Note: Intro -- Methods of Seawater Analysis -- Contents -- List of contributors -- 1 Sampling -- 1.1 Introduction -- 1.2 Sampling strategy -- 1.3 Sampling techniques -- 1.3.1 Surface water sampling -- 1.3.2 Water samplers for major hydrochemical variables -- 1.3.3 Water samplers for trace constituents -- 1.3.3.1 Trace elements -- 1.3.3.2 Trace organic compounds -- 1.3.4 Specific samplers -- 1.3.5 Collection of marine particles -- 1.3.5.1 Collection of suspended particulate matter (SPM) -- 1.3.5.2 Collection of sinking particulates -- 1.4 Sampling errors -- 1.5 Quality control -- 1.5.1 Precision -- 1.5.2 Accuracy -- 1.5.3 Limit of detection -- References to Chapter 1 -- 2 Filtration and storage -- 2.1 Filtration -- 2.1.1 General remarks -- 2.1.2 Filters -- 2.1.3 Filtration techniques -- 2.1.3.1 Vacuum filtration -- 2.1.3.2 Pressure filtration -- 2.1.3.3 In situ filtration -- 2.1.3.4 Centrifugation -- 2.2 Storage -- 2.2.1 General remarks -- 2.2.2 Storage for the determination of major compounds -- 2.2.3 Storage for the determination of nutrients -- 2.2.3.1 General remarks -- 2.2.3.2 Refrigeration -- 2.2.3.3 Poisoning -- 2.2.4 Storage for the determination of trace elements -- References to Chapter 2 -- 3 Determination of salinity -- 3.1 Introduction -- 3.2 Symbols and abbreviations -- 3.3 Definition of salinity -- 3.3.1 Early concepts -- 3.3.2 The practical salinity scale of 1978 (PSS78) -- 3.4 Measurement of the conductivity ratio -- 3.5 Salinity from bench salinometers -- 3.5.1 Purpose -- 3.5.2 Standard seawater -- 3.5.3 Sampling -- 3.5.4 The Guildline AUTOSAL Model 8400 B -- 3.5.5 The Beckman Model RS1O -- 3.5.6 Data logging -- 3.5.7 Substandards -- 3.6 Salinity from in situ measurements: CTD profilers -- 3.6.1 Principles -- 3.6.2 Operation of CTD-rosette sampler systems -- 3.6.3 Calibration -- 3.6.4 Data processing -- References to Chapter 3. , 4 Determination of oxygen -- 4.1 Introduction -- 4.2 Principle of the determination -- 4.3 Error sources and interferences -- 4.4 Reagents -- 4.5 Instruments -- 4.6 Procedure -- 4.6.1 Standardization of the thiosulphate solution -- 4.6.2 Subsampling and fixation of dissolved oxygen -- 4.6.3 Storage -- 4.6.4 Titration -- 4.6.5 Determination of the reagent blank -- 4.6.6 Calculation of the result -- 4.6.7 Accuracy and precision -- References to Chapter 4 -- 5 Determination of hydrogen sulphide -- 5.1 Introduction -- 5.2 Units -- 5.3 Analytical methods -- 5.3.1 Method by Fonselius -- 5.3.1.1 Reagents -- 5.3.1.2 Special apparatus -- 5.3.1.3 Sampling -- 5.3.1.4 Preservation of samples -- 5.3.1.5 Procedure -- 5.3.1.6 Analysis -- 5.3.1.7 Dilution of samples -- 5.3.1.8 Standardization of the method -- 5.3.1.9 Calibration of the method -- 5.3.2 Method by Cline -- 5.3.2.1 Reagents -- 5.3.2.2 Special apparatus -- 5.3.2.3 Sampling -- 5.3.2.4 Procedure -- 5.3.2.5 Analysis -- 5.3.2.6 Standardization and calibration of the method -- 5.3.3 Titration methods -- 5.3.4 Methods using mercury compounds -- References to Chapter 5 -- 6 Determination of thiosulphate and sulphur -- 6.1 Introduction -- 6.2 Principle of the determination of thiosulphate -- 