Mr. James L. Falter and Dr. Francis J. Sansons of the Department of Oceanography, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa.
20000914
Unknown
Pore water studies reef flat sediments, Kaneohe Bay, Oahu, HI (NODC Accession 0000271)
None
Digital files
Honolulu, HI
University of Hawaii at Manoa
Geochemical behavior of the upper 70 cm of permeable reef flat sediments on Checker Reef, Oahu, Hawaii was examined using spatial and temporal changes in pore water dissolved oxygen, nitrate, nitrite, ammonium, and nitrous oxide. This patch reef was monitored immediately following significant wave events (storm events) between October 1996 and July 1997 to study the hydraulic control of pore water geochemistry within the oxic-suboxic zone of a permeable sediment.
The purpose of this study was to examine the behavior of the water composition within these permeable sediments and their relationship to sediment redox structure under varying physical condtions.
Resource Description: NODC Accession # 0000271
19961001
Unknown
19970731
ground condition
None planned
Checker Reef, Oahu, Hawaii
-157.792
-157.791
21.442
21.442
NCEI Geoportal FilterCoRIS_Metadata
CoRIS Theme Thesaurus
EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrate
EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrite
EARTH SCIENCE > Oceans > Ocean Chemistry > Dissolved Gases
EARTH SCIENCE > Oceans > Ocean Chemistry > Oxygen
EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs
EARTH SCIENCE > Biosphere > Aquatic Habitat > Reef Habitat
EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Patch Reef
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Benthos Analysis
EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrogen > Dissolved Inorganic
none
silicon
nitrous oxide
dissolved inorganic phosphorous
pore water geochemistry
sediments
ammonium
CoRIS Discovery Thesaurus
Numeric Data Sets > Chemistry
ISO 19115 Topic Category
geoscientificInformation
008
CoRIS Place Thesaurus
OCEAN BASIN > Pacific Ocean > Central Pacific Ocean > Hawaiian Islands > Oahu Island > Checker Reef (21N157W0009)
COUNTRY/TERRITORY > United States of America > Hawaii > Honolulu > Checker Reef (21N157W0009)
CoRIS Region
MHI
CoRIS Theme Thesaurus
EARTH SCIENCE > Biosphere > Aquatic Habitat > Benthic Habitat
EARTH SCIENCE > Biosphere > Aquatic Habitat > Reef Habitat
None
None
Patrick Caldwell
NOAA/NODC/National Coastal Data Development Center
NOAA/NODC Hawaii/Pacific Liaison
mailing and physical address
JIMAR, University of Hawaii at Manoa, 1000 Pope Road
Honolulu
HI
96822
U.S.A.
808-956-4105
808-956-2352
Patrick.Caldwell@noaa.gov
8:00 a.m. to 4:00 p.m. Monday through Friday
call, write, e-mail, FAX, leave voice mail
Mr. James L. Falter and Dr. Francis J. Sansone
Microsoft EXCEL
See originator data files and methodolgy description.
See originator data files and methodolgy description.
Field
CoRIS Theme Thesaurus
EARTH SCIENCE > Biosphere > Zoology > Corals > Reef monitoring and assessment > Benthos analysis
Pore water geochemistry
Sediment cores - coral reef
Water composition
ammonium
dissolved inorganic phosphorous
EARTH SCIENCE > Oceans > Ocean Chemistry > Dissolved Gases
EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrate
EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrite
EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrogen > Dissolved inorganic Nitrogen
EARTH SCIENCE > Oceans > Ocean Chemistry > Oxygen
nitrous oxide
pore water geochemistry
sediment analysis
silicon
Well points were fabricated from 1/8 in. diameter schedule 80 PVC pipe and used to sample pore water at depths of 7,15,25,35,50, and 70 cm in the reef. The well points were driven into the reef framework with the aid of a stainless steel installion tool. A set of wells for sampling each of these depths defined an array. The arrangement of wells within a single array was designed to minimize the degree of lateral separation of any two wells within an array while preventing the pore water volume extracted from one well point from overlapping or interfering with the volume extracted from an adjacent well. The sampling volume was estimated to be a sphere ~6 cm in radius, based upond a total extraction volume of ~250 ml per sampling and an estimated sediment porosity of ~0.3. The porosity of modern aragonitic sands is typically ~0.45; however, a more conservative estimate of porosity is used for Checker Reef sediments due to the presence of the larger pieces of broken coral rubble.
