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UPV Theses and Dissertations

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    Mangrove community structure survey in Pedada Bay, Ajuy, Iloilo
    Bravo, Mark G. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2004-04)
    Mangroves are uniquely tropical, globally occurring and one of the most pervasive coastline ecosystems. They are one of the highly productive and one of the most diverse wetlands on earth. The objective of this study is to assess the community structure of mangroves in Pedada Bay, Ajuy, Iloilo, in particular the species composition and diversity in relation to the physical and chemical factors. Pedada Bay is located in the northern part of Panay Island. The transect line plot method was used to survey the community structure of the mangroves. The floristic composition of Pedada Bay was composed of a total of 18 true mangrove species belonging to 11 families. The true mangroves were Family Avicenniaceae represented by Avicennia marina and A. rumphiana, Family Bombacaceae represented by Camptostemon philippinensis, Family Combretaceae represented by Lumnitzera racemosa, Family Euphorbiaceae represented by Exoecaria agallocha, Family Meliaceae composed of Xylocarpus granatum and X. moluccensis, Family Myrsinaceae composed of Aegiceras corniculatum and A. floridum, Family Myrtaceae represented by Osbornia octodonta, Family Palmae represented by Nypa fruticans, Family Rhizophoraceae composed of Bruguiera cylindrica, Ceriops decandra, Rhizophora apiculata, R. mucronata, and R. stylosa, Family Rubiaceae, composed of Scyphiphora hydrophyllacea, and Family Sonneratiaceae, composed of Sonneratia alba. Average basal area for the entire Pedada Bay ranges from 300.564 m2/ha for Sonneratia alba to 0.008 m2/ha for Rhizophora mucronata. Average stems per hectare ranges from 1,988 for Avicennia marina to 5 stems per hectare for Aegiceras corniculatum. Of the three barangays of Pedada Bay, Barangay Pedada had the highest basal area while Barangay Luca had the lowest basal area. Sonneratia alba was the most dominant species in the bay. Avicennia marina was the densest, the most frequently occurring, and the most important species in Pedada Bay. The entire area had a high diversity index of 0.718. A distinct zonation pattern was observed in the area. Seedling density ranges from 1,421 seedlings for Sonneratia alba to 1 seedling for Scyphiphora hydrophyllacea. Sapling density ranges from 166 for Avicennia marina to 1 for Scyphiphora hydrophyllacea.
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    Diversity and structural complexity of mangrove stands in Barangay Mag-aba, Pandan, Antique
    Bolivar, Lucille S. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)
    Mangrove forests provide a variety of ecological functions and economic services. However, full realization of these is also hampered by lack of understanding of the structural complexity that brings about a unique ecosystem. There is a need to understand the current status and dynamics of mangroves under threats of both natural and anthropogenic factors. The mangrove forest at Barangay Mag-aba, Pandan, Antique, that is part of the Northwest Panay Peninsula Natural Park, is one of the few patches of mangroves in Antique offering good opportunity to study diversity and stand structure. This study provides an important baseline data for conservation efforts and for comparison with other mangrove stands in the region. This study aimed to assess qualitatively and quantitatively the mangrove community structure of the Mag-aba mangrove forest. Specifically, the objectives of this study included (1) determination of selected physical and chemical factors affecting mangroves, (2) identification and classification of true mangrove species in the area and (3) analysis of the community structure. The modified line plot method for community structure survey was applied. A total of 19 true mangrove species from eight families were recorded in the area with Family Acanthaceae being the most represented. The stand basal area of 35.48 m2/ha was indicative of a mature community system. Structure analysis showed that Excoecaria agallocha (31.31%) was the most dominant species and had the highest importance value (81.29) followed by Bruguiera cylindrica, Xylocarpus granatum and Sonneratia alba. Trees made up 50% of the community composition with a density of 2044.44 t/ha. Barangay Mag-aba had a mean species diversity index (H’) of 0.95 indicating a low number of species present and a mean species evenness value (J’) of 0.38 indicative of an unequal species distribution. High complexity and diversity were observed in the upper intertidal zone where soil salinity is low. These results provide important insights to the underlying ecological functions of the mangroves in the area as basis of a more dynamic and intensive conservation action.
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    A quantitative and qualitative analyses of phytoplankton in Lamentao, Barotac Nuevo, Iloilo
    Boglosa, Jescel B. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2000-03)
    The study was conducted to identify the different genera of phytoplankton in Lamentao, Barotac Nuevo, to determine the distribution and composition of phytoplankton both near shore and offshore and to determine the physico-chemical characteristics in both sampling sites. The samples were obtained near shore (10m) and offshore (15m) for 10 minutes. Towing was done at 12 noon for 200 m. Sampling was done once a month for three consecutive months starting October to December. Each sample was allowed to stand for at least 24 hours. Then these were decanted to have a concentrated sample. Then 1ml sample was introduced in a sedge wick counting chamber for identification and counting under the microscope. The study gave the following findings: There are 32 genera identified in the surface water of Lamentao. Offshore has a higher abundance than the near shore. There are some genera that significantly differ in 2 sampling area shown by the t-test. Density offshore were generally significantly higher than density nearshore. Relative abundance, Leucosolenia sp. and Rhizosolenia sp. have the higher one. There is a higher diversity in off shore than in near shore. Most of the genera is present in both sites and month as shown by the index of similarity.
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    Community structure of beach forest species in Mag-aba, Pandan, Antique
    Banogon, Tharrah Anne O. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)
    The Philippine beach forest is one of the understudied and less-popular important ecosystem that provides great number of food and economic products in the country. In fact, we lost them much earlier than the mangrove community that there is miniscule information is existing about them. There is a need for understanding the forest status and community structure due to the rising threats of natural and anthropogenic factors. The unexplored forest patch in Barangay Mag-aba, Pandan, Antique can provide additional information on beach forest diversity and abundance in the country, thus the need for this study. This study aimed to record the different species and to provide description of the community of beach forest in Mag-aba, Pandan. Specifically, the objectives of this study are (1) identify, describe and classify the beach forest species present in the area, and (2) describe the community structure in terms of species composition, diameter at breast height and stand height, stand basal area, importance value, evenness and Shannon- Weiner Index of Diversity. The transect plot method adopted from English et al (1994) was used to obtained quantitative data. A total of 80 beach forest species representing 41 families were recorded. The family Fabaceae and the species Cocos nucifera dominated the forest community. The stand basal area of 83.24 m2 ha-1 reflects a mature beach forest community, however the community is made up of mostly low DBH classes (saplings and seedling) also indicating a regenerating forest. Mag-aba is characterized to have a low species diversity (H'=1.17), however the individual species are fairly distributed (J'- 0.83). These results are addition to the existing knowledge of beach forest community that would serve as information for conservation measures.