gov.noaa.nodc:0282643 eng utf8 dataset NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NOAA Contact Information Information for contacts at NCEI. information custodian 2026-07-29T13:15:23Z ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) Seagrass density and biomass, and related data from seagrass monitoring station LM-151 in Laguna Madre Texas from 1989-03-24 to 2022-06-23 (NCEI Accession 0282643) 2023-09-13 publication 2023-09-11 creation International DOI Foundation (IDF) 10.25921/w3c1-sx54 NOAA National Centers for Environmental Information gov.noaa.nodc:0282643 NCEI Archive Management System 0282643 NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information publisher UT Austin Marine Science Institute http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information resourceProvider Kenneth Dunton The University of Texas System ken.dunton@utexas.edu https://www.utsystem.edu/ HTTPS The University of Texas System website Institution web page information principalInvestigator Kim Jackson UT Austin Marine Science Institute http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information collaborator Susan Schonberg UT Austin Marine Science Institute http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information collaborator Kyle Capistrant-Fossa UT Austin Marine Science Institute kyle.capistrantfossa@utexas.edu http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information resourceProvider Kyle Capistrant-Fossa UT Austin Marine Science Institute kyle.capistrantfossa@utexas.edu http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information pointOfContact Dunton, Ken The University of Texas https://www.utsystem.edu/ HTTPS The University of Texas System website Institution web page information author Jackson, Kim University of Texas - Austin, Marine Science Institute http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information author Schonberg, Susan University of Texas - Austin, Marine Science Institute http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information author Capistrant-Fossa, Kyle University of Texas - Austin, Marine Science Institute http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information author The University of Texas System https://www.utsystem.edu/ HTTPS The University of Texas System website Institution web page information contributor UT Austin Marine Science Institute http://www.utmsi.utexas.edu HTTP UT Austin Marine Science Institute website Institution web page information contributor tableDigital This dataset contains raw sampling data beginning in 1989 for a long-term environmental and seagrass monitoring station in Laguna Madre (“LM-151”). This project served to understand environmental drivers of long-term changes in seagrass condition within the Upper Laguna Madre, Texas. Environmental parameters measured within the water column include water depth, dissolved oxygen concentration, underwater light level, pH, salinity, Secchi depth (turbidity), water temperature, total suspended solids, and dissolved inorganic nitrogen and ammonium. Seagrass biological parameters measured are above/belowground biomass and shoot density. Typical seagrass species represented within the data include Halodule wrightii (shoal grass) and Syringodium filiforme (manatee grass). Sampling was dependent on funding/resource availability and local weather conditions, therefore temporal gaps in data may exist. Data are provided in CSV format. This dataset is available to the public for a wide variety of uses including scientific research and analysis. Funding Agency: Texas General Land Office Funding Agency: Coastal Bend Bays & Estuaries Program Funding Agency: US DOI; National Park Service completed historicalArchive NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information pointOfContact asNeeded https://www.ncei.noaa.gov/access/metadata/landing-page/bin/gfx?id=gov.noaa.nodc:0282643 Preview graphic PNG 0282643 NCEI ACCESSION NUMBER 2023-07-17 publication AMMONIUM (NH4) BIOMASS DISSOLVED OXYGEN irradiance NITROGEN pH SALINITY SEA GRASSES - DENSITY Secchi depth suspended solids turbidity water depth WATER TEMPERATURE theme NODC DATA TYPES THESAURUS bottle corer multi-parameter water quality sensor PAR Sensor refractometer Secchi disk instrument NODC INSTRUMENT TYPES THESAURUS in situ theme NODC OBSERVATION TYPES THESAURUS The University of Texas System UT Austin Marine Science Institute dataCentre NODC COLLECTING INSTITUTION NAMES THESAURUS UT Austin Marine Science Institute dataCentre NODC SUBMITTING INSTITUTION NAMES THESAURUS Coastal Waters of Texas place NODC SEA AREA NAMES THESAURUS oceanography theme WMO_CategoryCode 2012-09-15 publication EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > PLANTS > ANGIOSPERMS (FLOWERING PLANTS) > MONOCOTS > SEAGRASS EARTH SCIENCE > BIOSPHERE > VEGETATION > BIOMASS EARTH SCIENCE > OCEANS > BATHYMETRY/SEAFLOOR TOPOGRAPHY > WATER DEPTH EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > AMMONIA EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > NITROGEN EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > OXYGEN EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > PH EARTH SCIENCE > OCEANS > OCEAN CHEMISTRY > SUSPENDED SOLIDS EARTH SCIENCE > OCEANS > OCEAN OPTICS > IRRADIANCE EARTH SCIENCE > OCEANS > OCEAN OPTICS > SECCHI DEPTH EARTH SCIENCE > OCEANS > OCEAN OPTICS > TURBIDITY EARTH SCIENCE > OCEANS > OCEAN TEMPERATURE > WATER TEMPERATURE EARTH SCIENCE > OCEANS > SALINITY/DENSITY > SALINITY theme Global Change Master Directory (GCMD) Science Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Dissolved Inorganic Nitrogen SEA GRASSES - BIOMASS bottom irradiance theme Provider Keywords PAR SENSORS > Photosynthetically Active Radiation Sensors SECCHI DISKS > SECCHI DISKS instrument Global Change Master Directory (GCMD) Instrument Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian PVC corer PVC marked in 10 cm segments instrument Provider Instruments OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF AMERICA OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF MEXICO place Global Change Master Directory (GCMD) Location Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian Laguna Madre place Provider Place Names PDR0LR Send2NCEI Submission Package ID accessLevel: public otherRestrictions Cite as: Dunton, Ken; Jackson, Kim; Schonberg, Susan; Capistrant-Fossa, Kyle (2023). Seagrass density and biomass, and related data from seagrass monitoring station LM-151 in Laguna Madre Texas from 1989-03-24 to 2022-06-23 (NCEI Accession 0282643). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/w3c1-sx54. Accessed [date]. Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives. otherRestrictions Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose. eng; USA utf8 environment oceans biota -97.38 -97.36 27.34 27.36 1989-03-24 2022-06-23 NOAA National Centers for Environmental Information +1-301-713-3277 ncei.info@noaa.gov pointOfContact In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media. Contact NCEI for other distribution options and instructions. CSV 0.444 https://doi.org/10.25921/w3c1-sx54 HTTPS Web browser NCEI Dataset Landing Page Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/oas/282643 HTTPS Web browser Descriptive Information Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/download/282643 HTTPS Web browser HTTPS Navigate directly to the URL for data access and direct download. download ftp://ftp-oceans.ncei.noaa.gov/nodc/archive/arc0217/0282643/ FTP Any FTP client FTP These data are available through the File Transfer Protocol (FTP). FTP is no longer supported by most internet browsers. You may copy and paste the FTP link to the data into an FTP client (e.g., FileZilla or WinSCP). download dataset NCEI Accession 0282643 v1.1 was published. 2023-09-13T19:58:39Z NCEI Accession 0282643 v1.1 publication https://www.ncei.noaa.gov/archive/accession/0282643/1.1 HTTPS NCEI Accession 0282643 v1.1 published 2023-09-13T19:58:39Z download dataset Parameter or Variable: water depth (measured); Units: meter; Observation Category: in situ; Sampling Instrument: PVC marked in 10 cm segments; Sampling and Analyzing Method: Station is approached slowly to ensure that the deceleration of the boat does not create a wake and resuspend sediments into the water column. All hydrographic and water column measurements are collected while the vessel is set to drift over the station to minimize interference from sediment plumes generated from physical disturbances of the bottom. Sonde deployment, water transparency and water sample collection must occur within 30 m of the station location. Measurements are made in the following order: (1) PAR, (2) visibility, (3) hydrography, (4) TSS, (5) depth, (6) percent coverage, (7) canopy height, and (8) blade samples for C:N:P ratios. While taking measurements, care is taken not to disturb the sediment or agitate seagrasses. Depth is measured using a PVC pipe marked in 10 cm segments. Care is taken to avoid allowing the PVC pole to sink into soft sediments.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: DISSOLVED OXYGEN (measured); Units: milligram/liter; Observation Category: in situ; Sampling Instrument: YSI - handheld multi-parameter instrument; Sampling and Analyzing Method: Station is approached slowly to ensure that the deceleration of the boat does not create a wake and resuspend sediments into the water column. All hydrographic and water column measurements are collected while the vessel is set to drift over the station to minimize interference from sediment plumes generated from physical disturbances of the bottom. Sonde deployment, water transparency and water sample collection must occur within 5 m of the station location. Measurements are made in the following order: (1) PAR, (2) visibility, (3) hydrography, (4) water samples, (5) depth, (6) biomass cores. While taking measurements, care is taken not to disturb the sediment or agitate seagrasses. The sonde is lowered so that the instrument probes are completely submerged.