6.2.1 Apparatus -- 6.2.2 Reagents -- 6.2.3 Sampling and storage -- 6.2.4 Procedure -- 6.2.4.1 Standardization of the thiosulphate solution -- 6.2.4.2 Titration of the sample -- 6.2.5 Calculation of the thiosulphate content of the sample -- 6.2.6 Interferences -- 6.3 Principle of the determination of sulphur -- 6.3.1 Apparatus -- 6.3.2 Reagents -- 6.3.3 Sampling and storage -- 6.3.4 Procedure -- 6.3.5 Calculations -- 6.3.6 Interferences -- 6.4 Other methods -- References to Chapter 6 -- 7 Determination of pH -- 7.1 Introduction -- 7.2 List of symbols -- 7.3 Definition of pH -- 7.4 pH scales in seawater. , 7.5 Measurement of pH -- 7.5.1 Potentiometry -- 7.5.1.1 Theory -- 7.5.1.2 Tris buffers -- 7.5.1.3 Practical considerations -- 7.5.2 Spectrophotometry -- 7.5.2.1 Theory -- 7.5.2.2 Indicator pK values for seawater -- 7.5.2.3 Measurement procedures -- 7.5.3 Comparison of the various techniques -- 7.5.4 Correction of pH to in situ conditions -- 7.5.4.1 Empirical equations for correction to in situ temperature -- 7.5.4.2 Empirical equations for correction to in situ pressure -- References to Chapter 7 -- 8 Determination of total alkalinity and total dissolved inorganic carbon -- 8.1 Introduction -- 8.2 List of symbols -- 8.3 Sampling and reference materials -- 8.3.1 Sampling -- 8.3.2 Standard reference materials -- 8.4 Total alkalinity -- 8.4.1 Definition -- 8.4.2 Potentiometric titrations -- 8.4.2.1 Instrumentation -- 8.4.2.2 Analytical procedure -- 8.4.2.3 Evaluation procedures -- 8.4.3 Back titration method -- 8.4.3.1 Reagents -- 8.4.3.2 Analytical procedure -- 8.4.3.3 Calculation of results -- 8.4.3.4 Precision and accuracy -- 8.5 Total dissolved inorganic carbon -- 8.5.1 Potentiometric titrations -- 8.5.2 Coulometric determination technique -- 8.5.2.1 Instrumentation -- 8.5.2.2 Analytical procedure -- 8.5.2.3 Calculation and expression of results -- 8.6 Thermodynamic calculations of the C02 system in seawater -- 8.6.1 Equations describing the C02 system in seawater -- 8.6.2 Selection of stability constants -- 8.6.3 Calculations with two measured C02 parameters -- 8.6.3.1 Calculations with pH and AT measured -- 8.6.3.2 Calculations with pH and f(C02) measured -- 8.6.3.3 Calculations with pH and CT measured -- 8.6.3.4 Calculations with AT and CT measured -- 8.6.3.5 Calculations with AT and f(C02) measured -- 8.6.3.6 Calculations with CT and f(C02) measured -- 8.6.4 Errors arising from the calculations -- References to Chapter 8 -- Appendix 8A. , 9 Determination of carbon dioxide partial pressure (p(CO2)) -- 9.1 Introduction -- 9.2 Principle of the measurement -- 9.3 Apparatus for continuous mode of operation -- 9.3.1 The equilibrator -- 9.3.2 The analytical system -- 9.4 Reagents -- 9.4.1 Calibration gases -- 9.4.2 Gas purification reagents -- 9.5 Calculation of results -- 9.6 Accuracy -- References to Chapter 9 -- 10 Determination of nutrients -- 10.1 Introduction -- 10.1.1 Oceanic distributions of nutrients -- 10.1.2 Chemistry of nutrients in the marine environment -- 10.2 Analytical methods -- 10.2.1 Pretreatment of samples -- 10.2.2 The matrix -- 10.2.3 References and standard