Surface waters, nature

Emerson, S., Quay, P., Karl, D. et al. (1997). Experimental determination of the organic carbon flux from open-ocean surface waters. Nature 389, 951-954. 

Carbon enters the atmosphere mainly as the result of respiration and burning of any kind. The oceans provide a slower, smaller pathway for carbon to enter the atmosphere. Dissolved carbon dioxide moves through the oceans waters in currents. At some places on the planet, mainly near the equator, currents bring cold water rich in carbon dioxide from deep in the ocean to the sea surface, where the Sun warms it. These warm surface waters naturally release carbon dioxide into the atmosphere. 

Schmitt-Kopplin, P., Freitag, D., Kettrup, A., Schoen, U., and Egeberg, P. (1999a). Capillary zone electrophoretic studies on Norwegian surface water natural organic matter. Environ. Int. 25, 259-274. 

Dore, J. E., Popp, B. N., Karl, D. M., and Sansone, P. J. (1998). A large source of atmospheric nitrous oxide from subtropical North Pacific surface waters. Nature 396, 63—66. 

Maurice P. A., Pullin M. J., Cabaniss S. E., Zhou Q., Namjesnik-Dejanovic K., and Aiken G. R. (2002) A comparison of surface water natural organic matter in raw filtered water samples, XAD, and reverse osmosis isolates. Water Res. 36, 2357-2371. 

Sullivan T. J., Driscoll C. T., Gherini S. A., Munson R. K., Cook R. B., Charles D. F., and Yatsko C. P. (1989) Influence of aqueous aluminum and organic acids on measurement of acid neutralizing capacity in surface waters. Nature 338, 408-410. 

Ferek, R. J., and Andreae, M. O. (1994) Photochemical Production of Carbonylsulfide in Marine Surface Waters, Nature 307, 148-150. 

Figure 11 Depth profiles of (a) N2O concentration and (b) and (c) <5 0 of N2O at station ALOHA in the subtropical North Pacific (22° 45 N, 158° W) during four separate cruises. The solid line in (a) indicates theoretical saturation with atmospheric N2O at in situ temperatures and salinities. The minima in and <5 0 around 200 m are thought to be due to significant in situ production of N2O from nitrification. The broad isotopic maxima at depth are likely due to N2O consumption, perhaps in the denitrifying waters along the eastern Pacific margin. The filled squares at the top of (b) and (c) represent measurements of <5 N and <5 0 of atmospheric N2O during the Hawaii Ocean Time-series 76 cruise, and arrows indicate the range of historical measurements as of the late 1980s. Reprinted from Dore JE, Popp BN, Karl DM, and Sansone FJ (1998) A large source of atmospheric nitrous oxide from subtropical North Pacific surface waters. Nature 396 63-66.

Most pollutants in natural waters are associated with natural organics. In surface waters, natural organics co-predptitate with calcium carbonate. Organics are also known to inhibit calcite precipitation (Steinberg and Muenster (1985)). In the following sections reported interactions between natural organics and cations, trace metals and other compounds such as pesticides are summarised. 

Surface Water Naturally available fresh water on the earth s surface in rivers, lakes or wetlands is called surface water. Natural replenishment of surface water takes place through precipitation. Surface water is depleted through natural processes like evaporation, discharge to seas and oceans and sub surface seepage. Human activities can have severe detrimental effects on the quality and availability of surface water. The upper limit of human consumption is restticted by the rate of precipitation within a watershed. Pulling in water from other watersheds through canals or pipelines can increase natural surface water in a particular watershed. Surface water is more prone to pollution from various human actions and needs extensive treatments to make it suitable for human consumption. 

Possible negative environmental effects of fertilizer use are the subject of iatensive evaluation and much discussion. The foUowiag negative effects of fertilizer usage have been variously suggested (113) a deterioration of food quaUty the destmction of natural soil fertility the promotion of gastroiatestiaal cancer the pollution of ground and surface water and contributions toward the destmction of the ozone layer ia the stratosphere. 

Water and Waste Water Treatment. PAG products are used in water treatment for removal of suspended soHds (turbidity) and other contaminants such as natural organic matter from surface waters. Microorganisms and colloidal particles of silt and clay are stabilized by surface electrostatic charges preventing the particles from coalescing. Historically, alum (aluminum sulfate hydrate) was used to neutralize these charges by surface adsorption of Al cations formed upon hydrolysis of the alum. Since 1983 PAG has been sold as an alum replacement in the treatment of natural water for U.S. municipal and industrial use. 

Surface-water hydrology The local surface-water hydrology of the area is important in estahhshing the existing natural drainage and runoff characteristics that must he considered. Other conditions of flooding must also he identified. 

For structures and equipment, the utility should be located where it cannot be affected by natural and climatic conditions. This includes (1) corrosive pollution that may be airborne, (2) prevalent winds, and (3) surface water currents from near or remote sources. 

Some petroleum geologists believe that there may be more methane trapped in hydrates than what is associated with natural gas reserves. However, as an energy source, there is considerable uncertainty whether this methane can ever be recovered safely, economically, and with minimal environmental impact. The Russians have experimented with the use of antifreeze to break down hydrates at some onshore locations in Siberia. But perhaps a more promising approach would be to pipe warm surface water to the bottom to melt the hydrates, with a collector positioned to convey the gas to the surface. Another approach might be to free methane by somehow reducing the pressure on the methane hydrates. 

Variability of Seawater Vertical sections through seawater showing the distribution of temperature, salinity, and oxygen for the Pacific Ocean and Western Atlantic Ocean are shown in Figures 21.3 and 21.4. The global variability of natural seawater and its effects on corrosion have been reviewed in particular with respect to seasonal variation of temperature, salinity, oxygen and pH in the Pacific surface water. Data is also given on... 

Table II summarizes analytical data for dissolved inorganic matter in a number of natural water sources (J3, 9, J 9, 20, 21). Because of the interaction of rainwater with soil and surface minerals, waters in lakes, rivers and shallow wells (<50m) are quite different and vary considerably from one location to another. Nevertheless, the table gives a useful picture of how the composition of natural water changes in the sequence rain ->- surface water deep bedrock water in a granitic environment. Changes with depth may be considerable as illustrated by the Stripa mine studies (22) and other recent surveys (23). Typical changes are an increase in pH and decrease in total carbonate (coupled), a decrease in 02 and Eh (coupled), and an increase in dissolved inorganic constituents. The total salt concentration can vary by a factor of 10-100 with depth in the same borehole as a consequence of the presence of strata with relict sea water. Pockets with such water seem to be common in Scandinavian granite at >100 m depth.

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