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: bottom irradiance (calculated); Units: micromole photons/m2/sec; Observation Category: in situ; Sampling Instrument: PAR Sensor; Sampling and Analyzing Method: Near-continuous underwater measurements of canopy-level photosynthetically active radiation (PAR = ca. 400 to 700 nm wavelength) began at LM-151 in 1989 using a LI-193SA spherical (4π) quantum sensor connected to a LI-1000 datalogger (LI-COR Inc., Lincoln, Nebraska, USA). Measurements were taken every minute and integrated over the hour before logging. Average daytime irradiance (ADI) was calculated by taking the monthly mean of daily averaged irradiance values between sunrise and sunset. This metric was chosen for analysis to minimize daily light variability and reflect growing conditions. A thin, optically-clear plastic covering was placed over the sensor and replaced ever 2 - 4 wk to reduce biofouling.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: pH (measured); Units: pH; Observation Category: in situ; Sampling Instrument: YSI - handheld multi-parameter instrument; Sampling and Analyzing Method: Station is approached slowly to ensure that the deceleration of the boat does not create a wake and resuspend sediments into the water column. All hydrographic and water column measurements are collected while the vessel is set to drift over the station to minimize interference from sediment plumes generated from physical disturbances of the bottom. Sonde deployment, water transparency and water sample collection must occur within 5 m of the station location. Measurements are made in the following order: (1) PAR, (2) visibility, (3) hydrography, (4) water samples, (5) depth, (6) biomass cores. While taking measurements, care is taken not to disturb the sediment or agitate seagrasses. The sonde is lowered so that the instrument probes are completely submerged.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: SEA GRASSES - DENSITY (measured); Units: shoots/m2; Observation Category: in situ; Sampling Instrument: PVC corer; Sampling and Analyzing Method: Three replicate cores are used for estimates of above- and below-ground biomass. A 15 cm inner diameter (ID) core is used to sample Thalassia, and a 9 cm ID core is used to sample Halodule, Syrindogium, Ruppia and Halophila. Seagrass species composition is determined by visual in situ analysis of plants observed within a 25 m radius of each site. A PVC (polyvinyl chloride) core is used for the collection of below-ground and above-ground material. Care is taken to keep only the shoots that reside within the diameter of the core. Following placement of the 15 cm core on the seabed, the rubber stopper is removed from the top of the core. For both 9 cm and 15 cm cores, before pressing the core into the sediment, the diver runs their fingers carefully around the bottom of the core. If grass has been pulled under the core, it is removed. The diver then presses and twists the core down into the sediment (10-15 cm depth). The stopper is re-installed in the 15 cm core, and the core rocked back and forth. The diver then works their hand under the core and removes it from the grass bed, making sure to keep their hand under the bottom of the core in order to prevent loss of sample. After emptying the core into a sieve, broken shoots are removed, since these are likely exterior shoots that were cut by the core tube. Samples are then placed in pre-labeled Ziploc bags and immediately placed on ice. In the lab, plants are counted, divided into above and belowground portions, and massed after being dried to a constant weight at 50 C. Values are extrapolated to shoots/m2.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: SEA GRASSES - BIOMASS (measured); Units: grams/m2; Observation Category: in situ; Sampling Instrument: PVC corer; Sampling and Analyzing Method: Three replicate cores are used for estimates of above- and below-ground biomass. A 15 cm inner diameter (ID) core is used to sample Thalassia, and a 9 cm ID core is used to sample Halodule, Syrindogium, Ruppia and Halophila. Seagrass species composition is determined by visual in situ analysis of plants observed within a 25 m radius of each site. A PVC (polyvinyl chloride) core is used for the collection of below-ground and above-ground material. Care is taken to keep only the shoots that reside within the diameter of the core. Following placement of the 15 cm core on the seabed, the rubber stopper is removed from the top of the core. For both 9 cm and 15 cm cores, before pressing the core into the sediment, the diver runs their fingers carefully around the bottom of the core. If grass has been