Pollutant aquatic systems

FIGURE 10. Gas chromatogram of hydrocarbons obtained from the plant sample from aquatic system polluted with oily products. 

The fate of a pollutant in an aquatic system may be expressed as follows ... 

Counterexamples teach a lesson that these exaggerations of aquatic biological activity are highly idiosyncratic and depend on the fluxes of nutrients, the types of phytoplankton ecosystems that are involved, and - most importantly - the local and regional circulations of the aquatic system. For example, the Mediterranean Sea is landlocked and has many large pollution sources, but the large flux of nutrient-poor ("impoverished") water from the Atlantic... 

Kelly CA, Rudd JWM, St. Louis VL, Heyes A. 1995. Is total mercury concentration a good predictor of methylmercury concentration in aquatic systems Water Air Soil Pollut 80 715-724. 

Baughman, G.L., Paris, D.F. (1981) Microbial bioconcentration of organic pollutants from aquatic systems-a critical review. CRC Critical Reviews in Microbiology, pp. 205-228. 

Dzombak, D. A. and F. M. M. Morel, 1987, Adsorption of inorganic pollutants in aquatic systems. Journal of Hydraulic Engineering 113,430-475. 

Allard, B. and I. Arsenie. 1991. Abiotic reduction of mercury by humic substances in aquatic system — an important process for the mercury cycle. Water Air Soil Pollut. 56 457-464. 

Karickhoff SW (1984) Organic pollutant sorption in aquatic systems. J Hydraul Eng 110 707-735... 

The adsorption of ions on iron oxides regulates the mobility of species in various parts of the ecosystem (biota, soils, rivers, lakes, oceans) and thereby their transport betv een these parts. Examples are the uptake of plant nutrients from soil and the movement of pesticides and other pollutants from soils into aquatic systems. In such environments various ions often compete with each other for adsorption sites. Adsorption is the essential precursor of metal substitution (see Chap. 3), dissolution reactions (see Chap. 12) and many interconversions (see Chap. 14). It also has a role in the synthesis of iron oxides and in crystal growth. In industry, adsorption on iron oxides is of relevance to flotation processes, water pollution control and waste and anticorrosion treatments. 

Cairns has spent virtually his entire life studying and writing about the way in which ecosystems respond to stresses, especially those caused by human activities. He has focused his work on the way in which industrial wastes, pesticides, and other pollutants have damaged rivers, streams, lakes, and other aquatic systems and on the ways in which those systems can be restored to natural, nonpolluted, healthy conditions. 

The problem of toxic pollutants is difficult to handle because of the great variety of chemicals involved. They represent a hazard not only to aquatic life, but also to human health, either through direct exposure or indirectly through consumption of contaminated fish or waterfowl. The degree of hazard depends on the pollutanf s toxicity, rate of discharge, persistence and distribution in the aquatic system, and bioaccumulation potential. Some highly volatile compounds, when discharged into water, evaporate and become air pollutants. 

In this section we will develop the mathematical tools to describe mass transfer at diffusive boundaries. Again, it is our intention to demonstrate that diffusive boundaries have common properties, although the physics controlling them may be different. We will then apply the mathematical tools to the process of dilution of a pollutant cloud in an aquatic system (ocean, lake, river). Here the boundary is produced by the localized (continuous or event-like) input of a chemical that first leads to a confined concentration patch. The patch is then mixed into its environment by diffusion or dispersion. Note that in this case the physical characteristics on both sides of the... 

Eutrophication. Thus far N has been discussed in terms of its prominence as an acidic anion (i.e., as N03 ). As in terrestrial ecosystems, inorganic forms of N also act as nutrients in aquatic systems, and a possible consequence of chronic N loss from watersheds is the fertilization of lakes and streams. Establishing a link between N deposition and the eutrophication of aquatic systems depends on a determination that the productivity of the system is limited by N availability and that N deposition is a major source of N to the system. In many cases the supply of N from deposition is minor when compared to other anthropogenic sources, such as pollution from either point or nonpoint sources. 

Voice, T.C., C.P. Rice, and W.J. Weber Jr. 1983. Effect of solids concentration on the sorptive partitioning of hydrophobic pollutants in aquatic systems. Environ. Sci. Technol. 17(9) 513-518. 

Karickhoff, S.W. 1984. Organic Pollutant Sorption in Aquatic Systems. ]. Hydraulic Eng. ASCE 110, 707-735. 

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