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

2001 - 200932010 - 20192

Settings

AGROVOC Keyword: search.filters.agrovoc.mangrovesKeyword: search.filters.keyword.Community structure

Search Results

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    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.
  • Thumbnail Image
    Item
    The community structure of mangroves in Barangay Poblacion and Barangay Pinamuk-an, New Washington, Aklan
    Blanco, Florence T. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visaya, 2004-04)
    Mangrove ecosystems presently cover an area of about 20 million hectares worldwide. Mangroves grow in environmental settings ranging from highly humid to extremely arid conditions, and in soils which range from pure clays to peat, sand or coral rubble. This study was conducted to assess the community structure of mangroves in Barangay Poblacion and Barangay Pinamuk-an, New Washington, Aklan, using the transect line method of English et al (1995). Specifically, it aimed to determine selected physical and chemical factors such as salinity, pH, temperature for water and soil as well as characterization of substrates; to identify and classify true mangrove species present in the area; to 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 had been conducted to document the community structure of mangroves in New Washington, Aklan. This study was done to provide these vital information needed for its proper management. Five stations were selected in Barangay Poblacion and Barangay Pinamuk-an, New Washington, Aklan. Twenty-two (22) species of mangroves were identified belonging to nine (9) families: Avicenniaceae -Avicennia alab, A marina, a officinalis, A rumphiana; Bombaceae - Camptostemon philippinensis; Combretaceae - Lumnitzera littorea, L racemosa; Euphorbiaceae - Exoecaria agallocha; Meliaceae - Xylocarpus granatum, X moluccensis; Myrsinaceae - Aegiceras corniculatum; Myrtaceae - Osbornia octodonta; Palmae - Nypa fruticans; Rhizophoraceae - Bruguiera cylindrica, B parviflora, Ceriops decandra, Rhizophora apiculata, R mucronata; Rubiaceae-Scyphiphora hydrophyllacea; Sonneratiaceae -Sonneratia alba, S caseolaris; Sterculiaceae-Herittiera littoralis. The study area had a water salinity of 6 ppt to 25 ppt ; water temperature of 27 °C to 30 °C ; soil temperature 27°C to 29°C ; water pH 2.29 to 7.80; soil pH 6.30 and 7.59. Basal area ranged from 0.008 m2/ha for Bruguiera parviflora to 114 nr/ha for Sonneratia alba The species with the highest average stems per hectare recorded was Avicennia rumphiana with 3320. The species with the highest average density recorded was Avicennia rumphiana with a value of 54.984. The station with the highest density was Station 3 and 4 while Station 1 and 5 had the lowest. Two species had the highest Relative Frequency. Xylocarpus granatum and Sonneratia alba were in all stations with 100% occurrence. From the 22 true mangrove species recorded, Avicennia rumphiana had the highest relative dominance of 462.30; the least was Bruguiera parviflora (0.06). The most important species was Avicennia rumphiana (118.51) while the least was Sonneratia caseolaris (1.23). The area is considered to be highly diverse at 0.7835. While on a per plot basis, Station 5 had the highest at 0.9439 while least at Station 1 with 0.5709 Index of Diversity.
  • Thumbnail Image
    Item
    Community structure of riverine mangrove stand in Brgy. Talokgangan, Municipality of Banate, Iloilo Province
    Belaño, Keith Dominador L. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2001-04)
    The community structure of riverine mangrove stand in Brgy. Talokgangan, Municipality of Banate, Iloilo was studied. Ten “true” mangrove species representing seven families were encountered in the “mangals” of Balandra creek community in Brgy. Talokgangan. They were Avicennia marina, Avicennia lanata and Avicennia alba representing Family Avicenniaceae; Rhizophora apiculata and Rhizophora mucronata under Family Rhizophoraceae; Sonneratia alba of the Family Sonneratiaceae; Excoecaria agallocha under Family Euphorbiaceae; Camptostemon philippinense of the Family Bombacaceae; one from the Family Meliaceae namely Xylocarpus granatum, and Family Palmae represented by Nypa fruticans. Stand Basal Area was computed highest in Station 1 with 10.22 m2/ha. Station 1 was also the densest among the four stations with a density value of 2533 trees/ha. In terms of data evaluated per zone, the landward zone has a Stand Basal Area of 10.87 m2/ha which is slightly higher than the middle and