Influence of heavy metal pollution on some soil-biological parameters in the alluvium of the Litavka river

Soil characteristics may be negatively influenced by the pollution. The soi ls most polluted by hazardous elements are probably alluvial soils. One of them is the alluvium of the Litavka river. The heavy metal content was much higher in some cases than the treshold values, allowed by the Czech standa rds. There was a decreased metal content found in general, along the river and with the distance from the pollution source. Metal content in the plant s was reflected somehow the soil pollution level of the selected sites. Val ues of the heavy metal concentrations in the shoots were generally signific antly lower than those in the roots for all investigated metals in this stu dy. The effect of soil contamination on the soil microbial parameters is pr esented. An especially high number of the total countable bacteria was foun d at the lowest polluted sites. Their amount also decreased with distance o f pollution site (with the increasing concentrations of pollutants). Number of the spore-forming bacteria and oligotrophic bacteria has shown the same tendency. The results of the enzyme activity are presented. The lowest act ivity of dehydrogenases was found at sites where the concentration of pollu tants was found to be the highest. Significant inhibition of amylase activi ty was observed only at the highest soil contamination level. Among the soi l enzymes investigated, the invertase activity proved to be the most sensit ive indicator of the soil pollution. The highest activity was found at site s, which are representing a relatively clean (unpolluted) area. The colonis ation rates of the representing grass types by the arbuscular my corrhizal fungi are shown.