pulled under the core, it is removed. The diver then presses and twists the core down into the sediment (10-15 cm depth). The stopper is re-installed in the 15 cm core, and the core rocked back and forth. The diver then works their hand under the core and removes it from the grass bed, making sure to keep their hand under the bottom of the core in order to prevent loss of sample. After emptying the core into a sieve, broken shoots are removed, since these are likely exterior shoots that were cut by the core tube. Samples are then placed in pre-labeled Ziploc bags and immediately placed on ice. In the lab, plants are counted, divided into above and belowground portions, and massed after being dried to a constant weight at 50 C. Values are extrapolated to g/m2.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: SALINITY (measured); Units: unitless; Observation Category: in situ; Sampling Instrument: YSI - handheld multi-parameter instrument; Sampling and Analyzing Method: Station is approached slowly to ensure that the deceleration of the boat does not create a wake and resuspend sediments into the water column. All hydrographic and water column measurements are collected while the vessel is set to drift over the station to minimize interference from sediment plumes generated from physical disturbances of the bottom. Sonde deployment, water transparency and water sample collection must occur within 5 m of the station location. Measurements are made in the following order: (1) PAR, (2) visibility, (3) hydrography, (4) water samples, (5) depth, (6) biomass cores. While taking measurements, care is taken not to disturb the sediment or agitate seagrasses. The sonde is lowered so that the instrument probes are completely submerged.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: SALINITY (measured); Units: unitless; Observation Category: in situ; Sampling Instrument: refractometer; Sampling and Analyzing Method: Station is approached slowly to ensure that the deceleration of the boat does not create a wake and resuspend sediments into the water column. All hydrographic and water column measurements are collected while the vessel is set to drift over the station to minimize interference from sediment plumes generated from physical disturbances of the bottom. Sonde deployment, water transparency and water sample collection must occur within 5 m of the station location. Measurements are made in the following order: (1) PAR, (2) visibility, (3) hydrography, (4) water samples, (5) depth, (6) biomass cores. While taking measurements, care is taken not to disturb the sediment or agitate seagrasses. A small water sample is placed onto the refractometer and the salinity is recorded.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: Secchi depth (measured); Units: meter; Observation Category: in situ; Sampling Instrument: Secchi disk; Sampling and Analyzing Method: Station is approached slowly to ensure that the deceleration of the boat does not create a wake and resuspend sediments into the water column. All hydrographic and water column measurements are collected while the vessel is set to drift over the station to minimize interference from sediment plumes generated from physical disturbances of the bottom. Sonde deployment, water transparency and water sample collection must occur within 5 m of the station location. Measurements are made in the following order: (1) PAR, (2) visibility, (3) hydrography, (4) water samples, (5) depth, (6) biomass cores. While taking measurements, care is taken not to disturb the sediment or agitate seagrasses. When using a secchi disk for visibility measurements, sunglasses are removed and care is taken to prevent the vessel from shading the disk.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: WATER TEMPERATURE (measured); Units: degrees Celsius; Observation Category: in situ; Sampling Instrument: YSI - handheld multi-parameter instrument; Sampling and Analyzing Method: Station is approached slowly to ensure that the deceleration of the boat does not create a wake and resuspend sediments into the water column. All hydrographic and water column measurements are collected while the vessel is set to drift over the station to minimize interference from sediment plumes generated from physical disturbances of the bottom. Sonde deployment, water transparency and water sample collection must occur within 5 m of the station location. Measurements are made in the following order: (1) PAR, (2) visibility, (3) hydrography, (4) water samples, (5) depth, (6) biomass cores. While taking measurements, care is taken not to disturb the sediment or agitate seagrasses. The sonde is lowered so that the instrument probes are completely submerged.