Watershed Acidification — A Chromatographic Process
Drainage watersheds acidify from the top down. The acidification involves the stripping of base cations, Al, and Fe from various reservoirs. A front of acidification moves downstream from the head of the watershed. As base cations become depleted, they are removed from the watershed. Al and Fe, however, move progressively downstream, eluted by acid and precipitated in higher pH regions of the watershed. As they do, acid neutralizing capacity accumulates in streambeds. This capacity must be stripped by progressive acidification before the stream (and lower lakes) can become chronically acidic. The capacity of this mechanism may be sufficient to retard chronic acidification by years. The mechanism of translocation of Al and Fe and, to a lesser extent, base cations serves to damp episodic pH depressions in streams and extend the recovery from periods of low pH.
KeywordsBase Cation Acidic Precipitation Acid Neutralize Capacity Chemical Weathering Alkalinity Production
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- Henriksen, A., Skogheim, O. K., and Rosseland, B. O.: 1984, Vatten. 40, 255Google Scholar
- Hultberg, H.: 1985, Ecol. Bull. 37, 133Google Scholar
- Leivestad, H., Hendrey, G., Muniz, I. P. and Snekvik, E.: 1976. ‘Effects of acid precipitation on freshwater organisms’, in F. H. Braekke (ed.), Impact of Acid Precipitation on Forest and Freshwater Ecosystems in Norway, The SNSF Project, Oslo, Norway, pp 86–111Google Scholar
- Matschullat, J., Heinrichs, H., and Schneider, J.: in review, Heavy Metals and Water Acidification - Sources and behavior of pollutants in sediments of a drinking water reservoir (Western Harz Mountains, F.R.G.): Sc. of the Total Environ.Google Scholar
- Miotke, F. D.: 1974, Abh. Korst-n. Hohlenkunde, Reihe A., Heftq, 9, 1Google Scholar
- Norton, S. A. and Henriksen A.: 1983, Vatten. 39, 346Google Scholar
- Norton, S. A., Henriksen, A., Wathne. B. M., and Veidel, A.: 1987, Aluminum dynamics in response to experimental additions of acid to a small Norwegian stream, in Proceedings of an international symposium on Acidification and water pathways, The Norwegian National Committee for Hydrology in cooperation with Unesco and WMO, the National Committees of Danmark, Finland and Sweden, VOL I, pp 249–257Google Scholar
- Norton, S. A., Kahl, J. S., and Davis, R. B.: 1988b, Paleolimnological evidence for terrestrial mobilization of iron by acidic precipitation (abs.): Trace Metals in Lakes, Internat. Conf., Burlington, Ontario.Google Scholar
- Norton, S. A., Kahl, J. S., Henriksen, A., and Wright, R. F.: in press, ‘Buffering of pH by sediments in streams and lakes’ in Advances in Environ. Sci., Acid. Precip.,3, Springer-VerlagGoogle Scholar
- Rudd, J. W. M. (ed.): 1987, Acidification of the Moose River System in the Adirondack Mountains of New York State, Biogeochemistry, 3, 296 pGoogle Scholar
- Vesely, J., Sulcek, Z. and Majer, V.: 1985, Geol. Survey (Prague) J. 60, 9Google Scholar