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03. Science and Technology (Natural Sciences) Committee

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In creating a culture of peace and addressing sustainable development challenges, UNESCO aims to cultivate the generation and application of scientific knowledge among its Member States. At UNACOM, we facilitate access to UNESCO’s international programmes in the sciences, such as the Intergovernmental Oceanographic Commission (IOC), Man and the Biosphere (MAB) Programme, and International Geoscience and Geoparks Programme (IGGP), among others.

Through this sector, the Commission aims to contribute to the following SDGs: 11 - Sustainable Cities and Communities, 13 - Climate Action, 14 - Life Below Water, and 15 - Life On Land. With the overarching vision of the 2023-2028 Philippine Development Plan (PDP), UNACOM targets grassroots-inspired cultural heritage and biodiversity protection and conservation, as well as multi-stakeholder partnerships for SDGs promotion.

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Author: search.filters.author.Lopez, M. D. G.End date: 2019

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    Calanoides acutus in Gerlache Strait, Antarctica II. Solving an inverse problem in population dynamics
    Huntley, M. E.; Zhou, M.; Lopez, M. D. G. (Elsevier, 1994-01)
    A population dynamics model of the overwintering Southern Ocean copepod, Calanoides acutus, was constructed based on field observations of abundance in the Gerlache Strait during November 1989. We used an analytical solution to solve an inverse problem to determine rates of stage-specific mortality and development as the population emerged from overwintering diapause. Model predictions of mortality rates for CIV, CV and CVI copepodites were 0.068, 0 and 0.131 day−1, respectively. Best fit solutions of the model predict that late-stage copepodites emerge from diapause by “pulse moulting;” overwintering copepodites appear to emerge from diapause en masse in a relatively brief period prior to the annual spring bloom, rather than moulting at the comparatively slow rates observed in summer. We suggest that the modelling approach we used may have application to many species of copepods whose populations overwriter.
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    Effect of starvation on development and survivorship of naupliar Calanus pacificus (Brodsky)
    Lopez, M. D. G. (Elsevier, 1996-10)
    In the marine planktonic copepod, Calanus pacificus (Brodsky), survivorship and development rate during the remaining naupliar stages were reduced when initial feeding was delayed for ~ 10 h after molting into naupliar stage III (NIII). In otherwise well-fed stages NIII-NVI, development and survivorship were reduced after starvation periods > 6 h and > 14 h, respectively. Molting rate and survivorship were lower in response to transient starvation than in response to constantly low food supplies. Stage NV was the least sensitive to transient starvation, while stages NIII and NVI were the most susceptible. Molting rates were reduced even after abundant food was subsequently provided. Thus, ambient food concentration at the time a population is sampled may not be an adequate index of future cohort success. Estimates of fine-scale to micro-scale particle distributions in situ suggest that NIII, the first feeding stage, is the instar most likely to experience short starvation periods if hatching occurs well below phytoplankton-rich strata.
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    Feeding and diel vertical migration cycles of Metridia gerlachei (Giesbrecht) in coastal waters of the Antarctic Peninsula
    Lopez, M. D. G.; Huntley, M. E. (Springer, 1995-01)
    Diel vertical migration and feeding cycles of adult female Metridia gerlachei in the upper 290 m of a 335-m water column were measured during a total of 65 h in two periods of early summer (Dec 20–21 and Dec 25–26, 1991). Samples collected in eight depth strata by 35 MOCNESS tows (333-μm mesh) were analyzed for abundance and mean individual gut pigment content. Most of the copepod population was concentrated in a 50-m depth interval at all times. Feeding began simultaneously with nocturnal ascent from a depth of 200–250 m at ≈ 18:00 h (local time), when the relative change in ambient light intensity was greatest. Ingestion rate increased exponentially (ki = 0.988 h−1) at double the gut evacuation rate (ke = 0.488 h−1) as the population moved upward at 22.3–26.5 m h−1 through increasing concentrations of particulate chlorophyll-a. Although the bulk of the population did not move to depths shallower than 50 m, and began its downward migration at a rate of 20.8–31.7 mh−1 in complete darkness, individual females continued to make brief excursions into chlorophyll-rich surface waters (4–8 μg l−1) during the first few hours of population descent. Ingestion rate diminished abruptly by one order of magnitude (ki = 0.068 h−1) at dawn (≈ 03∶30 h). Within four more hours, the population had reached its daytime depth and gut pigment content remained constant at a minimum value until the next migration cycle. No feeding appeared to take place at depth during the day. Ingestion by M. gerlachei females removed < 4% of daily primary production, with only ≈ 20% of this amount being removed from surface waters by active vertical transport.