFU/g, respectively. Bushnell Haas Agar yielded more fungi isolates isolated from oil-contaminated sites compared with uncontaminated site of 4 and 3 species respectively. Furthermore, a higher Shannon Index Diversity (H) was observed at oil-contaminated sites (1.3298) than those at uncontaminated site (0.6364) suggesting that there are more species of fungi capable to degrade the hydrocarbons and utilize it as a source of energy. The overall frequency of distribution of the major fungal genera in both oil-contaminated and uncontaminated sites showed that only Dueteromycota was isolated and dominated in both sites and in both media, the PDA and Bushnell Haas Agar. The major genera isolated in PDA medium included Aspergillus, Penicillium, Cladosporium, and yeast. In Bushnell Haas Agar, Aspergillus and yeast were the major genera isolated and are seen in both sites. The frequency of occurrence of various species in uncontaminated and oil-contaminated sites were not significantly different. The Deuteromycota were the dominant group that were isolated on all sites using two media. The overall result indicate the stimulating effect of oil are observed in the higher fungal load in oil- contaminated site.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.