riverward zones. The middle zone, however, was found to be the densest with 1850 trees/ha. The most dominant station was Station 1 with the highest Index of Dominance of 0.3319, however, was found to be the least diverse station. The highest Index of Diversity was computed in Stations 2 and 3, with diversity indices of 0.8976 and 0.8989 respectively. Avicennia marina was found common in all stations and the most dominant, making it the most important mangrove species. They were found to occupy the whole site, growing abundantly in wide range of conditions from areas frequently inundated by tidal flow in Station 1 to the firmer muddy substratum in the back mangrove areas. Rhizophora apiculata and Rhizophora mucronata was observed to occupy waterlogged soil conditions. Excoecaria agaliocha tend to flourish in firmer muddy substratum in open sites, whereas, Xylocarpus granatum was observed to occupy zones where salinity is lowest in areas rarely affected by tidal flow. Sonneratia alba and Camptostemon philippinense tend to grow in zones directly inundated by tidal flow.
  • 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.
  • Thumbnail Image
    Item
    Community structure, biomass production and carbon stock assessment of mangroves in Barangay Ambolong, Batan, Aklan
    Agregado, Leizel B. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2013-04)
    Mangroves are evergreen shrubs and trees of several unrelated families that thrive within intertidal zones of sheltered flats, coves, bays, and estuarine regions extending inland along streams and river where water is primarily brackish. Continued threats to their existence call for their protection and conservation. This study was conducted to assess the community structure of mangroves in Brgy. Ambolong, Batan, Aklan by 1). measuring physico-chemical parameters (salinity, temperature, pH) 2). describing the community structure in terms of and in terms of a) basal area, b) stems per hectare, c) relative density, d) relative frequency, e) relative dominance, f) importance value, g) Index of Diversity, h) seedling and sapling density, and i) zonation pattern; 3). to assess the bidmass production and carbon stock. This study was done to provide preliminary information regarding the current status of mangroves in the area. Three (3) transect lines, each containing three (3) plots, were established in the area. Twenty (20) mangrove species belonging to eleven (11) families were identified: Acanthaceae - Acanthus ebreatus, Acanthus volubilis; Arecaceae - Nypa fruticans; Avicenniaceae - Avicennia alba, Avicennia marina, Avicennia officinalis, Avicennia rumphiana; Bombaceae — Camptostemon philippinensis; Euphorbiaceae - Excoecaria agallocha; Meliaceae — Xylocarpus grioanatum, Xylocarpus moluccensis; Myrsinaceae — Aegiceras corniculatum; Myrtaceae - Osbornia octodonta; Rhizophoraceae - Bruguiera cylindrica, Ceriops decandra, Rhizophora apiculata, Rhizophora mucronata, Rhizophora stylosa; Rubiaceae - Scyphiphora hydrophyllacea; Sonneratiaceae - Sonneratia alba. Water salinity in the study area ranged from 27-30 ppt; soil temperature ranged from 28°C to 30°C. Avicennia marina had the highest values for basal area (4.22 m2/ha), stems per hectare (15,700 stems per hectare), relative density (63.56), relative frequency (63.56%), relative dominance (48.10%), and was the most important species with the importance value of 175. Rhizophora stylosa had the lowest values for basal area (0.002 m2/ha), stems per hectare (100 stems/ha), relative density (0.40 trees/ha), relative frequency (0.4%), relative dominance (0.23%), and was the least important species, having the importance value of 0.832. Rhizophora apiculata and Avicennia officinalis, together with Rhizophora stylosa, had the lowest value for stems per hectare (100 stems/ha), relative density (0.40 trees/ha), and relative frequency (0.4%). Seedling density was highest for Avicennia alba(187 seedlings/ha) and lowest for Bruguiera cylindrica (1 seedling/ha). Sapling density was highest for Avicennia marina (54 saplings/ha) and lowest for Excoecaria agallocha (1 sapling/ha). The Index of Diversity was H=0.598. The highest recorded litter was 336.6 g in December 19, 2012-January 2, 2013 while the lowest was recorded at 18.2 grams in December 5-December 29, 2012. Highest biomass production was that of Avicennia marina (962.94 tons/ha), while the lowest was Avicennia officinalis (0.009 tons/ha). Avicennia marina had the highest carbon stock value of 433.32 tons/ha; the lowest was that of Avicennia officinalis (0.004 tons/ha).