Soil respiration, ATP content, and Photobacterium toxicity test as indicators of metal pollution in soil

The effects of heavy metal deposition from four different metalworks on soil respiration, ATP content, and toxicity to Photobacterium phosphoreum were examined. Soil samples were collected along a transect through the pollution gradients. Vegetation and soil types were homogeneous throughout the transects. Soil respiration was measured as CO2 production in closed bottles using an IR-gas analyzer. The ATP content was measured with a bioluminometric assay after trichloracetic acid extraction of soil. The toxicities of distilled water extracts of soil samples were evaluated by the standard P. phosphoreum toxicity test and the metal content of these water extracts was measured as the bioavailable fraction of the heavy metal pollution in the soil. Soil respiration and ATP content were strongly affected by the heavy metal content in the soil. The correlation between the methods was high. The P. phosphoreum procedure can be used to estimate the toxicity of soils heavily polluted by metals. However, soil respiration and ATP content appear to be more sensitive indicators of soil pollution. © 1994 by John Wiley & Sons, Inc..