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Journal Articles - UP - MSI

Permanent URI for this collectionhttps://repository.unesco.gov.ph/handle/123456789/50

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  • The Lingayen Gulf (Philippines) experience: if we have to do it again
    Talaue-McManus, Liana; Eng, Chua Thia (Elsevier BV, 1997-01)
    The coastal management of the Lingayen Gulf represents a pioneering effort in the Philippines to manage a coastal area that is larger than small islands. After 4 years of research and plan preparation, implementation was initiated with the declaration of the Gulf as an environmentally critical area, and the establishment of the Lingayen Gulf Coastal Area Management Commission. An analyses of the organization and performance of the Commission provided major lessons for future initiatives in coastal management. Programs on law enforcement through punitive measures and vigorous public environmental education through the mass media are easy to implement, and have significant potential to create immediate positive impact among local communities. At the same time, a program on capacity building of management partners at all local governance levels, is crucial for long-term impact. Otherwise, programs on resource management and livelihood development, which require substantial technical inputs, cannot be appropriately implemented.
  • Yield estimates, catch, effort and fishery potential of the reef flat in Cape Bolinao, Philippines
    Campos, W. L.; del Norte-Campos, A. G. C.; McManus, J. W. (Hindawi Limited, 1994-10)
    Catch, fishing effort and yield estimates of the Cape Bolinao reef flat fishery in Lingayen Gulf, Philippines are provided, based on data collected from May 1987 to April 1988. The dynamics of the dominant species, the rabbitfish Siganus fuscescens, suggest that such fisheries are capable of maintaining a high production in site of heavy fish in pressure. However, yield comparisons with those of other reef fisheries in the Indo-Pacific region, along with characteristics of the catch and the use of multiple gear types, suggest that current extraction rates should not be increased.
  • Aspects of the growth, recruitment, mortality and reproduction of the scallop Amusium pleuronectes (Linné) in the Lingayen Gulf, Philippines
    Del Norte, A. G. C. (Informa UK Limited, 1988-11)
    Growth, recruitment, mortality and reproduction were investigated in the Asian moon scallop, Amusium pleuronectes (Linne) from the Lingayen Gulf, Philippines. Allometric relationships were defined by comparing different shell dimensions, as well as body weight proportions including total weight with shell, visceral weight, adductor muscle weight and gonad weight. Use of the von Bertalanffy-based ELEFAN I program yielded estimates of growth parameters equivalent to H ∞ = 106Dimshell height and K = 0.92 per year, with approximate longevity for the species of about 2 years. Recruitment, as derived using the ELEFAN II program, occurred throughout the year, but showed a pattern consisting of one major and one minor pulse separated by an 8- and 4-months interval. Fishing mortality (F = 5.3) was higher than natural mortality (M = 1.9). Spawning occurred throughout the year, with one major peak in February and one minor peak between July and September, thereby providing some biological basis to the recruitment pattern indicated. Protandry and size at sexual maturity (54 mm) in the species were confirmed.
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    Shallow structures, interactions, and recurrent vertical motions of active faults in Lingayen Gulf, Philippines
    Flores, Paul Caesar M.; Siringan, Fernando P.; Mateo, Zenon Richard P.; Marfito, Bryan J.; Sarmiento, Keanu Jershon S.; Abigania, Maria Isabel T.; Daag, Arturo S.; Maac-Aguilar, Yolanda (Elsevier, 2023-06-01)
    The surface trace of the East Zambales Fault (EZF) and its associated faults in the Lingayen Gulf have been previously mapped but no other characteristics were reported. This study utilized seismic reflection, multi-beam bathymetry, and side scan sonar to characterize the offshore EZF in terms of magnitudes of vertical displacement. Sequence stratigraphy and radiocarbon dates provided age constraints on the recurrence interval within the Holocene. The EZF extends for ∼ 57 km into the gulf, follows a north-northwest trend, and bounds the karstic terrane (west) and fluvio-deltaic deposits (east). Sinistral motion is indicated by: 1) normal and reverse drag geometries, 2) reversal in the sense of throw with depth, 3) flower structure, and 4) right-stepping and the uplift of a pressure ridge named Pudoc Bathymetric High. The Central Lingayen Gulf Fault (CLGF), to the east of EZF, follows the same trend. The Lingayen Gulf Transverse Fault (LGTF), oriented east–west, forms a flower structure with the CLGF. The EZF, CLGF, and LGTF combined form the Lingayen Gulf Fault System, which divides the gulf into five fault blocks where uplift and subsidence locally occurred. A paleo-delta at −60 m yielded an age of 6.8 kyBP, indicating it was formed during the first Holocene highstand. With natural compaction considered, fault-associated subsidence of 46–53 m may have occurred. The average Holocene vertical displacement is 2.1–2.2 m, which translates to a recurrence interval of 320–270 years for the fault system. The faults can likely generate earthquakes with magnitudes 7.5 (EZF), 6.7 (CLGF), and 6.6 (LGTF).
    This work was supported by grants to F. P. Siringan by the Department of Science and Technology – Philippine Council for Industry, Energy and Emerging Technology Research and Development through the Mapping of Active Offshore Faults for Resilient Coasts Project; and the Department of Environment and Natural Resources – Biodiversity Management Bureau through the Coral Reef Visualization and Assessment - Deep Coral Mapping Project. We are thankful to Deo Carlo Llamas for the meaningful discussions about the current knowledge of the East Zambales Fault. We also thank the anonymous reviewers who provided significant insights for the improvement of this manuscript.