Now showing items 1-3 of 3

    • Article

      Indicators of diminished organic matter degradation potential of polychaete burrows in Philippine mariculture areas 

      SMS Santander, ML San Diego-McGlone & W Reichardt - The Philippine Agricultural Scientist, 2008 - University of the Philippines Los Baños
      Sediments from underneath fish cages and in mesocosm tanks were examined to establish indicators of diminished organic matter degradation potential of polychaete burrows from increased mariculture activities in Bolinao-Anda, Pangasinan, Philippines. Results showed that simple sediment characteristics may be used as sediment quality indicators to describe the contribution of burrows to biodegradable processes in sediments with extremely high deposition of organic particles. The indicators of diminished organic matter degradation potential of polychaete burrows are low redox potential (-113 to -150 mV for F. Spionidae and F. Eunicidae) at the 1 cm surface layer, absence or decreased size of burrow openings, presence of H sub(2)S, disappearance of apparent Redox Potential Discontinuity Layer (aRPD), formation of black sediment, and presence of Beggiatoa (sulfide oxidizing bacteria) and gas bubbles.
    • Parameters in site selection and monitoring 

      SMS Santander - In Training Handbook on Rural Aquaculture, 2009 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Before starting an aquaculture venture, it is necessary to first select an appropriate project site. Doing this ensures that money invested in the project is not later wasted because the site does not meet the requirements of the culture organism. It also makes sure that the environment is not compromised and will be able to sustain the aquaculture activities.

      Two major parameters are considered during site selection. These are the 1) physico-chemical; and 2) environmental parameters. Physico-chemical parameters affect the health of the culture organisms while the environmental parameters will give insights on the sustainability of the aquaculture venture. However, the task does not end with site selection. Monitoring of the aquatic environments is also essential to note any changes in the environment that may affect the aquaculture project and the environment itself.
    • Article

      Status of sea cucumber fishery and populations across sites with different levels of management in Palawan, Philippines 

      JBS Jontila, HM Monteclaro, GF Quinitio, SM Santander-de Leon & JP Altamirano - Ocean and Coastal Management, 2018 - Elsevier
      This study was conducted to investigate the sea cucumber fishery and compare populations between exploited and unexploited sites. Three islands were selected, the Arrecife Island as the unexploited site and the Johnson and Green Islands representing the exploited sites. In each site, sea cucumber species richness, diversity and densities were assessed by laying as much as 15 transects (50 m × 5 m) per habitat in each island. Differences in species richness, diversity and relative densities across sites and habitats were tested using a Two-way Analysis of Variance (ANOVA) and Tukey test for post hoc comparisons. An interview with gatherers, key informants and focus group discussions were also conducted to gather information on the sea cucumber fishery and its management. Results showed that the unexploited site had a higher species richness (14 vs. 7 and 7). Relative density of species was also higher in the unexploited site at 1245 ind ha-1 while it was only 78 and 39 ind ha-1 in exploited sites (p < 0.05). Interviews and a focus group discussion revealed that national regulations on permit system and size limits were not enforced at the local level and that gatherers had low levels of awareness regarding regulations on sea cucumber harvest. Current management measures appear to be ineffective and insufficient, leaving the sea cucumbers in areas open to exploitation at risk of depletion. Given that sea cucumbers provide substantial income to local communities, the depletion of this resource could compromise the livelihood of people in island communities that rely heavily on marine resources for living. Thus, this study highlights the need to review national policies on sea cucumber fishery and place the management at the local level.