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: suspended solids (measured); Units: milligram/liter; Observation Category: in situ; Sampling Instrument: bottle; Sampling and Analyzing Method: Replicate water samples were obtained at each station for determination of Total Suspended Solid (TSS) concentration. Bottles and lids are rinsed three times with sample water before collecting the sample. Gloves are worn if the collector is wearing sunscreen to prevent contamination of sample. The TSS method is adapted from EPA Method 160.2. Summary of Method: A well-mixed sample is filtered through a glass fiber filter, and the residue retained on the filter is dried to constant weight at 103-105°C. Sample Handling and Preservation Non-representative particulates such as leaves, sticks, fish, and lumps of fecal matter should be excluded from the sample if it is determined that their inclusion is not desired in the final result. Preservation of the sample is not practical; analysis should begin as soon as possible. Refrigeration or icing to 4°C, to minimize microbiological decomposition of solids, is recommended. Interferences: Filtration apparatus, filter material, pre-washing, post-washing, and drying temperature are specified because these variables have been shown to affect the results. Samples high in Filterable Residue (dissolved solids), such as saline waters, brines and some wastes, may be subject to a positive interference. Care must be taken in selecting the filtering apparatus so that washing of the filter and any dissolved solids in the filter minimizes this potential interference. Laboratory Procedures: 1) Dry new filters at 60°C in oven prior to use. 2) Weigh filter immediately before use. After weighing, handle the filter or crucible/filter with forceps or tongs only. 3) Place the glass fiber filter (i.e. Glass fiber filter discs, without organic binder, such as Millipore AP-40, Reeves Angel 934-AH, Gelman type A/E, or equivalent; Our lab uses 47 mm GF/F 0.7 micron retention) on the membrane filter apparatus. NOTE: Because of the physical nature of glass fiber filters, the absolute pore size cannot be controlled or measured. Terms such as “pore size”, “collection efficiencies” and “effective retention” are used to define this property in glass fiber filters. 4) For a 47 mm diameter filter, filter 100 mL of sample. If weight of captured residue is less than 1.0 mg, the sample volume must be increased to provide at least 1.0 mg of residue. If other filter diameters are used, start with a sample volume equal to 7 mL/cm of filter area and collect at least a weight of residue proportional to the 1.0 mg state above. NOTE: If filtering clear pristine water, start with 1 L. If filtering turbid water start with 100 mL. NOTE: If during filtration of this initial volume the filtration rate drops rapidly, or if filtration time exceeds 5 to 10 minutes, the following scheme is recommended: Use an unweighed glass fiber filter affixed in the filter assembly. Add a known volume of sample to the filter funnel and record the time elapsed after selected volumes have passed through the filter. Twenty-five mL increments for timing are suggested. Continue to record the time and volume increments until filtration rate drops rapidly. Add additional sample if the filter funnel volume is inadequate to reach a reduced rate. Plot the observed time versus volume filtered. Select the proper filtration volume as that just short of the time a significant change in filtration rate occurred. 5) Assemble the filtering apparatus and begin suction. 6) Shake the sample vigorously and quantitatively transfer the predetermined sample volume selected to the filter using a graduated cylinder. Pour into funnel. 7) Remove all traces of water by continuing to apply vacuum after sample has passed through. 8) With suction on, wash the graduated cylinder, filter, non-filterable residue and filter funnel wall with three portions of distilled water allowing complete drainage between washing. Remove all traces of water by continuing to apply vacuum after water has passed through. NOTE: Total volume of distilled rinse water used should equal no less than 50 mLs following complete filtration of sample volume. 9) Carefully remove the filter from the filter support. 10) Dry at least one hour at 103-105°C. Overnight drying ensures accurate filter weight. 11) Cool in a desiccator and weigh. 