Sea and estuary water

Studies on electrophoretic mobility have provided additional data on the excess of charge at the interface between suspended matter and electrolytic medium. Particles in suspension in fresh, sea and estuarie waters appear ubiquitously to exhibit a small range of negative surface charge. This uniformity is attributed to the presence of organic surface coatings on the particles. 

Sediment and sludge Sludge and soil Sea and estuary water... 

The ion proportions in most river water is significantly different from that in seawater. As a result, river runoff can have a local impact on the ion ratios of coastal waters. This effect is most pronounced in marginal seas and estuaries where mixing with the open ocean is restricted and river input is relatively large. The variable composition of river water and its impact on the chemical composition of seawater are discussed further in Chapter 21. 

Sources include surface waters, wells, seas and estuaries, and recovered condensate. Many plants serve all their needs with municipal water, treated to potable quality, which may be based on surface water or well water. Public water supplies usually carry a firaction of a ppm of chlorine. When used as the principal supply to a plant, these must be dechlorinated before most direct uses in the process. 

With the possible exception of systems using sea water, estuarial waters, and/or industrially contaminated waters for cooling, condi-... 

Johnson and Pilson [229] have described a spectrophotometric molybdenum blue method for the determination of phosphate, arsenate, and arsenite in estuary water and sea water. A reducing reagent is used to lower the oxidation state of any arsenic present to +3, which eliminates any absorbance caused by molybdoarsenate, since arsenite will not form the molybdenum complex. This results in an absorbance value for phosphate only. 

Willie et al. [17] used the hydride generation graphite furnace atomic absorption spectrometry technique to determine selenium in saline estuary waters and sea waters. A Pyrex cell was used to generate selenium hydride which was carried to a quartz tube and then a preheated furnace operated at 400 °C. Pyrolytic graphite tubes were used. Selenium could be determined down to 20 ng/1. No interference was found due to, iron copper, nickel, or arsenic. 

Batley [28] examined the techniques available for the in situ electrodeposition of lead and cadmium in estuary water. These included anodic stripping voltammetry at a glass carbon thin film electrode and the hanging drop mercury electrode in the presence of oxygen and in situ electrodeposition on mercury coated graphite tubes. Batley [28] found that in situ deposition of lead and cadmium on a mercury coated tube was the more versatile technique. The mercury film, deposited in the laboratory, is stable on the dried tubes which are used later for field electrodeposition. The deposited metals were then determined by electrothermal atomic absorption spectrometry, Hasle and Abdullah [29] used differential pulse anodic stripping voltammetry in speciation studies on dissolved copper, lead, and cadmium in coastal sea water. 

Leah, R.T., S.J. Evans, and M.S. Johnson. 1992. Mercury in flounder (Platichthys flesus L.) from estuaries and coastal waters of the north-east Irish Sea. Environ, Pollut. 75 317-322. 

In a later study by the same group, the carboxylated metabolites were also included in the analysis [4]. This time, water samples were taken in the Venice lagoon as well as in the Adriatic Sea and in a river reaching the estuary. 

Alkylphenol derivatives in the North Sea and UK coastal waters Blackburn and Waldock [11] undertook a survey of water concentrations of alkylphenols (APs) in rivers and estuaries in England and Wales. Locations were selected to represent a wide range of possible AP inputs, from both agricultural and industrial sources. For all samples, both filtered and unfiltered water were treated, to determine both the dissolved and the total extractable APs by GC-MS. 

Kinetics of Reactions in Natural Waters. In considering equilibria and kinetics in natural water systems, it is usually necessary to recall that widely different time scales need to be identified with chemical reactions in different systems. Relatively short times (days to weeks) are available for approach to equilibrium in rivers, smaller lakes, reservoirs, and estuaries. Times for reaction in large lakes, seas, and perhaps typical ground waters are of the order of tens to hundreds of years. In ocean waters, the reaction time may range from thousands of years to... 

The mixture of organic constituents in the marine environment is extremely complex. Their origin is partly terrigenuous many compounds are produced in the marine environment itself. The different sources and their relative importance for the complexation of trace metals in estuaries, coastal seas and open ocean are riverine input, runoff from the coastal zone, resuspension, import of water mases, atmospheric input and in situ biological production. 

The AYRSSM allows us to estimate the dependence of pollution level in the AYRS estuary as a function of anthropogenic activity. Suppose that the intensity of sources of heavy metals is such that their concentration in the water near Angarsk, Irkutsk, Krasnoyarsk, Bratsk, and Ust-Ilimsk can be described by a stationary function, supporting heavy metal concentrations at level h at each of these cities. Computer experiments show that there is a stable correlation between h, the heavy metal concentration in the AYRS estuary, and the water flow rate fi. An increase in h of 10% leads to a rise of pollution input to the Kara Sea by 2.5%. An increase in h of 1% leads to a rise of pollution input to the Kara Sea by 0.7%. These results are correct only when variances in values fi and h are close to their average estimates. Near their critical values the estimates are unstable and more detailed models are required. 

Significant amounts of OCPs were found in water of rivers, estuaries and seas, and generally, sewage water concentrations > river concentrations > estuary concentrations > sea concentrations. Levels of OCPs in sewage from Guangzhou had the highest concentrations of DDTs and HCHs... 

Bowles and Apte [698] have described a method for the determination of methylmercuiy compounds in non saline waters using steam distillation followed by gas chromatography with an atomic fluorescence spectrometric detector. These workers evaluated steam distillation as a technique for the separation of methylmercury compounds from water and obtained recoveries in spiking experiments ranging from approximately 100% in fresh waters and estuaries to 80% in sea water. 

One can infer that, during the period from the middle of the Middle Pleistocene to the second half of the Late Pleistocene, the area of the Black Sea was occupied by a brackish-water sea basin inhabited by euryhaline and stenohaline Mediterranean fauna. At the maximum of its development, its salinity was almost twice as great as the salinity of the present-day sea and its level seems to have reached absolute marks of + 6-8 m sea bays and estuaries deeply penetrated into the land over coastal depressions. With respect to selected characteristics, this basin strongly differed from the preceding (Chaudian) and the subsequent (New Euxinian) basins. First of all, this refers to the large-scale one-way connection with the Mediterranean Sea, which defined the relatively high salinity of the basin and the character of its dwellers. 

Sometimes semi-enclosed coastal water bodies are situated between a mouth reach of the river and open nearshore zone [20]. These intermediate parts of the river mouth areas can be presented as narrow sea bays, lagoons, limans, and estuaries. These coastal water bodies are often separated from the open nearshore by coastal bars, spits, barrier islands, etc. and connected with it through relatively narrow outlets. These semi-enclosed coastal water bodies are characterized by active interaction and mixing of river and seawater. 

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