Coupling geochemical, mineralogical and microbiological approaches to assess the health of contaminated soil around the Almalyk mining and smelter complex, Uzbekistan.
This study describes the impact of airborne pollution resulting from mining and smelting activities on the soils of the Almalyk mining and industrial area (NE Uzbekistan). Samples were collected along a transect downwind of the industrial area. Enriched contents of some metals were found in the upper soil layers near the metallurgical complex (Zn≤3010 mg kg(-1), Pb≤630 mg kg(-1), Cd≤30 mg kg(-1)) which suggests that these metals were derived from local stack emissions. The morphology and internal microstructure of metal-bearing spherical particles found in the heavy mineral fraction suggest that these particles were probably a result of inefficient flue gas cleaning technique of the smelter. The highest metal concentrations were found also in soil solutions and exchangeable solid fractions from the first three locations, and decreased with increasing distance from the pollution source along transect. Thermodynamic equilibrium calculations suggest that the mobile metal pool in the contaminated soil is mainly controlled by dissolution of metal carbonates formed as weathering product of the metalliferous particles. The health of the microbiological soil ecosystem was assessed by measurements of basal respiration, nematode abundance, biomass-related C and N content, and microbial metabolic quotient qCO2. Significant correlations were found between the dissolved metal content and the microbiological health parameters, a negative one for Cmic/Corg ratio, and a positive one for qCO2. A negative correlation was found between the amount of nematodes and the metal contents suggesting that the contaminated soil has significant impact on the functioning of the microbiological community. A better understanding of the spatial variations in the whole ecosystem functioning due to airborne impact could be very useful for establishing suitable land use and best management practices for the polluted areas.
Geosciences Institute, Johannes Gutenberg University, Mainz 55099, Germany.
Nosir
N
Shukurov
Geosciences Institute, Johannes Gutenberg University, Mainz 55099, Germany.
Obidjon
O
Kodirov
Geosciences Institute, Johannes Gutenberg University, Mainz 55099, Germany.
Mirko
M
Peitzsch
Geosciences Institute, Johannes Gutenberg University, Mainz 55099, Germany. Electronic address: kersten@uni-mainz.de.
Michael
M
Kersten
The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel.
Stanislav
S
Pen-Mouratov
The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel.
Yosef
Y
Steinberger
D000818:Animals; D044822:Biodiversity; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D004787:Environmental Pollution / Q000706:statistics & numerical data; D007221:Industry; D008669:Metallurgy; D019216:Metals, Heavy / Q000032:analysis; D008906:Mining; D009348:Nematoda; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*; D014610:Uzbekistan
D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants
Bioindicator; Metabolic quotient; Metals; Microbial biomass; Nematodes; Smelter impact; Soil pollution