12) Repeat the drying cycle until a constant weight is obtained (weight loss is less than 0.5 mg). Calculations: TSS (mg/L) is calculated as follows: 1000 x (A-B) x (1000/C) = TSS where A = weight of filter (or filter and crucible) + residue (mg), B = weight of filter (or filter and crucible) (mg), and C = amount of sample filtered (mL).; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: Dissolved Inorganic Nitrogen (measured); Units: micromole/liter; Observation Category: in situ; Sampling Instrument: bottle; Sampling and Analyzing Method: Replicate water samples were obtained at each station for determination of Dissolved Inorganic Nitrogen (DIN) concentration. Bottles and lids are rinsed three times with sample water before collecting the sample. Gloves are worn if the collector is wearing sunscreen to prevent contamination of sample. Samples were processed following Parsons, Maita, and Lalli (1984) Determination of Ammonia (The Alternative Method).; Data Quality Method: Replicate water samples were obtained at each station for determination of Dissolved Inorganic Nitrogen (DIN) concentration. Bottles and lids are rinsed three times with sample water before collecting the sample. Gloves are worn if the collector is wearing sunscreen to prevent contamination of sample. Samples were processed following Parsons, Maita, and Lalli (1984) Determination of Ammonia (The Alternative Method). Parameter or Variable: AMMONIUM (NH4) (measured); Units: micromole/liter; Observation Category: in situ; Sampling Instrument: bottle; Sampling and Analyzing Method: Replicate water samples were obtained at each station for determination of Ammonium (NH4+) concentration. Bottles and lids are rinsed three times with sample water before collecting the sample. Gloves are worn if the collector is wearing sunscreen to prevent contamination of sample. Samples were processed following Parsons, Maita, and Lalli (1984) Determination of Nitrate.; Data Quality Method: Data are checked against reasonable value ranges. Parameter or Variable: DISSOLVED OXYGEN (measured); Units: percent; Observation Category: in situ; Sampling Instrument: YSI - handheld multi-parameter instrument; Sampling and Analyzing Method: Station is approached slowly to ensure that the deceleration of the boat does not create a wake and resuspend sediments into the water column. All hydrographic and water column measurements are collected while the vessel is set to drift over the station to minimize interference from sediment plumes generated from physical disturbances of the bottom. Sonde deployment, water transparency and water sample collection must occur within 5 m of the station location. Measurements are made in the following order: (1) PAR, (2) visibility, (3) hydrography, (4) water samples, (5) depth, (6) biomass cores. While taking measurements, care is taken not to disturb the sediment or agitate seagrasses. The sonde is lowered so that the instrument probes are completely submerged.; Data Quality Method: Data are checked against reasonable value ranges. asNeeded Metadata are developed, maintained and distributed by NCEI. Updates are performed as needed to maintain currentness. NOAA National Centers for Environmental Information custodian bottle bottle any type of water bottle sampling device Generic name for water collection device; usually used to determine temperature, salinity and provide water aliquots for measurement of a wide range of parameters; often referred to by a specific type of water sampling bottle, such as a Nansen or Niskin bottle. corer corer submersible, hydraulic rotary coring drill multi-parameter water quality sensor multi-parameter water quality sensor used to measure temperature, salinity, dissolved oxygen, and other parameters Instrument used to measure temperature, salinity, dissolved oxygen, and other parameters, often used to measure water quality parameters. Can be a hand-held instrument or a sonde for unattended monitoring. Often used in coastal water monitoring stations. YSI is the preeminent brand (as of 2024). PAR Sensor PAR Sensor Photosynthetically Active Radiation Sensor The PAR sensor measures global solar radiation from 400 to 700 nm, which approximates the spectral band active in photosynthesis. The response of the instrument falls sharply to zero on either side of this band, and between 400 and 670 nm it increases monotonically from about 50% to 100%. There is no protective glass dome over the receiving surface. Irradiance from the sun passes through a small white visible bandpass filter/diffuser in the shape of a horizontal disk at the top of the instrument. Within the instrument radiation is directed through a series of colored glass filters and onto a silicon photodiode detector. The factory-supplied calibration converts the signal from the detector to a flux of photons in micro-mole (of photons) s-1 m-2. (One micro-mole equals 6.022 E17 photons.) For the solar spectrum, these units may be converted to watts per square meter by dividing by 4.6. (http://www.srrb.noaa.gov/instrument/par.htm) refractometer refractometer refractometer Secchi disk Secchi disk The Secchi disk (or Secchi disc), as created in 1865 by Angelo Secchi, is a plain white, circular disk 30 cm (12 in) in diameter used to measure water transparency or turbidity in bodies of water. The disc is mounted on a pole or line, and lowered slowly down in the water. The depth at which the disk is no longer visible is taken as a measure of the transparency of the water. This measure is known as the Secchi depth and is related to water turbidity. [Wikipedia, 2021-09-02]