Metal contamination of river floodplain soils
The Tisza River has great ecological and economic importance in central Europe. Its floodplain, an important part of the Hungarian Great Plain, is among the most biologically diverse areas in Europe, and the river provides drinking water and, irrigation, and supports an economy based on agriculture, fishing and tourism. In early 2000, accidental releases of massive mining effluents/sludge enriched in cyanide and metals (Cu, Pb and Zn primarily) from upstream areas into the Tisza tributaries occurred. Subsequent major floods mobilized and dispersed the mine effluents/sludge downstream and onto the floodplain, leading to a declared state of national emergency. Flood dispersal of heavy metal-lacten mud/sediments led to severe environmental impacts in planktonand macroinvertehrate communities. Data from surface and soil profile samples collected shortly after the floodings and subsequent samplings in 2001, 2002 and 2003 in the floodplain along the Tisza River indicate substantial enrichment of metals in the soil pedons. of the trace metals analyzed (Cd, Co, Cr, Pb, Cu, Mn, Ni and Zn), Cd and Zn are particularly concerning as their bioavailable (NH<,4> OAc-EDTA extractable) fraction, in most sites, exceeded the allowable threshold values (0. 50 mg/kg for Cd and 40 mg/kg for Zn) established by Hungary and WHO/FAO. These threshold values signal potential phytoaccumulation of metals for sensitive crops and the need for sensible management strategy. The results indicate that metal accumulation occurred primarily in surface softs, the bioavailable (extractable) fraction constituted a substantial portion of the total metal content, and that S was dominated by its soluble sulfate form The alkaline, calcareous nature of the soils in the profile partially allays concerns from transfer of the metals into the food chain and groundwater contamination. However, farmlands should not be cultivated to produce Cd-accumulating crops such as members of the lettuce family.
floodplain soil contamination heavy metals soil profile
Dorny C. Aclriano Zoltan Gyori Jozsef Prokisch Tanafis Nometh Steve Harper Larry T. West
University of Georgia, Savannah River Ecology Laboratory, P O Drawer E, Aiken, SC 29802, (803) 725-5 Debrecen University, Department of Food Science and Quality Control, 4032 Debrecen, Hungary Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences, University of Georgia, Department of Crop and Soil Sciences, Athens, GA 30602
国际会议
第九届痕量元素生物地球化学国际会议(9th International Conference on the Biogeochemistry of Trace Elements)
北京
英文
574-575
2007-07-15（万方平台首次上网日期，不代表论文的发表时间）