Processing Steps |
- Parameter or Variable: DEPTH - OBSERVATION (measured); Units: meter; Observation Category: in situ; Sampling Instrument: na; Sampling and Analyzing Method: na; Data Quality Method: expert review.
- Parameter or Variable: SECCHI DEPTH (measured); Units: meter; Observation Category: in situ; Sampling Instrument: secchi disk; Sampling and Analyzing Method: Secchi-disk transparency was measured by lowering a white disk that was 25 cm in diameter.; Data Quality Method: expert review.
- Parameter or Variable: WATER TEMPERATURE (measured); Units: degrees Celsius; Observation Category: in situ; Sampling Instrument: thermometer; Sampling and Analyzing Method: Water temperature was obtained by placing a thermometer in a portion of water collected in the Niskin bottle immediately after it was brought to the surface.; Data Quality Method: expert review.
- Parameter or Variable: pH (measured); Units: pH; Observation Category: in situ; Sampling Instrument: pH meter; Sampling and Analyzing Method: pH was measured for collected water upon return to dock. Meter was calibrated daily.; Data Quality Method: expert review.
- Parameter or Variable: CONDUCTIVITY (measured); Units: microsiemens per centimeter; Observation Category: in situ; Sampling Instrument: Sea-Bird 19; Sampling and Analyzing Method: A Sea-Bird CTD with a transmissometer (25-cm beam path) was slowly lowered from the surface to 1 m above the bottom. All data points were logged twice each second.; Data Quality Method: expert review.
- Parameter or Variable: BEAM ATTENUATION (measured); Units: m^-1; Observation Category: in situ; Sampling Instrument: LI-COR 193SB spherical (4 p) light sensor and LI-COR 1000 data logger; Sampling and Analyzing Method: Photosynthetically active irradiation (PAR) was measured at a number of depths in the water column with a LI-COR 193SB spherical (4 p) light sensor and LI-COR 1000 data logger, from which the beam attenuation was calculated.; Data Quality Method: expert review.
- Parameter or Variable: DISSOLVED OXYGEN (measured); Units: milligrams per liter; Observation Category: in situ; Sampling Instrument: Sea-Bird 19; Sampling and Analyzing Method: A Sea-Bird CTD was slowly lowered from the surface to 1 m above the bottom. All data points were logged twice each second.; Data Quality Method: expert review.
- Parameter or Variable: CHLOROPHYLL-A - EXTRACTED (measured); Units: micrograms per liter; Observation Category: laboratory analysis; Sampling Instrument: Turner 10AU; Sampling and Analyzing Method: Chlorophyll (Chl) was measured in triplicate using the method of Strickland and Parsons (1972). Fifty or 100 mL of water was filtered through a 47-mm GF/F Whatman Glass Fiber filter. The filters were placed individually into amber vials containing 5 mL of cold acetone (90 %) and then stored in the freezer. W~thin 30 days, the filters were ground in cold acetone and then steeped for 24 h in the freezer. Samples were centrifuged, the extract poured into a 1-cm curvette, and readings taken with a Turner Design Fluorometer. After an initial reading, 2 drops of 1N HCL were added to the curvette and another reading taken.; Data Quality Method: expert review.
- Parameter or Variable: TOTAL PHOSPHORUS (measured); Units: micrograms per liter; Observation Category: laboratory analysis; Sampling Instrument: Technicon Auto Analyzer II; Sampling and Analyzing Method: Nutrient concentrations were determined using standard automated colorimetric techniques (APHA, 1990) on a Technicon Auto Analyzer II, as detailed in Davis and Simmons (1979). Total phosphorus was determined after digesting 50 mL of unfiltered sample with potassium persulfate in an autoclave using the molybdate/ascorbic acid method.; Data Quality Method: expert review.
- Parameter or Variable: Total Dissolved Phosphorus (measured); Units: micrograms per liter; Observation Category: laboratory analysis; Sampling Instrument: Technicon Auto Analyzer II; Sampling and Analyzing Method: Nutrient concentrations were determined using standard automated colorimetric techniques (APHA, 1990) on a Technicon Auto Analyzer II, as detailed in Davis and Simmons (1979). Total dissolved phosphorus was filtered through a pre-rinsed 0.2-µm HA Millipore filter or a 0.2-µm Nucleopore filter, digested with potassium persulfate in an autoclave and analyzed using the molybdate/ ascorbic acid method.; Data Quality Method: expert review.
- Parameter or Variable: Soluble Reactive Phosphorus (measured); Units: micrograms per liter; Observation Category: laboratory analysis; Sampling Instrument: Technicon Auto Analyzer II; Sampling and Analyzing Method: Nutrient concentrations were determined using standard automated colorimetric techniques (APHA, 1990) on a Technicon Auto Analyzer II, as detailed in Davis and Simmons (1979). Soluble reactive phosphorus was filtered through a pre-rinsed 0.2-µm HA Millipore filter or a 0.2-µm Nucleopore filter and analyzed using the molybdate/ ascorbic acid method. The detection limit for this method is 0.1 µg P/L.; Data Quality Method: expert review.
