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    • Benthic Surveys in Vatia, American Samoa since 2015: benthic images collected during belt transect surveys in 2015 and 2020

    Metadata Updated: October 19, 2024

    Jurisdictional managers have expressed concerns that nutrients from the village of Vatia, Tutuila, American Samoa, are having an adverse effect on the adjacent coral reef ecosystem. Excess nutrient loads promote increases in algal growth that can have deleterious effects on corals, such as benthic algae outcompeting and overgrowing corals. Nitrogen and phosphorus can also directly impact corals by lowering fertilization success, and reducing both photosynthesis and calcification rates. Land-based contributions of nutrients come from a variety of sources; in Vatia the most likely sources are poor wastewater management from piggeries and septic systems.

    NOAA scientists conducted benthic surveys to establish a baseline against which to compare changes in the algal and coral assemblages in response to land-based sources of pollution, including nutrient fluxes.

    Photoquadrat benthic images were collected in 2015 and 2020 only, via belt transect surveys of coral demography according to protocols established by NOAA National Coral Reef Monitoring Program (NCRMP) in 2015.

    In 2015, the survey implemented a two-stage stratified random sampling (StRS) design to assess the Vatia benthic coral reef community, and a one-stage StRS design in 2020. The survey domain encompassed the majority of the mapped area of reef and hard bottom habitats in the 0–30 m depth range. The stratification scheme included cardinal position (i.e., north and south) and depth (i.e., shallow: >0–6 m and mid-depth: >6–18 m). Sampling effort allocation was determined based on strata area and sites randomly located within strata. The StRS design effectively reduces estimate variance through stratification using environmental covariates and by sampling more sites rather than more transects per site. Therefore, site-to-site comparisons should proceed with caution.

    Access & Use Information

    License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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    Dates

    Metadata Date October 3, 2024
    Metadata Created Date October 19, 2024
    Metadata Updated Date October 19, 2024
    Reference Date(s) 2022 (publication)
    Frequency Of Update notPlanned

    Metadata Source

    Harvested from NMFS PIFSC

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Date October 3, 2024
    Metadata Created Date October 19, 2024
    Metadata Updated Date October 19, 2024
    Reference Date(s) 2022 (publication)
    Responsible Party (Point of Contact, Custodian)
    Contact Email
    Guid gov.noaa.nmfs.inport:31196
    Access Constraints Cite As: Pacific Islands Fisheries Science Center, [Date of Access]: Benthic Surveys in Vatia, American Samoa since 2015: benthic images collected during belt transect surveys in 2015 and 2020 [Data Date Range], https://www.fisheries.noaa.gov/inport/item/31196., Access Constraints: None, Use Constraints: Please cite NOAA Ecosystem Sciences Division (ESD) when using the data. Example Cite as: Vargas-Angel, Bernardo; Ecosystem Sciences Division; Pacific Islands Fisheries Science Center (2022). Benthic Surveys in Vatia, American Samoa since 2015: benthic images collected during belt transect surveys in 2015 and 2020. [access date], Distribution Liability: While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by errors or omissions in the data, nor as a result of the failure of the data to function on a particular system. NOAA makes no warranty, expressed or implied, nor does the fact of distribution constitute such a warranty.
    Bbox East Long -170.66666666667
    Bbox North Lat -14.24305555556
    Bbox South Lat -14.25138888889
    Bbox West Long -170.67555555556
    Coupled Resource
    Frequency Of Update notPlanned
    Harvest Object Id 48d8cf86-da92-471a-95c6-b58820c37eec
    Harvest Source Id c0beac72-5f43-4455-8c33-1b345fbc2dfe
    Harvest Source Title NMFS PIFSC
    Licence NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose.
    Lineage Benthic photographs were collected during belt transect surveys of corals by the NOAA Ecosystem Sciences Division (ESD) following the same protocol to that established by the NOAA National Coral Reef Monitoring Plan (NCRMP).
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-170.67555555556, -14.25138888889], [-170.66666666667, -14.25138888889], [-170.66666666667, -14.24305555556], [-170.67555555556, -14.24305555556], [-170.67555555556, -14.25138888889]]]}
    Progress onGoing
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 2015-11-02
    Temporal Extent End 2015-11-12

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