The Differentiation between Point and Diffuse Industrial Pollution of the Floodplain of the Ploučnice River, Czech Republic

• Published in: Water, air, and soil pollution air, and soil pollution, 2013-09, Vol.224 (9), p.1, Article 1688
• Main Authors: Majerová, L., Matys Grygar, T., Elznicová, J., Strnad, L.
• Format: Article
• Language: English
• Subjects: Alluvium; Animal, plant and microbial ecology; Anthropogenic factors; Applied ecology; Archives & records; Atmospheric Protection/Air Quality Control/Air Pollution; Biological and medical sciences; Cenozoic; Climate Change/Climate Change Impacts; Contaminated sediments; Copper; Cretaceous; Earth and Environmental Science; Environment; Environmental monitoring; Floodplains; Fundamental and applied biological sciences. Psychology; Geochemistry; Heavy metals; Hydrogeology; Industrial pollution; Leaching; Lead; Marine sediments; Mining; Pollutants; Pollution; Rivers; Sediments; Soil Science & Conservation; Statistical analysis; Water pollution; Water Quality/Water Pollution; Watersheds
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-013-1688-9

Pollution by heavy metals (Co, Cu, Ni, Pb, Sb and Zn), 226 Ra and U was studied in eight profiles (1.0–1.8 m deep) in the floodplain sediments of the Ploučnice River, the Czech Republic. The element concentrations were processed by establishing local geochemical background functions from non-polluted overbank fines yet not affected by reductimorphic processes and a subsequent calculation of enrichment factors in the polluted strata. In the case of Cu and Ni, the geogenic variability of the watershed (Cretaceous marine sediments and Cenozoic volcanics and their weathering products) was successfully handled using different background functions in two parts of the studied area, which allowed us to decipher the anthropogenic and natural portions of the heavy metals and hence evaluate the history of pollution. The upper course of the river drains an extensive area of so-called chemical mining (underground acid leaching of low-grade U-bearing sediments) and hydrometallurgical processing in Stráž pod Ralskem that started in the late 1960s and operated without waste-processing plants up to 1989. The river system has consequently been impacted by U and gamma-emitting 226 Ra and obviously also by divalent heavy metals (Co, Ni, Zn). In the entire study area, that pollution was preceded by increasing levels of Cu, Pb and Sb and by the 206 Pb/ 207 Pb ratio decreasing from 1.20 towards 1.17, which had started earlier in the twentieth century before the U mining. That pre-mining pollution can be attributed to diffuse anthropogenic activities of regional or continental importance. The most recent 206 Pb/ 207 Pb ratio in the Ploučnice alluvium coincides with that of peatbog profiles on the borders of the Czech Republic, showing the usefulness of floodplains as pollution archives of widespread regional to continental pollution signals.