UPV Digital RepositoryUPV-DRUniversity of the Philippines Visayas
 

UPV Theses and Dissertations

Permanent URI for this communityhttps://hdl.handle.net/20.500.14583/10

Browse

Filters

2007 - 20092

Settings

Committee Chair: search.filters.chair.Katalbas, Ma. Severa FeKeyword: search.filters.keyword.Mangroves

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Fungal pathogen associated with Rhizophora stylosa: A comparative study between oiled and unoiled sites within Taklong Island National Marine Reserve (TINMAR), Nueva Valencia, Guimaras
    Balanga-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.
  • Thumbnail Image
    Item
    Community structure of mangroves in selected barangays in Sebaste, Antique
    Alorro, Mary Juandin Grace F. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2007-03)
    Mangroves are higher plants that are primarily found predominantly in the intertidal areas such as estuaries and lagoons of the tropical and subtropical shorelines. This study was conducted to assess the community structure of mangroves in Barangay Callan, Barangay Idio, Barangay Poblacion, Barangay Abiera, and Barangay Bacalan, Sebaste, Antique, using the transect line method. Specifically, it aimed to determine selected physical and chemical factors such as salinity, pH, temperature for water and soil as well as characterization of the substrate; identify and classify true mangrove species present in the area; and describe the community structure in terms of stand basal area, stems per hectare, relative density, relative frequency, relative dominance, importance value, Shannon index of diversity, zonation patterns, seedling and sapling density. No study has been done to document the community structure of mangroves in Sebaste, Antique thus, this study was done to provide vital information needed for its proper management. Three stations were selected in Sebaste, Antique. Four (4) species of true mangroves were identified, belonging to three (3) families: Palmae - Nypa fruticans; Rhizophoraceae - Rhizophora apiculata, Bruguiera gymnorrhiza; and Euphorbiaceae - Excoecaria agallocha. The study area had a water salinity range of 0.6 ppt to 15.3 ppt; water temperature range of 28.3°C to 35.4°C; water pH range of 7.1 to 7.7; soil temperature range of 28.3°C to 34.7°C; and soil pH range of 6.5 to 7.2. Basal area ranges from 3.16 m2/ha (Rhizophora apiculata) to 5.88 m2/ha (Excoecaria agallochd) to 8.19 m2/ha (Bruguiera gymnorrhiza) . The species with the highest average of stems per hectare were Excoecaria agallocha and Bruguiera gymnorrhiza with 300 as well as the highest average density value of 100 for Excoecaria agallocha. Nypa fruticans had the highest relative frequency and relative dominance. Among the four species, the most important species was Nypa fruticans. The Shannon Index of Dominance was 0.403 which was quite low in terms of diversity as influenced by the dominance of Nypa fruticans.