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

2013 - 20192

Settings

AGROVOC Keyword: search.filters.agrovoc.sea grassesSDG: search.filters.sdg.SDG 13 - Climate action

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Temporal variation in the subtidal macroinfaunal composition of a NaGISA seagrass bed in southern Guimaras, Philippines between 2015 and 2016
    Bacabac, Earl Jeroh I. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)
    Seagrass meadows are amongst the most abundant and diverse ecosystems when it comes to biodiversity but due to stress induced by natural and anthropogenic factors, a worldwide decline threatens the vital ecological functions of these habitats. Studying the infauna provides clues and information about the complexity of seagrass ecosystems and provides information that would facilitate better seagrass area management and associated conservation efforts. The NaGISA sampling protocol was conducted in Calaparan seagrass bed in TINMAR, Guimaras, Philippines between Sept. 2015 and 2016. Overall macrofaunal density was recorded at 21,954.80 ± 36,109.62 ind.m'2 with macrofaunal density higher in 2015 than in 2016 albeit, insignificant except for capitellid polychaetes. Community structure analysis also found similarity in dominance patterns in the subtidal zone with other soft-bottom macrofaunal studies in the Philippines with polychaetes, nematodes, and crustaceans as the respective dominant macrofaunal groups observed. Dominant polychaete families were also found to be cosmopolitan and opportunistic. Granulometric analysis characterized the sediment as pebble to medium sand with mid phi values ranging from -3.69 to 1.10 but poor sorting in all sampling points was observed. Cymodoceaceans dominated the subtidal zone in both years (Halodule pinnifolia in 2015; Cymodocea rotundata in 2016). Correlation analysis showed macrofaunal densities to have a significantly strong negative relationship with sorting index and percent gravel while a strong positive relationship with percent seagrass cover. The poor sediment sorting, coarse sediment character, and seagrass cover were the primary factors influencing the observed decrease in macrofaunal density but the decrease is considered normal for the variability of macrofauna in the area. A clearer picture of macrofaunal interactions would be provided with comparison to intertidal macrofauna of the area in the sampling years and data on additional factors that were not measured in the study.
  • Thumbnail Image
    Item
    Spatial variations of Benthic meiofauna communities from Palompon Bay, Northern Leyte
    Balasa, Melvy June (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2013-04)
    Meiofauna play a significant role in maintaining ecological balance in marine ecosystems especially in the dynamics of the seagrass meadows. The meiofauna links the upper trophic level with detritus-feeding organisms. Only few studies have been conducted in the Philippines, while no studies have been. This study was conducted in Palompon, northern Leyte in November 2011, to determine the spatial distribution of meiobenthic fauna in the area and to compare community structure in terms of species composition, species density, and species diversity among five stations included in the survey. Twenty taxa were identified with nematodes being numerically dominant, followed by harpacticoid copepods. It also showed the highest mean abundance for the entire habitat type. The overall mean density was 194585.1528 ind. m2, with the highest population at station 4. And the lowest population was recorded at station 2. Soft bottom habitat showed the highest recorded mean density among the 5 stations, Harpacticoids mostly dominated sandy substrate while nematodes were widely distributed.