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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14583/13

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AGROVOC Keyword: search.filters.agrovoc.mangrovesDegree: search.filters.degree.Bachelor of Science in Biology

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    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.
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    A community study of mangroves in Brgy. Caliling, Cauayan, Negros Occidental
    Barredo, Sherry Marie P. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2000-03)
    The species distribution of the mangrove community in Brgy. Caliling, Cauayanz Negros Occidental was studied using the transect line plot method with three plots for each of four stations established. Both stations 1 and 4 were located landward, while stations 2 and 3 were located seaward. Community structure Is described in terms of the following parameters; basal area, number of trees per hectare, importance value, relative density, relative frequency, frequency of species and relative dominance. Variations in these parameters are correlated with physico-chemical factors such as the air, water and soil temperature, water depth, salinity and pH. Ten true species were found In the mangals of the coastal environment of Brgy. Caliling, Cauayan, Negros Occidental. They were Avicennia aiba, Avicennia Janata, Avicennia manna, Campostemon phiiHpinensis, Excoecaria agallocha, Osbomia octodonta, Nipa fruticans, Brugeria cylindrica, Rhizophora apiculata and R. mucronata. Standard Basal Area was highest in Station 3 with 7.54 m/ha. In terms of zonation, the landward zone was found to have the highest Stand Basal Area with 11.15 m/ha. Station 2 had the highest density value of 33.92 %, whereas in terms of zonation, both the middle and seaward zone had the density value of 36.20 %. Avicennia marina was found to be the most dominant species and was observed to occupy sites with hypersaline conditions, in silty clay to muddy substratum, which may or may not be inundated by tidal flow most of the time.
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    Community structure of a ten-year-old naturally, regenerating mangrove stand in Baguingin, Tigbauan, Iloilo
    Animas, Ruphil May J. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 1999-04)
    The structure of the mangrove community in Baguingin, Tigbauan was studied using the transect line plot method with seven plots established. Community structure is described in terms of the following parameters: basal area, stems per hectare, relative density, relative frequency, relative dominance, and importance value of the species and the Shannon Index of Diversity. Variations in these parameters are correlated with certain physico-chemical factors-- air and water temperature, soil pH, water salinity, land elevation- and the degree of human influence. Three true mangrove species were found in the area: Excoecaria agallocha, Avicennia marina, and Avicennia alba. A. marina was found to have the highest relative density of 70.8%. relative dominance of 52.35% and importance value of 169.82. A. marina and A. alba have equal relative frequency of 46.67%. Seedlings and saplings of A. marinadominate the area, indicating that the community is a young and regenerating stand. Basal area significantly increased from sea to land ( 53.68 cm2 to 431.66 cm2) and from creek to land ( 8.83 cm2 to 366.54 cm2). Shannon Index of Diversity gave a result of 0. The very low diversity index means that there is uneven distribution of individual trees among the species, and only a few kinds of species were present and are centered around only two genera, Avicennia species and Excoecaria agallocha.