Pore water samples were extracted from the sediment using a battery-powered perstaltic pump. An amount in excess of the dead volume in the tubing that connected the well point to the pump (~270ml) was collected and discarded before taking each 250 ml pore water sample to ensure a pure pore water sample. The mixing of pore water during its passage through the tubing acted to homogenize the samples; however, samples collected from individual well points on and after 1 March 1997 were homogenized in a glass flask free of any head space to ensure uniformity between subsamples intended for different chemical analyses. There did not appear
to be any significant change in the relative distribution of pore water species once this deliberate homogenization step was employed. An additional experiment was performed to determine how much pore water composition would change with the volume of water extracted. Four 60 ml pore water samples were sequentially taken from 7-, 25-, and 50-cm well points at each station using 60 ml syringes attached directly to the well points (without using the pump and tubing). These samples showed that nitrate and ammonium concentrations did not change significantly with the amount of pore water extracted, even for the 7-cm well points, suggesting that there was no enhanced
movement of pore water along the sides of the well points.
Two arrays ~1.5 m apart were installed at varying distances from the forereef (Stations S and C) and sampled over a 9-month period. At no point was there a freshwater flow into the bay large enouch to effect surface salinities over the reef. Samples for the determination of dissolved nitrate, nitrite, and ammonium were filtered through glass fiber filters and analysed using standard colorometric techniques. Dissolved oxygen was measured in the field using an Orion model 820 dissolved oxygen meter equipped with a Clark-type electrode. Pore water nitrous oxide concentrations were measured following the method of Pierotti and Rasmussen (1980) with only minor
modifications.
Sediment hydraulic conductivity was estimated for each of the well points using a falling-head permeameter. These estimates assumed that the sediments were homogeneous and extended infinitely around a given well point. These assumptions were made to simplify the required calculations; however, the sensitivity of the calculations to these assumptions at distances greater than 7 cm away from the well point was very small ( less than 5%).
#INSTRUMENT TYPES:
Wells: 1/8 in. diameter schedule 80 PVC pipe
Water extraction: battery-powered perstaltic pump and 60 ml syringes
Dissolved oxygen was measured in the field using an Orion model
820 dissolved oxygen meter equipped with a Clark-type electrode.
See details under methodogy description in this metadata record and within originator data files.
19970731
NOAA National Oceanographic Data Center
NODC User Services
not applicable
mailing and physical address
1315 East-West Highway, SSMC3, 4th Floor
Silver Spring
MD
20910
U.S.A.
301-713-3277 or 3280
301-713-3302
nodc.services@noaa.gov
8:30 AM through 6:00 PM, Monday through Friday EST
Phone/e-mail/FAX/voice mail message
Downloadable Data
NOAA makes no warranty regarding these data, expressed or implied, nor
does the fact of distribution constitute such a warranty. NOAA and NODC
cannot assume liability for any damages caused by any errors or
omissions in these data, nor as a result of the failure of these data to
function on a particular system.
Microsoft XLS
19970731
Not applicable
Original file received by NODC via FTP in file, appx.xls (Microsoft EXCEL). Redundant ASCII text files were made of each individual sheet within the spreadsheet file at the NODC for archival purposes. Original files are: sheetx.prn, where x varies from 1 to 8. The format is straight-forward with well-defined columns. Rows are clearly marked by date and depth. Dataset size: 91 Kbytes. Number of data units: 2 stations, 4 arrays.
None required; uncompressed files
https://accession.nodc.noaa.gov/0000271
NODC Data Direct functions through standard Internet browsers; FTP capability required; access "Data Direct" through the NODC website at www.nodc.noaa.gov; go to "year 2000" and select NODC Accession # 0000271
Standard Internet browser; FTP capability; PC, Mac, or UNIX system, Microsoft EXCEL or compatible suggested
None
Download through via NODC's "Data Direct" system at the NODC homepage at www.nodc.noaa.gov or contact NODC for custom order. (When requesting data from the NODC, the desired data set may be referred to by the 7-digit number given in the RESOURCE DESCRIPTION field of this metadata record)
24 hours if downloaded via the Internet
Contact the NODC User Services Group via phone/FAX/E-mail: nodc.services@noaa.gov
Microsoft Excel 97 or higher, or compatible software
20011207
Unknown
Present
Unknown
20200329
20030731
Sheri Phillips
NOAA/NODC
Oceanographer
mailing and physical address
1315 East-West Highway, E/OC1, SSMC3, 4th Floor
Silver Spring
MD
20910
U.S.A.
301-713-3280 x127
301-713-3302
sheri.phillips@noaa.gov
9:30 AM - 6 PM Monday-Thursday
E-mail, phone, FAX, mail
FGDC Biological Data Profile of the Content Standard for Digital Geospatial Metadata
FGDC-STD-001.1-1999
Local Time
None
Dataset credit recommended/desirable
Unclassified
Unclassified
None
20020814083644
None
19961001
19970731
https://www.coris.noaa.gov/metadata/records/html/nodc_0000271_pore_studies.html
154