- Parameter or Variable: AMMONIA (NH3) (measured); Units: mi; Observation Category: laboratory analysis; Sampling Instrument: Technicon Auto Analyzer II; Sampling and Analyzing Method: Nutrient concentrations were determined using standard automated colorimetric techniques (APHA, 1990) on a Technicon Auto Analyzer II, as detailed in Davis and Simmons (1979). Ammonia was filtered through a pre-rinsed 0.2-µm HA Millipore filter or a 0.2-µm Nucleopore filter and analyzed using the Bertholet reaction.; Data Quality Method: expert review.
- Parameter or Variable: nitrate + nitrite content (concentration) (measured); Units: milligrams per liter; Observation Category: laboratory analysis; Sampling Instrument: Technicon Auto Analyzer II; Sampling and Analyzing Method: Nutrient concentrations were determined using standard automated colorimetric techniques (APHA, 1990) on a Technicon Auto Analyzer II, as detailed in Davis and Simmons (1979). Nitrate+Nitrite was filtered through a pre-rinsed 0.2-µm HA Millipore filter or a 0.2-µm Nucleopore filter and analyzed using the cadmium reduction method. The detection limit for this method is 0.01 mg N/L.; Data Quality Method: expert review.
- Parameter or Variable: particulate silica (measured); Units: milligrams per liter; Observation Category: laboratory analysis; Sampling Instrument: Technicon Auto Analyzer II; Sampling and Analyzing Method: Nutrient concentrations were determined using standard automated colorimetric techniques (APHA, 1990) on a Technicon Auto Analyzer II, as detailed in Davis and Simmons (1979). Particulate silica (PSI) was determined on 100 mL aliquots of water filtered through a 0.45-mm Nucleopore filter and then extracted with 0.2N NaOH at 95•C for 30 minutes (Krausse et al., 1983). The extract was neutralized with 1N H2SO4 and silica (SiO2) concentrations were determined by the heteropoly blue method.; Data Quality Method: expert review.
- Parameter or Variable: dissolved silica (measured); Units: mil; Observation Category: laboratory analysis; Sampling Instrument: Technicon Auto Analyzer II; Sampling and Analyzing Method: Nutrient concentrations were determined using standard automated colorimetric techniques (APHA, 1990) on a Technicon Auto Analyzer II, as detailed in Davis and Simmons (1979). Dissolved silica was filtered through a pre-rinsed 0.2-µm HA Millipore filter or a 0.2-µm Nucleopore filter and analyzed using the heteropoly blue method.; Data Quality Method: expert review.
- Parameter or Variable: chloride (measured); Units: milligram; Observation Category: laboratory analysis; Sampling Instrument: Technicon Auto Analyzer II; Sampling and Analyzing Method: Nutrient concentrations were determined using standard automated colorimetric techniques (APHA, 1990) on a Technicon Auto Analyzer II, as detailed in Davis and Simmons (1979). Dissolved silica was filtered through a pre-rinsed 0.2-µm HA Millipore filter or a 0.2-µm Nucleopore filter and analyzed using the mercuric thiocyanide/ferric ammonium sulfate method.; Data Quality Method: expert review.
- Parameter or Variable: PARTICULATE ORGANIC CARBON (measured); Units: milligrams per liter; Observation Category: laboratory analysis; Sampling Instrument: Perkin Elmer (model 2400) CHN elemental analyzer; Sampling and Analyzing Method: Samples for particulate organic carbon were processed in triplicate by filtering 50 or 100 mL of sample through pre-combusted GFF filters. Filters were frozen until analysis, then thawed, acidified with 10% HCl, and dried. Measurements were made with a Perkin Elmer (model 2400) CHN elemental analyzer.; Data Quality Method: expert review.
- Parameter or Variable: DISSOLVED ORGANIC CARBON (measured); Units: milligrams per liter; Observation Category: laboratory analysis; Sampling Instrument: Shimadzu total organic carbon analyzer (model TOC-5000); Sampling and Analyzing Method: Samples for dissolved organic carbon were processed in triplicate by filtering 50 or 100 mL of sample through pre-combusted GFF filters. The filtrate was acidified with HCl and sparged with air for 6 minutes to remove CO2. DOC was determined using a Shimadzu total organic carbon analyzer (model TOC-5000) fitted with an auto sampler.; Data Quality Method: expert review.
- Parameter or Variable: Total Suspended Solids (TSS) (measured); Units: milligrams per liter; Observation Category: laboratory analysis; Sampling Instrument: filter; Sampling and Analyzing Method: "Total suspended solids were determined by filtering between 500 and 2,000 mL of sample through a pre-dried, pre-weighed Whatman GFC 47-mm filter. The filters were then dried at 60•C for at least 48 h and reweighed."; Data Quality Method: expert review.
- Parameter or Variable: total alkalinity (measured); Units: milligrams per liter; Observation Category: laboratory analysis; Sampling Instrument: pH meter; Sampling and Analyzing Method: Alkalinity was determined from the milk-equivalents of acid needed to bring the pH of the water sample below 4.0 (Davis and Simmons, 1979). Twenty mL of sample was pipetted with a volumetric buret into a chemically clean polyethylene bottle that contained 5 mL of 0.01 N HCL. Additional 1 mL aliquots of acid were added if the pH was above 4.0.; Data Quality Method: expert review.
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