materials -- 10.2.4 Calibration, blank determination and calculation procedures -- 10.2.5 Determination of dissolved inorganic phosphate -- 10.2.5.1 Principle of the method -- 10.2.5.2 Range and precision -- 10.2.5.3 Interferences -- 10.2.5.4 Reagents -- 10.2.5.5 Analytical procedures -- 10.2.6 Determination of dissolved inorganic phosphate in the presence of arsenic -- 10.2.6.1 Principle of the method -- 10.2.6.2 Reagents -- 10.2.6.3 Analytical procedures -- 10.2.7 Determination of dissolved inorganic phosphate by an extraction procedure (high-sensitivity method) -- 10.2.7.1 Principle of the method -- 10.2.7.2 Range and precision -- 10.2.7.3 Interferences -- 10.2.7.4 Reagents -- 10.2.7.5 Analytical procedure -- 10.2.8 Determination of nitrite -- 10.2.8.1 Principle of the method -- 10.2.8.2 Range and precision -- 10.2.8.3 Interferences -- 10.2.8.4 Reagents -- 10.2.8.5 Analytical procedures -- 10.2.9 Determination of nitrate -- 10.2.9.1 Principle of the method -- 10.2.9.2 Range and precision -- 10.2.9.3 Interferences -- 10.2.9.4 Reagents -- 10.2.9.5 Preparation of the reductor -- 10.2.9.6 Analytical procedures -- 10.2.10 Determination of ammonia -- 10.2.10.1 Principle of the method -- 10.2.10.2 Range and precision. , 10.2.10.3 Interferences -- 10.2.10.4 Reagents -- 10.2.10.5 Analytical procedures -- 10.2.1 1 Determination of dissolved inorganic silicate -- 10.2.11.1 Principle of the method -- 10.2.11.2 Range and precision -- 10.2.11.3 Interferences -- 10.2.11.4 Reagents -- 10.2.11.5 Analytical procedures -- 10.2.12 Determination of nitrogen, phosphorus and silicon in particulate and dissolved organic matter -- 10.2.12.1 Equipment -- 10.2.12.2 Calibration and calculation of total and organic nutrients -- 10.2.13 Determination of total and organic phosphorus by acid persulphate oxidation -- 10.2.13.1 Reagents -- 10.2.13.2 Analytical procedure -- 10.2.14 Determination of total and organic phosphorus by alkaline persulphate oxidation -- 10.2.14.1 Reagents -- 10.2.14.2 Analytical procedure -- 10.2.14.3 Dilution factors (see Section 10.2.12.2) -- 10.2.15 Determination of polyphosphates -- 10.2.15.1 Analytical procedure -- 10.2.16 Determination of total and organic nitrogen after persulphate oxidation -- 10.2.16.1 Range and precision of the method -- 10.2.16.2 Reagents -- 10.2.16.3 Analytical procedure -- 10.2.17 Simultaneous oxidation of nitrogen and phosphorus compounds with persulphate -- 10.2.17.1 Range and precision of the method -- 10.2.17.2 Oxidizing reagent -- 10.2.17.3 Analytical procedure -- 10.2.18 Determination of total silicon -- 10.2.18.1 Principle of the method -- 10.2.18.2 Reagents -- 10.2.18.3 Analytical procedure -- 10.2.19 Determination of total silicon by carbonate fusion -- 10.2.19.1 Reagents -- 10.2.19.2 Analytical procedure -- 10.3 Automated nutrient analysis -- 10.3.1 Principle of automated analysis -- 10.3.2 The sampler -- 10.3.3 The proportioning pump -- 10.3.4 The analytical manifold -- 10.3.4.1 Standard manifold components -- 10.3.4.2 Heating and cooling -- 10.3.4.3 Special devices -- 10.3.4.4 The flow-through spectrophotometer. , 10.3.5 Data acquisition.